DICHLORVOS
CASRN: 62-73-7
For other data, click on the Table of Contents

Human Health Effects:

Evidence for Carcinogenicity:

Evaluation: There is inadequate evidence in humans for the carcinogenicity of dichlorvos. There is sufficient evidence in experimental animals for the carcinogenicity of dichlorvos. Overall evaluation: Dichlorvos is possibly carcinogenic to humans (2B).
[IARC. Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Man. Geneva: World Health Organization, International Agency for Research on Cancer,1972-PRESENT. (Multivolume work).,p. 53 296 (1991)]**PEER REVIEWED**

CLASSIFICATION: B2; probable human carcinogen. BASIS FOR CLASSIFICATION: Significant increases in forestomach tumors in female and male B6C3F1 mice and leukemias and pancreatic acinar adenomas in Fischer 344 rats. Supporting evidence included observation of tumors at other sites in the rat and observation of mutagenicity for both dichlorvos and a major metabolite dichloroacetaldehyde. A structurally related material, dichloropropene , also induces forestomach tumors in rodents. HUMAN CARCINOGENICITY DATA: None. ANIMAL CARCINOGENICITY DATA: Sufficient.
[U.S. Environmental Protection Agency's Integrated Risk Information System (IRIS) on Dichlorvos (62-73-7) Available from: http://www.epa.gov/ngispgm3/iris on the Substance File List as of March 15, 2000]**PEER REVIEWED**

 

Human Toxicity Excerpts:

HUMANS EXPOSED AT CONCN ... VARYING FROM 0.14 TO 0.33 MG/CU M FOR 30 MIN EACH HR, 10 HR A DAY FOR 14 DAYS, SHOWED NO CHANGES IN CHOLINESTERASE OR IN NUMBER OF PHYSIOLOGICAL FUNCTIONS. ... ON THE OTHER HAND, WHEN 28 HUMAN VOLUNTEERS WERE EXPOSED TO DICHLORVOS BY INHALATION AT A CONCN OF 1 MG/CU M, SINGLE EXPOSURES OF 7.5-8.5 HR RESULTED IN PLASMA CHOLINESTERASE DEPRESSION OF 20-25%.
[American Conference of Governmental Industrial Hygienists, Inc. Documentation of the Threshold Limit Values and Biological Exposure Indices. 6th ed. Volumes I,II, III. Cincinnati, OH: ACGIH, 1991. 446]**PEER REVIEWED**

... PESTICIDE WORKERS HANDLING DICHLORVOS /WERE SEEN TO HAVE A/ REDUCTION ... IN BLOOD CHOLINESTERASE AS WELL AS LEUKOCYTOSIS, NEUTROPHILIA, & DECR IN LYMPHOCYTES & MONOCYTES. THESE WERE BACK TO NORMAL @ A 2 WK FOLLOW-UP FOLLOWING EXPOSURE.
[American Conference of Governmental Industrial Hygienists. Documentation of the Threshold Limit Values and Biological Exposure Indices. 5th ed. Cincinnati, OH:American Conference of Governmental Industrial Hygienists, 1986. 192]**PEER REVIEWED**

After inhalation of dichlorvos, breathing and eye effects are the first to appear. These include tightness of the chest, wheezing, a bluish discoloration of the skin, small pupils, aching in and behind the eyes, blurring of vision, tearing, runny nose, headache, and watering of the mouth. After /ingestion/ of dichlorvos, loss of appetite, nausea, vomiting, abdominal cramps, and diarrhea may appear within two hours. After skin absorption, sweating and twitching in the area of absorption may occur ... within 15 minutes to four hours. With severe intoxication by all routes, in addition to all the symptoms /previously mentioned/, weakness, generalized twitching, and paralysis may /result/ and breathing may stop. In addition, dizziness, confusion, staggering, slurred speach, generalized sweating, irregular or slow heart beat, convulsions, and coma /may result/.
[Mackison, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (eds.). NIOSH/OSHA - Occupational Health Guidelines for Chemical Hazards. DHHS(NIOSH) PublicationNo. 81-123 (3 VOLS). Washington, DC: U.S. Government Printing Office, Jan. 1981. 1]**PEER REVIEWED**

RAPID DEGRADATION ... BOTH IN AIR & IN BODY, IS PROBABLY RESPONSIBLE FOR WIDE MARGIN BETWEEN THAT CONCN WHICH CAUSES DETECTABLE EFFECT ON MOST SENSITIVE INDICATOR OF EXPOSURE, PLASMA CHOLINESTERASE, & CONCN WHICH PRODUCES NOTICEABLE SYMPTOMS OF ILLNESS.
[American Conference of Governmental Industrial Hygienists, Inc. Documentation of the Threshold Limit Values and Biological Exposure Indices. 6th ed. Volumes I,II, III. Cincinnati, OH: ACGIH, 1991. 447]**PEER REVIEWED**

The potency of dichlorvos to inhibit human complement (C') activities of a panel of normal human sera was investigated in a modified assay using human complement mediated lysis of sheep red cells (1) incorporating suboptimal concn of sensitizing antibody, and (2) exhibiting incr sensitivity to serine esterase inhibitors. Dichlorvos was added to diluted sera 2 hr prior to incorporation into human complement reaction mixtures. Potencies to inhibit human complement and serum cholinesterase were compared to potencies of diisopropylfluorophosphate, a potent serine esterase inhibitor and a standard probe for human complement esterases. At 0.5 to 3.0 mM, dichlorvos produced a dose dependent inhibition of lysis. Mean IC50 for inhibition of cholinesterase (a marker for occupational exposure to organophosphates and carbamates) by dichlorvos was 1.0x10-7 M. Potency of the insecticide to inhibit cholinesterase did not predict absolute or relative potency to inhibit serum human complement activity.
[Casale GP et al; Fundam Appl Toxicol 12 (3): 460-8 (1989)]**PEER REVIEWED**

In man, dichlorvos inhibits plasma cholinesterase more readily than red cell cholinesterase.
[Hayes, Wayland J., Jr. Pesticides Studied in Man. Baltimore/London: Williams and Wilkins, 1982. 345]**PEER REVIEWED**

Mortality surveys and death certificate studies have suggested an association between leukemia and farming. To investigate whether exposure to carcinogens in an agricultural setting is related to risk of leukemia, a population based control interview study of 578 white men with leukemia and 1245 controls living in Iowa and Minnesota /was conducted/. Consistent with recent mortality studies, there were slight, but significant, elevations in risk for all leukemia (odds ratio 1.2) and chronic lymphocytic leukemia (odds ratio 1.4) for farmers compared to nonfarmers. There were no significant associations with leukemia for exposure to specific fungicides, herbicides (including 2,4-D and 2,4,5-T), or crop insecticides. However, significantly elevated risks for leukemia of \ 2.0 were seen for exposure to specific animal insecticides including the organophosphates crotoxyphos (odds ratio 11.1), dichlorvos (odds ratio 2.0), and famphur (odds ratio 2.2) and the natural product pyrethrins (odds ratio 3.7) and the chlorinated hydrocarbon methoxychlor (odds ratio 2.2). There were also smaller, but significant, risks associated with exposure to nicotine (odds ratio 1.6) and DDT (odds ratio 1.3). This finding of elevated risks for insecticides used on animals deserves further evaluation.
[Brown LM et al; Cancer Res 50 (20): 6585-91 (1990)]**PEER REVIEWED**

MUTAGENICITY: SISTER CHROMATID EXCHANGE - IN VITRO CHROMOSOMAL EFFECT STUDIES, HUMAN: NEGATIVE.
[MUTATION RESEARCH 87: 17 (1981)]**PEER REVIEWED**

 

Skin, Eye and Respiratory Irritations:

Dichlorvos is not known to be an eye irritant.
[Mackison, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (eds.). NIOSH/OSHA - Occupational Health Guidelines for Chemical Hazards. DHHS(NIOSH) PublicationNo. 81-123 (3 VOLS). Washington, DC: U.S. Government Printing Office, Jan. 1981. 2]**PEER REVIEWED**

 

Drug Warnings:

VET: DO NOT USE IN CONJUNCTION WITH OR WITHIN FEW DAYS OF (BEFORE &/OR AFTER) ANY OTHER CHOLINESTERASE INHIBITORS & AVOID USE WITH PHENOTHIAZINE, PHENOTHIAZONE TRANQUILIZERS, ARSENICALS, PURGATIVES, OR DRUGS PRODUCING PURGATION AS SIDE EFFECT.
[Rossoff, I.S. Handbook of Veterinary Drugs. New York: Springer Publishing Company, 1974. 166]**PEER REVIEWED**

DO NOT ADMINSTER TASK /A FORMULATION/ ... DOG ANTHELMINTIC IN CONJUNCTION WITH OTHER ANTHELMINTICS, TAENIACIDES, ANTIFILARIAL AGENTS (DIETHYLCARBAMAZINE EXCEPTED), MUSCLE RELAXANTS OR TRANQUILIZERS. /TASK/
[Aronson, C.E. (ed.). Veterinary Pharmaceuticals & Biologicals, 1980-1981. Media, Pa.: Harwal Publishing Co., 1980.,p. 19/76]**PEER REVIEWED**

DO NOT ADMIN TO DOGS SHOWING SIGNS OF SEVERE CONSTIPATION, MECHANICAL BLOCKAGE OF INTESTINAL TRACT, IMPAIRED LIVER FUNCTION, CIRCULATORY FAILURE, OR TO DOGS RECENTLY EXPOSED TO OR SHOWING SIGNS OF INFECTIOUS DISEASES.
[Aronson, C.E. (ed.). Veterinary Pharmaceuticals & Biologicals, 1980-1981. Media, Pa.: Harwal Publishing Co., 1980.,p. 19/76]**PEER REVIEWED**

 

Medical Surveillance:

A complete history and physical examination. ... Examination of the respiratory system, nervous system, cardiovascular system, and attention to the cholinesterase levels in the blood should be stressed. The skin should be examined for chronic disorders. ... The cholinesterase activity in the serum and erythrocytes should be determined by using acceptable biochemical tests prior to any new period of exposure. ... Medical examinations should be repeated on annual basis, with the exception of cholinesterase determination which should be performed quarterly or at any time overexposure is suspected or signs or symptoms of toxicity occur.
[Mackison, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (eds.). NIOSH/OSHA - Occupational Health Guidelines for Chemical Hazards. DHHS(NIOSH) PublicationNo. 81-123 (3 VOLS). Washington, DC: U.S. Government Printing Office, Jan. 1981. 1]**PEER REVIEWED**

... Workers ... must undergo an annual medical exam at the beginning of each agricultural season. Contraindications for work with organophosphorus pesticides are organic diseases of the CNS, mental disorders & epilepsy, pronounced endocrine & vegetative disorders, pulmonary tuberculosis, bronchial asthma, chronic respiratory diseases, cardiovascular diseases and circulatory disorders, gastrointestinal diseases (peptic ulcer), gastroenterocolitis, diseases of the liver & kidneys, eye diseases (chronic conjunctivitis and keratitis). Blood cholinesterase activity must be determined before work starts. In the event of prolonged work periods, this activity should be determined at intervals of 3-4 days. Persons exhibiting a fall in cholinesterase activity of 25% or more must be transferred to other work where they are not exposed ... until /cholinesterase level/ is completely restored. /Organophosphorus pesticides/
[International Labour Office. Encyclopedia of Occupational Health and Safety. Vols. I&II. Geneva, Switzerland: International Labour Office, 1983. 1646]**PEER REVIEWED**

PRECAUTIONS FOR "CARCINOGENS": Whenever medical surveillance is indicated, in particular when exposure to a carcinogen has occurred, ad hoc decisions should be taken concerning ... /cytogenetic and/or other/ tests that might become useful or mandatory. /Chemical Carcinogens/
[Montesano, R., H. Bartsch, E.Boyland, G. Della Porta, L. Fishbein, R. A. Griesemer, A.B. Swan, L. Tomatis, and W. Davis (eds.). Handling Chemical Carcinogens in the Laboratory:Problems of Safety. IARC Scientific Publications No. 33. Lyon, France: International Agency for Research on Cancer, 1979. 23]**PEER REVIEWED**

SERUM OR PLASMA: The literature search did not reveal reports of monitoring tests for assessment of organophosphate pesticide absorption. Reference Ranges: Normal - Not established; Exposed - Not established; Toxic - Not established. /Organophosphate pesticides/
[Ryan, R.P., C.E. Terry (eds.). Toxicology Desk Reference 4th ed. Volumes 1-3. Taylor & Francis, washington, D.C. 1997. 1857]**PEER REVIEWED**

URINE: The assessment of organophosphate pesticide exposure can be accomplished through measurement of the following alkyl phosphate metabolites: dimethylphosphate (DMP), diethylphosphate (DEP), dimethylthiophosphate (DMTP), diethylthiophosphate (DETP), dimethyldithiophosphate (DMDTP), and diethyldithiophosphate (DEDTP). Detection of dimethylphosphate and diethylphosphate have been found to be directly attributable to pesticide exposure. Detection of dimethyldithiophosphate and diethyldithiophosphate is difficult since they are rapidly degraded and are less directly associated with pesticide exposure, while dimethylthiophosphate and diethylthiophosphate levels can be produced from other non-pesticide sources, limiting their usefulness as markers for pesticide absorption. The one limitation to measurement of urinary alkyl metabolites is that this test is only useful for assessing recent exposure, due to the short half-life of organophosphate pesticides. In addition, there are tests for specific urinary phenolic metabolites of certain organophosphate pesticides such as parathion (metabolite, p-nitrophenol). However, since each pesticide gives rise to a different phenol metabolite, it is probably not feasible to identify each urinary metabolite. Reference Ranges: Normal - Not established; Exposed - Not established; Toxic - Not established. /Organophosphate pesticides/
[Ryan, R.P., C.E. Terry (eds.). Toxicology Desk Reference 4th ed. Volumes 1-3. Taylor & Francis, washington, D.C. 1997. 1857]**PEER REVIEWED**

BAT for Acetylcholinesterase inhibitors (sampling time is end of exposure or end of shift, or for long-term exposures sampling time is after several shifts: both measured as acetylcholinesterase in erythrocytes): Reduction of activity to 70% of reference value. /Organophosphate pesticides/
[Ryan, R.P., C.E. Terry (eds.). Toxicology Desk Reference 4th ed. Volumes 1-3. Taylor & Francis, washington, D.C. 1997. 1859]**PEER REVIEWED**

BEI (sampling time is discretionary): 70% of individual's baseline. /Organophosphate pesticides/
[Ryan, R.P., C.E. Terry (eds.). Toxicology Desk Reference 4th ed. Volumes 1-3. Taylor & Francis, washington, D.C. 1997. 1859]**PEER REVIEWED**

Urine Albumin: Albuminuria has been shown to be a specific marker of glomerular dysfunction. Tubular damage, however, can also result in increased levels of albumin in the urine. /Organophosphate pesticides/
[Ryan, R.P., C.E. Terry (eds.). Toxicology Desk Reference 4th ed. Volumes 1-3. Taylor & Francis, washington, D.C. 1997. 1859]**PEER REVIEWED**

Urinary Beta-2-Microglobulin and/or Retinal Binding Protein (RBP): Measurements for the presence of either of these low molecular weight proteins are useful in detection of early impairment of proximal tubular function. However, beta-2-microglobulin is unstable at urinary pH less than 6, and may degrade in the bladder prior to collection and subsequent neutralization of the urine sample. Measurement of RBP appears to be a better marker for early tubular dysfunction due to its stability in the urine subsequent to collection and analysis. However, RBP is produced in the liver and not a constitutive protein of the kidney, so that its presence in the kidney provides only indirect evidence of tubular damage.
[Ryan, R.P., C.E. Terry (eds.). Toxicology Desk Reference 4th ed. Volumes 1-3. Taylor & Francis, washington, D.C. 1997. 1859]**PEER REVIEWED**

Urinary Alpha and Pi Isoenzymes of Glutathione S-Transferase: Radio-immunological and Elisa techniques have been developed for quantitation of and isoenzymes of glutathione S-transferase (GST), which are constitutive proteins in the kidney. The isoenzyme is located only in the proximal tubule, while the isoenzyme is located in the distal convoluted tubule, the loop of Henle, and the collecting ducts of the kidney. Damage to epithelial cell membranes can result in the increased excretion of these isoenzymes in the urine. This test for assessing renal tubular damage appears to have many advantages over other available tests, such as: (1) the alpha and pi isoenzymes are constitutive proteins in the kidney; (2) these isoenzymes are stable in the urine; (3) the test is simple and reproducible; and (4) due to selective localization of the isoenzymes, differential diagnosis of specific tubular damage is possible. In addition, increased levels of these isoenzymes were seen in patients previously exposed to nephrotoxicants where conventional tests for kidney function were normal, indicating a high degree of sensitivity. /Organophosphate pesticides/
[Ryan, R.P., C.E. Terry (eds.). Toxicology Desk Reference 4th ed. Volumes 1-3. Taylor & Francis, washington, D.C. 1997. 1859]**PEER REVIEWED**

Urinary Enzyme N-acetylglucosaminidase: This lysosomal enzyme has shown promise in assessment of subclinical nephrotoxic injury. This enzyme is not normally filtered at the glomerulus due to its high molecular weight. In the absence of glomerular injury, this enzyme will be detected in the urine as a result of leakage or exocytosis from damaged, stimulated, or exfoliated renal cells. The sensitivity of measurement for this enzyme has not been thoroughly studied, but its usefulness has shown some promise. However, this enzyme is unstable at urinary pH greater than 8, which could diminish the sensitivity of measurement due to enzyme degradation. /Organophosphate pesticides/
[Ryan, R.P., C.E. Terry (eds.). Toxicology Desk Reference 4th ed. Volumes 1-3. Taylor & Francis, washington, D.C. 1997. 1860]**PEER REVIEWED**

Routine Urinalysis: Performing a routine urinalysis including parameters such as specific gravity, glucose, and a microscopic examination may be useful for assessing renal toxicity. /Organophosphate pesticides/
[Ryan, R.P., C.E. Terry (eds.). Toxicology Desk Reference 4th ed. Volumes 1-3. Taylor & Francis, washington, D.C. 1997. 1860]**PEER REVIEWED**

Evaluation of Peripheral Neuropathy: nerve conduction study, electromyography (EMG), quantitative sensory testing, thermography. /Organophosphate pesticides/
[Ryan, R.P., C.E. Terry (eds.). Toxicology Desk Reference 4th ed. Volumes 1-3. Taylor & Francis, washington, D.C. 1997. 1861]**PEER REVIEWED**

Evaluation of Central Nervous System Effects: Evaluation of CNS effects can be performed through neuropsychological assessment, which consists of a clinical interview and administration of standardized personality and neuropsychological test. The areas that the neuropsychology test batteries focus on include the domains of memory and attention; visuoperceptual, visual scanning, visuospatial, and visual memory; and motor speed and reaction time. There is limited data on which components of the test batteries are best indicators of early CNS effects. /Organophosphate pesticides/
[Ryan, R.P., C.E. Terry (eds.). Toxicology Desk Reference 4th ed. Volumes 1-3. Taylor & Francis, washington, D.C. 1997. 1862]**PEER REVIEWED**

Evaluation of Cranial Neuropathies: Evaluation of cranial nerve damage, as evidenced by symptoms such as loss of balance, visual function, smell, taste, or sensation on the face, can be accomplished through a physical examination focusing on tests such as: smell assessment - standardized odor threshold and identification testing; vision assessment - standard acuity test, visual field tests, contrast sensitivity, and color vision measurements (vision assessment); facial and trigeminal nerve assessment - blink reflex (pontogram); vestibular assessment - pure tone audiometry for bone- and air-conducted sounds, threshold decay at 4 kHz, speech discrimination and speech reception thresholds, tympanograms and acoustic thresholds, electronystagmograms; hearing assessment - audiometry testing. /Organophosphate pesticides/
[Ryan, R.P., C.E. Terry (eds.). Toxicology Desk Reference 4th ed. Volumes 1-3. Taylor & Francis, washington, D.C. 1997. 1862]**PEER REVIEWED**

 

Populations at Special Risk:

... Persons with a history of reduced pulmonary function, convulsive disorders, or recent exposure to anticholinesterase agents would be expected to be at increased risk from exposure.
[Mackison, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (eds.). NIOSH/OSHA - Occupational Health Guidelines for Chemical Hazards. DHHS(NIOSH) PublicationNo. 81-123 (3 VOLS). Washington, DC: U.S. Government Printing Office, Jan. 1981. 1]**PEER REVIEWED**

DICHLORVOS IS RAPIDLY INACTIVATED BY ... LIVER ENZYMES. ... PATIENTS WITH HEPATIC INSUFFICIENCY MAY BE LESS TOLERANT TO THE TOXIC EFFECTS OF DICHLORVOS.
[Gosselin, R.E., R.P. Smith, H.C. Hodge. Clinical Toxicology of Commercial Products. 5th ed. Baltimore: Williams and Wilkins, 1984.,p. II-291]**PEER REVIEWED**

Work ... must not be carried out by young persons under 18 yr, expectant or nursing mothers, or persons for whom work with toxic chemicals is contraindicated on account of their state of health; the same applies to alcoholics. Contraindications for work with organophosphorus pesticides are organic diseases of the CNS, mental disorders & epilepsy, pronounced endocrine & vegetative disorders, pulmonary tuberculosis, bronchial asthma, chronic respiratory diseases, cardiovascular diseases and circulatory disorders, gastrointestinal diseases (peptic ulcer), gastroenterocolitis, diseases of the liver & kidneys, eye diseases (chronic conjunctivitis and keratitis). /Organophosphorus pesticides/
[International Labour Office. Encyclopedia of Occupational Health and Safety. Vols. I&II. Geneva, Switzerland: International Labour Office, 1983. 1646]**PEER REVIEWED**

 

Probable Routes of Human Exposure:

Dichlorvos can affect the body if it is inhaled, if it comes in contact with the eyes or skin, or is swallowed. ...
[Mackison, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (eds.). NIOSH/OSHA - Occupational Health Guidelines for Chemical Hazards. DHHS(NIOSH) PublicationNo. 81-123 (3 VOLS). Washington, DC: U.S. Government Printing Office, Jan. 1981. 1]**PEER REVIEWED**

NIOSH (NOES Survey 1981-1983) has statistically estimated that 11,182 workers (2,182 of these are female) are potentially exposed to dichlorvos in the US(1). The NOES Survey does not include agricultural workers. Occupational exposure to dichlorvos may occur through inhalation of ambient air and dermal contact with this compound at workplaces where dichlorvos is produced or used for household and public health insect control, flea collars and no-pest strips(2,SRC). Similarly, the general population may be exposed to dichlorvos via inhalation of air and dermal contact when no-pest strips, sprays or flea collars containing this insecticide are used. Exposure could also result from ingestion of food which has been prepared in rooms where dichlorvos is used for insect control(SRC). As part of EPA's Non-Occupational Pesticide Exposure Study (NOPES) conducted in the Summer 1986, Spring 1987 and Winter 1988 in Jacksonville, FL and Springfield/Chicopee, MA the estimated mean personal air concn of dichlorvos for Jacksonville residents was 147.6, 40.2, and 21.4 ng/cu m in summer, spring and winter, respectively(3). The estimated spring and winter concns for Springfield/Chicopee residents were 3.7 and 2.1 ng/cu m in spring and winter. In Jacksonville, it was estimated that the percentage of residents with detectable levels of dichlorvos in personal air was 35%, 11%, and 16% in summer, spring and winter, respectively. In Springfield/Chicopee only 2% and 1% of residents were exposed in spring and winter. Exposure from air inhalation was the primary route of exposure to dichlorvos(3).
[(1) NIOSH; National Occupational Exposure Survey (NOES) (1983) (2) Lewis RG et al; APCA Annual Meeting #79 Research Triangle Park,NC: USEPA 2: 15 (1986) (3) Whitmore RW et al; Arch Environ Contam Toxicl 26: 47-59 (1994)]**PEER REVIEWED**

Dichlorvos was detected in the workplace environment in concns of 77 ppb in air during production and processing of a dichlorvos-releasing vaporizer(1). During spraying of an orchard 130 ppb was detected in air and a rate of skin contamination of 72 ug/100 sq cm/hr was reported(1). After spraying, 114-765 ug/sq m of dichlorvos was deposited on worker's clothing(3). A study was performed to determine the level of exposure to 5 workers after 1.85 kg of dichlorvos was sprayed on an apple orchard for 5.5 hr with an airblast sprayer(4). The air and breathing zone dichlorvos concns were 1.0-15.4 ug/cu m, and 113.6-765.3 ug/cu m, respectively. Ambient air in storage rooms of four North Carolina commercial pest control firms (4 hr period) contained 147-1501 ng/cu m, (617 ng/cu m avg)(2). Ambient air in offices of four North Carolina commercial pest control firms (4 hr period) contained 19-66 ng/cu m, (41 ng/cu m avg)(2). A 1993 study of insecticide concns in the air of 10 North Carolina pest control firms (19 samples) resulted in mean dichlorvos air levels of 1.48 ug/cu m(5). Levels were higher in summer than in winter. In a study to determine the dissipation of dislodgeable residues of dichlorvos on turf, the residue level was 0.10 ug/sq cm immediately post application (<2 hr) and rapidly declined to below the safe level for reentry, 0.06 mg/sq cm after two hours and was undetectable (<1 ug/sample) after 23 hr(5). There was no significant difference in post application dissipation of dislodgeable residues between irrigated and non-irrigated plots. Dichlorvos was detected in air samples immediately post-spray at 1.9 ppb(5). Three hours after application of dichlorvos to greenhouse crops using low-volume (<50 l/ha) techniques, the atmospheric concn of dichlorvos had declined to 12% of the initial concn but was still exceeding the 1000 ug/cu m threshold limit value (TLV)(6).
[(1) IARC; Some Halogenated Hydrocarbons 20 (1979) (2) Wright CG, Leidy RB; Bull Environ Contam Toxicol 24: 582-9 (1980) (3) Okuno T et al; Kankyo Kagaku 4: 470-1 (1994) (4) Okuno T et al; Hyogo-kenritsu Eisei Kenkyusho Nenpo 31: 73-80 (1996) (5) Wright CG et al; Bull Environ Contam Toxicol 56: 21-8 (1996) (6) Brouwer DH et al; Chemosphere 24: 1157-69 (1992)]**PEER REVIEWED**

 

Body Burden:

Two pest control operators in Japan involved in spraying and mixing a combined emulsifiable concentrate of fenithrothion and dichlorvos to exterminated cockroaches in household construction contained mean and maximum alkyl phosphate levels in urine of 0.099 and 0.22 ug/mg creatinine(1).
[(1) Takamiya K; Bull Environ Contam Toxicol 52:190-5 (1994)]**PEER REVIEWED**

 

Average Daily Intake:

AIR INTAKE: 1.25 ug (Jacksonville, FL; assuming a weighted estimate of average daily air concns of 62.4 ng/cu m(1)); 0.066 ug (Springfield/Chicopee, MA; assuming a weighted estimate of average daily air concns of 3.3 ng/cu m(1)).
[(1) Whitmore RW et al; Arch Environ Contam Toxicl 26: 47-59 (1994)]**PEER REVIEWED**

 

Emergency Medical Treatment:

 

 

Emergency Medical Treatment:

 

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The following Overview, *** DICHLORVOS ***, is relevant for this HSDB record chemical.

Life Support:
  o   This overview assumes that basic life support measures
      have been instituted.                           
Clinical Effects:
  SUMMARY OF EXPOSURE
   0.2.1.1 ACUTE EXPOSURE
     o   Dichlorvos is a very toxic poison by ingestion,
         inhalation and eye or dermal  contact.  The most common
         route of exposure is spillage on the skin, followed  by
         rapid absorption through the skin.  Inhalation is the
         second most common  route; oral exposure is usualy only
         by accident or suicide.  Dichlorvos  exposure symptoms
         have a remarkably rapid onset and recovery.
     o   The following are general symptoms due to
         anticholinesterase activity of the organophosphate
         class of compounds.  Not all of these effects may be
         documented for dichlorvos, but could potentially occur
         in individual cases.
      1.  MUSCARINIC EFFECTS (PARASYMPATHETIC) - Bradycardia,
          hypotension, bronchospasm, bronchorrhea, salivation,
          lacrimation, diaphoresis, urinary incontinence,
          vomiting, diarrhea, miosis.
      2.  NICOTINIC EFFECTS (SYMPATHETIC/MOTOR) - Tachycardia,
          hypertension, fasciculations, muscle cramps,
          mydriasis, weakness, respiratory paralysis.
      3.  CENTRAL EFFECTS - CNS depression, agitation,
          confusion, restlessness, anxiety, headache, psychosis,
          delirium, coma, seizures.
     o   CHILDREN may have different predominant signs/symptoms
         than adults:  CNS depression, stupor, flaccidity,
         dyspnea, and coma are the most common.  Classic
         muscarinic signs may not develop.
     o   Inhalation of dichlorvos may result in chest tightness,
         wheezing, cyanosis, miosis, aching in and behind the
         eyes, blurred vision, tearing, rhinorrhea, headache,
         and excessive salivation.  Symptoms after ingestion may
         include anorexia, nausea, vomiting, abdominal cramps,
         and diarrhea.  Sweating and twitching in the area of
         absorption may occur following dermal exposure.
     o   Severe intoxication from all routes of exposure may
         include, in addition to all previously mentioned signs
         and symptoms, weakness, generalized twitching,
         paralysis, dizziness, slurred speech, generalized
         sweating, irregular or slow heart beat, seizures, and
         coma.
     o   Because dichlorvos is an organic ester of phosphoric
         acid, it does not require metabolism to an active form
         and may produce rapid onset of symptoms.  Because of
         its rapid metabolic detoxification, dichlorvos has an
         unusually wide margin between inhibition of serum
         cholinesterase and onset of clinical effects; recovery
         is also rapid relative to other organophosphates.
     o   Hydrocarbon diluents and/or impurities in formulated
         pesticides can enhance or contribute to toxicity.
  VITAL SIGNS
   0.2.3.1 ACUTE EXPOSURE
     o   Vital sign changes can include bradycardia or
         tachycardia, hypotension or hypertension, tachypnea,
         respiratory paralysis or fever.
  HEENT
   0.2.4.1 ACUTE EXPOSURE
     o   Miosis, lacrimation, blurred vision and salivation are
         common; mydriasis may occur in severe poisonings.
  CARDIOVASCULAR
   0.2.5.1 ACUTE EXPOSURE
     o   Bradycardia or tachycardia, hypotension, cyanosis and
         chest pain may occur.  Arrhythmias and conduction
         defects may occur in severe cases.
  RESPIRATORY
   0.2.6.1 ACUTE EXPOSURE
     o   Dyspnea, rales, bronchorrhea, tachypnea, Cheyne-Stokes
         respiration, or apnea  may occur, with pulmonary edema
         or paralysis of respiratory muscles and death in severe
         cases.
     o   Bronchospasm may occur in previously sensitized
         asthmatics or as a muscarinic effect.
     o   Acute respiratory insufficiency is the main cause of
         death in acute poisonings.
  NEUROLOGIC
   0.2.7.1 ACUTE EXPOSURE
     o   Headache, dizziness, muscle spasms, profound weakness,
         paralysis, confusion,  slurred speech and loss of
         reflexes are common symptoms of dichlorvos
         overexposure.  Altered level of consciousness, seizures
         and coma may occur.   Seizures may be more common in
         children.
     o   Delayed neuropathy has been reported.
  GASTROINTESTINAL
   0.2.8.1 ACUTE EXPOSURE
     o   Vomiting, diarrhea, fecal incontinence, pancreatitis
         and abdominal pain may  occur after exposure to
         dichlorvos.
  GENITOURINARY
   0.2.10.1 ACUTE EXPOSURE
     o   Increased urinary frequency or incontinence may occur
         after exposure to  dichlorvos.
  ACID-BASE
   0.2.11.1 ACUTE EXPOSURE
     o   Metabolic acidosis may occur in severe poisonings.
  HEMATOLOGIC
   0.2.13.1 ACUTE EXPOSURE
     o   Alteration in prothrombin time and/or tendency to
         bleeding may occur.
  DERMATOLOGIC
   0.2.14.1 ACUTE EXPOSURE
     o   Sweating is a consistent but not universal sign.
     o   Rare cases of primary irritant contact dermatitis have
         occurred; dichlorvos may induce allergic contact
         dermatitis.
  MUSCULOSKELETAL
   0.2.15.1 ACUTE EXPOSURE Muscle weakness, fatigability and
       twitching may occur after dichlorvos exposure.
  ENDOCRINE
   0.2.16.1 ACUTE EXPOSURE
     o   Hyperglycemia and glycosuria (with or without ketosis)
         may occur in severe poisoning.
  METABOLISM
   0.2.17.1 ACUTE EXPOSURE
     o   The hallmark of organophosphate poisoning is inhibition
         of plasma pseudocholinesterase or erythrocyte
         acetylcholinesterase, or both.
  PSYCHIATRIC
   0.2.18.1 ACUTE EXPOSURE
     o   Decreased vigilance, hallucinations, defects in
         expressive language and cognitive function, impaired
         memory, depression, anxiety or irritability and
         psychosis have been reported, more commonly in persons
         having other clinical signs of organophosphate
         poisoning.
  IMMUNOLOGIC
   0.2.19.1 ACUTE EXPOSURE
     o   Pesticide workers exposed to dichlorvos were reported
         to have temporary  leukocytosis, neutrophilia and a
         decrease in lymphocytes and monocytes; this  resolved
         in 2 weeks (HSDB, 2000).
  REPRODUCTIVE HAZARDS
    o   Studies have produced conflicting results on the
        teratogenicity of dichlorvos;  there is evidence of
        links to specific developmental abnormalities in
        experimental animals.  Dichlorvose also increased
        post-implantation mortality  and fetotoxiticity in
        rabbits, and produced changes in rat and mouse
        spermatogenesis.
    o   It does not appear in the milk of cattle or rats.
    o   Sporadic reports of human birth defects related to
        organophosphates have not  been fully verified.
  CARCINOGENICITY
   0.2.21.1 IARC CATEGORY
     o   IARC (Dichlorvos) (IARC, 1997) -
      1.  Human:  Inadequate evidence; Experimental animals:
          Sufficient evidence.
      2.  Group 2B:  "possibly carcinogenic to humans"
   0.2.21.2 HUMAN OVERVIEW
     o   Dichlorvos has been categorized as a "probable human
         carcinogen", as "possibly  carcinogenic to humans", and
         as having inadequate data to determine its
         carcinogenic classification.
   0.2.21.3 ANIMAL OVERVIEW
     o   Dichlorvos is considered carcinogenic and neoplastic by
         RTECS criteria for rats  and mice.  However, studies
         have produced conflicting results about the
         tumorigenicity of dichlorvos in experimental animals.
  GENOTOXICITY
    o   Dichlorvos has reportedly induced DNA damage, repair,
        and unsceduled synthesis, mutations, chromosome
        aberrations and sister chromatid exchanges, sex
        chromosome loss and nondisjunction, and morphological
        transformations in  short-term assays in vitro.
Laboratory:
  o   Dichlorvos is not detectable in tissues because of its
      rapid degradation.
  o   Determine plasma and red blood cell cholinesterase
      activities.  Although there  may be poor correlation
      between cholinesterase values and clinical effects, a
      depression in excess of 50 percent activity is generally
      associated with  severe symptoms.  The correlation between
      cholinesterase levels and clinical  effects in milder
      poisonings may be poor.
  o   Monitor cardiac rhythm, pulse oximetry and arterial blood
      gasses, and follow chest X-rays in patients with
      substantial respiratory or nicotinic signs or  symptoms.
Treatment Overview:
  SUMMARY EXPOSURE
    o   Suction oral secretions as required until atropinization
        is achieved.
    o   Atropinization should rapidly be performed, concurrently
        with decontamination measures.
    o   Pralidoxime (Protopam, 2-PAM) should be administered to
        seriously ill organophosphate-poisoned patients.
    o   If induction of paralysis with muscle relaxing agents is
        required for intubation, succinylcholine should be
        avoided because of potential prolonged duration of
        paralysis secondary to pseudocholinesterase inhibition
        by the organophosphate.
  ORAL EXPOSURE
    o   Inducing emesis is CONTRAINDICATED because of possible
        respiratory depression and seizures.
    o   GASTRIC LAVAGE:  Consider after ingestion of a
        potentially life-threatening amount of poison if it can
        be performed soon after ingestion (generally within 1
        hour).  Protect airway by placement in Trendelenburg and
        left lateral decubitus position or by endotracheal
        intubation.  Control any seizures first.
     1.  CONTRAINDICATIONS:  Loss of airway protective reflexes
         or decreased level of consciousness in unintubated
         patients; following ingestion of corrosives;
         hydrocarbons (high aspiration potential); patients at
         risk of hemorrhage or gastrointestinal perforation; and
         trivial or non-toxic ingestion.
    o   ACTIVATED CHARCOAL:  Administer charcoal as slurry (240
        mL water/30 g charcoal).  Usual dose:  25 to 100 g in
        adults/adolescents, 25 to 50 g in children (1 to 12
        years), and 1 g/kg in infants less than 1 year old.
    o   Suction oral secretions until atropinization.
    o   ATROPINE THERAPY - If symptomatic, administer IV
        atropine until atropinization is achieved.  Adult - 2 to
        5 mg every 10 to 15 minutes; Child - 0.05 mg/kg every 10
        to 15 minutes.  Atropinization may be required for hours
        to days depending on severity.
    o   PRALIDOXIME (Protopam, 2-PAM):  Treat moderate to severe
        poisoning (fasciculations, muscle weakness, respiratory
        depression, coma, seizures) with 2-PAM in addition to
        atropine; most effective if given within 48 hours, but
        has had efficacy up to 6 days.  May require
        administration for several days.
     1.  INITIAL DOSE:  ADULT:  1 to 2 g in 100 to 150 ml 0.9%
         saline IV over 30 min.   CHILD:  20 to 50 mg/kg as a 5%
         solution IV over 30 min.
     2.  Repeat these doses in 1 hour and then every 6 to 12
         hours if  muscle weakness or fasciculations persist, or
         begin continuous infusion.
     3.  CONTINUOUS INFUSION:  Administer as a 2.5% solution in
         0.9% saline.  ADULT:   500 mg/hour.  CHILD:  9 to 19
         mg/kg/hour.
    o   CONTRAINDICATIONS - Succinylcholine and other
        cholinergic agents.
    o   SEIZURES:  Administer a benzodiazepine IV; DIAZEPAM
        (ADULT:  5 to 10 mg,  repeat every 10 to 15 min as
        needed.  CHILD:  0.2 to 0.5 mg/kg, repeat every  5 min
        as needed) or LORAZEPAM (ADULT:  4 to 8 mg; CHILD:  0.05
        to 0.1 mg/kg).
     1.  Consider phenobarbital if seizures recur after diazepam
         30 mg (adults)  or 10 mg (children > 5 years).
     2.  Monitor for hypotension, dysrhythmias, respiratory
         depression, and need  for endotracheal intubation.
         Evaluate for hypoglycemia, electrolyte disturbances,
         hypoxia.
    o   PULMONARY EDEMA (NONCARDIOGENIC):  Maintain ventilation
        and oxygenation and evaluate with frequent arterial
        blood gas or pulse oximetry monitoring.  Early use of
        PEEP and mechanical ventilation may be needed.
    o   HYPOTENSION:  Infuse 10 to 20 mL/kg isotonic fluid,
        place in Trendelenburg position.  If hypotension
        persists, administer dopamine (5 to 20 mcg/kg/min) or
        norepinephrine (0.1 to 0.2 mcg/kg/min), titrate to
        desired response.
  INHALATION EXPOSURE
    o   INHALATION:  Move patient to fresh air.  Monitor for
        respiratory distress.  If cough or difficulty breathing
        develops, evaluate for respiratory tract irritation,
        bronchitis, or pneumonitis.  Administer oxygen and
        assist ventilation as required.  Treat bronchospasm with
        beta2  agonist and corticosteroid aerosols.
    o   If respiratory tract irritation or respiratory
        depression is evident, monitor arterial blood gases,
        chest x-ray, and pulmonary function tests.
    o   Carefully observe patients with inhalation exposure for
        the development of any systemic signs or symptoms and
        administer symptomatic treatment as necessary.
    o   Suction oral secretions until atropinization.
    o   Treatment should include recommendations listed in the
        ORAL EXPOSURE section when appropriate.
    o   CONTRAINDICATIONS - Succinylcholine and other
        cholinergic agents are contraindicated.
  EYE EXPOSURE
    o   DECONTAMINATION:  Irrigate exposed eyes with copious
        amounts of tepid water for at least 15 minutes.  If
        irritation, pain, swelling, lacrimation, or photophobia
        persist, the patient should be seen in a health care
        facility.
    o   Patients symptomatic following exposure should be
        observed in a controlled setting until all signs and
        symptoms have fully resolved.
    o   Suction oral secretions until atropinization.
    o   Treatment should include recommendations listed in the
        ORAL EXPOSURE section when appropriate.
    o   CONTRAINDICATIONS - Succinylcholine and other
        cholinergic agents are contraindicated.
  DERMAL EXPOSURE
    o   Systemic effects can occur from dermal exposure to
        organophosphates.
    o   Remove contaminated clothing and jewelry; wash skin,
        hair and nails vigorously with repeated soap washings.
        Leather absorbs pesticides; all contaminated leather
        should be discarded.  Rescue personnel and bystanders
        should avoid direct contact  with contaminated skin,
        clothing, or other objects.
    o   Treatment should include recommendations listed in the
        ORAL EXPOSURE section when appropriate.
    o   Some chemicals can produce systemic poisoning by
        absorption through intact skin.  Carefully observe
        patients with dermal exposure for the development of any
        systemic signs or symptoms and administer symptomatic
        treatment as necessary.
    o   CONTRAINDICATIONS - Succinylcholine and other
        cholinergic agents are contraindicated.
Range of Toxicity:
  o   Decreases in serum and erythrocyte cholinesterase
      activities without adverse clinical effects have been
      reported from occupational exposures.
  o   Acute toxicity is variable and depends strongly on the
      kinetics of absorption and whether or not metabolic
      activation is required.  Sudden absorption of a less toxic
      compound may have a more severe effect than gradual
      absorption of a more toxic compound.


[Rumack BH: POISINDEX(R) Information System. Micromedex, Inc., Englewood, CO, 2001; CCIS Volume 110, edition exp November, 2001. Hall AH & Rumack BH (Eds):TOMES(R) Information System. Micromedex, Inc., Englewood, CO, 2001; CCIS Volume 110, edition exp November, 2001.] **PEER REVIEWED**

 

Antidote and Emergency Treatment:

Exptl Therapy: Acidosis in dogs /resulting from/ poisoning with DDVP (30 mg/kg iv) was treated effectively by injections of sodium bicarbonate (10 milliequivalent IV/kg IV, given in 3 injections). Sodium bicarbonate increased the survival rate of DDVP poisoned dogs to 84.62%. ...
[Cordoba D et al; Vet Hum Toxicol 25 (1): 1-3 (1983)]**PEER REVIEWED**

Exptl Therapy: Diethyxime, a non-quaternary cholinesterase reactivator was evaluated for its antidotal efficacy against organophosphorus intoxication in rats using the protection index, cholinesterase reactivation and neuromuscular function as the experimental protocol. Diethyxime along with atropine produced a marked antidote against dichlorvos on all the parameters studied. The action of diethyxime was mainly peripheral. ...
[Dube SN et al; Jpn J Pharmacol 41 (3): 267-71 (1986)]**PEER REVIEWED**

Basic treatment: Establish a patent airway. Suction if necessary. Aggressive airway control may be needed. Watch for signs of respiratory insufficiency and assist ventilations if necessary. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for pulmonary edema and treat if necessary ... . Monitor for shock and treat if necessary ... . Anticipate seizures and treat if necessary ... . For eye contamination, flush eyes immediately with water. Irrigate each eye continuously with normal saline during transport ... . Do not use emetics. For ingestion, rinse mouth and administer 5 mL/kg up to 200 mL of water for dilution if the patient can swallow, has a strong gag reflex, and does not drool. Administer activated charcoal ... . /Organophosphates and Related Compounds/
[Bronstein, A.C., P.L. Currance; Emergency Care for Hazardous Materials Exposure. 2nd ed. St. Louis, MO. Mosby Lifeline. 1994. 259]**PEER REVIEWED**

Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious or has severe pulmonary edema. Positive-pressure ventilation techniques with a bag-valve-mask device may be beneficial. Monitor cardiac rhythm and treat arrhythmias if necessary ... . Start an IV with D5W TKO /SRP: "To keep open", minimal flow rate/. Use lactated Ringer's if signs of hypovolemia are present. Administer atropine. Correct hypoxia before giving atropine ... . Administer pralidoxime chloride (2 PAM). USE UNDER DIRECT PHYSICIAN ORDERS ONLY ... . Treat seizures with adequate atropinization and correction of hypoxia. Rarely is diazepam necessary ... . For hypotension with signs of hypovolemia, administer fluid cautiously and consider vasopressors for hypotension with a normal fluid volume. Watch for signs of fluid overload ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Organophosphates and Related compounds/
[Bronstein, A.C., P.L. Currance; Emergency Care for Hazardous Materials Exposure. 2nd ed. St. Louis, MO. Mosby Lifeline. 1994. 259]**PEER REVIEWED**

1. INSURE THAT A CLEAR AIRWAY EXISTS BY ASPIRATION OF SECRETIONS IF NECESSARY. ADMIN OXYGEN BY MECHANICALLY ASSISTED PULMONARY VENTILATION IF RESPIRATION IS DEPRESSED. IMPROVE TISSUE OXYGENATION AS MUCH AS POSSIBLE BEFORE ADMIN ATROPINE TO MINIMIZE RISK OF VENTRICULAR FIBRILLATION. IN SEVERE POISONINGS, IT MAY BE NECESSARY TO SUPPORT PULMONARY VENTILATION MECHANICALLY FOR SEVERAL DAYS. 2. ADMIN ATROPINE SULFATE IV, OR IM IF IV INJECTION IS NOT POSSIBLE. ... IN MODERATELY SEVERE POISONING: ADULT DOSAGE AND CHILDREN OVER 12 YR: 0.4-2.0 MG REPEATED EVERY 15 MIN UNTIL ATROPINIZATION IS ACHIEVED. MAINTAIN ATROPINIZATION WITH REPEATED DOSAGE OF 0.02-0.05 MG/KG BODY WEIGHT. /ORGANOPHOSPHATE PESTICIDES/
[MORGAN DP; RECOGNITION AND MANAGEMENT OF PESTICIDE POISONINGS. 4TH ED, P. 6 EPA 540/9-88-001. WASHINGTON, DC, U.S. GOVERNMENT PRINTING OFFICE, MARCH 1989]**PEER REVIEWED**

2. SEVERELY POISONED INDIVIDUALS MAY EXHIBIT REMARKABLE TOLERANCE TO ATROPINE; TWO OR MORE TIMES THE DOSAGES SUGGESTED ABOVE MAY BE NEEDED. THE DOSE OF ATROPINE MAY BE INCREASED AND THE DOSING INTERVAL DECREASED AS NEEDED TO CONTROL SYMPTOMS. CONTINUOUS INTRAVENOUS INFUSION OF ATROPINE MAY BE NECESSARY WHEN ATROPINE REQUIREMENTS ARE MASSIVE. REVERSAL OF MUSCARINIC SYMPTOMS AND SIGNS, NOT AN ARBITRARY DOSE LIMIT, IS THE DESIRED END POINT. PRESERVATIVE-FREE ATROPINE PRODUCTS SHOULD BE USED WHENEVER POSSIBLE. NOTE: PERSONS NOT POISONED OR ONLY SLIGHTLY POISONED BY ORGANOPHOSPHATES MAY DEVELOP SIGNS OF ATROPINE TOXICITY FROM SUCH LARGE DOSES. FEVER, MUSCLE FIBRILLATIONS, AND DELIRIUM ARE THE MAIN SIGNS OF ATROPINE TOXICITY. IF THESE APPEAR WHILE THE PATIENT IS FULLY ATROPINIZED, ATROPINE ADMINISTRATION SHOULD BE DISCONTINUED, AT LEAST TEMPORARILY, WHILE THE SEVERITY OF POISONING IS REEVALUATED. /ORGANOPHOSPHATE PESTICIDES/
[MORGAN DP; RECOGNITION AND MANAGEMENT OF PESTICIDE POISONINGS. 4TH ED, P.7 EPA 540/9-88-001. WASHINGTON, DC: U.S. GOVERNMENT PRINTING OFFICE, MARCH 1989]**PEER REVIEWED**

3. DRAW BLOOD SAMPLE (HEPARINIZED) FOR CHOLINESTERASE ANALYSIS BEFORE ADMINISTRATION OF PRALIDOXIME, WHICH TENDS TO REVERSE THE CHOLINESTERASE DEPRESSION. 4. ADMIN PRALIDOXIME (PROTOPAM, 2-PAM) IN CASES OF SEVERE POISONING ... IN WHICH RESP DEPRESSION, MUSCLE WEAKNESS & TWITCHINGS ARE SEVERE. ... ADULT DOSAGE AND CHILDREN OVER 12): GIVE 1.0-2.0 G IV @ NO MORE THAN 0.2 G/MIN. CHILD'S DOSE (UNDER 12 YR): GIVE 20-50 MG/KG (DEPENDING ON SEVERITY) IV, INJECTING NO MORE THAN HALF TOTAL DOSE/MIN. DOSAGE...MAY BE REPEATED IN 1-2 HR, THEN @ 10-12 HR INTERVAL IF NEEDED. IN VERY SEVERE POISONINGS, DOSAGE...MAY BE DOUBLED. /ORGANOPHOSPHATE PESTICIDES/
[MORGAN DP; RECOGNITION AND MANAGEMENT OF PESTICIDE POISONINGS. 4TH ED, P.7 EPA 540/9-88-001. WASHINGTON, DC: U.S. GOVERNMENT PRINTING OFFICE, MARCH 1989]**PEER REVIEWED**

4. BE PREPD TO ASSIST PULMONARY VENTILATION MECHANICALLY IF RESP ... DEPRESSED ... . 5. IN PATIENTS WHO HAVE BEEN POISONED BY ORGANOPHOSPHATE CONTAMINATION OF SKIN, CLOTHING, HAIR, AND/OR EYES, DECONTAMINATION MUST PROCEED CONCURRENTLY WITH WHATEVER RESUSCITATIVE AND ANTIDOTAL MEASURES ARE NECESSARY TO PRESERVE LIFE. ... 6. IF ... INGESTED IN QUANTITY PROBABLY SUFFICIENT TO CAUSE POISONING, THE STOMACH AND INTESTINE MUST BE EMPTIED. A. EMPTY THE STOMACH BY INTUBATION, ASPIRATION, AND LAVAGE, USING SLURRY OF ACTIVATED CHARCOAL IN ISOTONIC SALINE. RIGOROUS PRECAUTIONS MUST BE TAKEN TO PROTECT THE AIRWAY FROM ASPIRATION OF REGURGITATED GASTRIC CONTENTS. IF VICTIM IS UNCONSCIOUS OR OBTUNDED, INSERT A CUFFED ENDOTRACHEAL TUBE PRIOR TO GASTRIC INTUBATION. KEEP VICTIM'S HEAD BELOW LEVEL OF STOMACH DURING GASTRIC INTUBATION AND LAVAGE ... . KEEP VICTIM'S HEAD TURNED TO THE LEFT. /ORGANOPHOSPHATE PESTICIDES/
[MORGAN DP; RECOGNITION AND MANAGEMENT OF PESTICIDE POISONINGS. 4TH ED, P.8 EPA 540/9-88-001. WASHINGTON, DC: U.S. GOVERNMENT PRINTING OFFICE, MARCH 1989]**PEER REVIEWED**

6B. AFTER ASPIRATION OF STOMACH CONTENTS AND LAVAGE, INSTILL ACTIVATED CHARCOAL ... TOGETHER WITH A CATHARTIC IN THE CHARCOAL SLURRY. ADULTS AND CHILDREN OVER 12 YEARS: 50-100 G IN 300-800 ML WATER. CHILDREN UNDER 12: 1.0-1.5 G/KG BODY WEIGHT TO A MAXIMUM OF 50 G PER DOSE. ALTERNATIVE CATHARTICS THAT MAY BE USED INSTEAD ARE SODIUM OR MAGNESIUM SULFATE OR CITRATE: DOSAGE OF SODIUM OR MAGNESIUM SULFATE: ADULTS AND CHILDREN OVER 12 YEARS: 20-30 G. CHILDREN UNDER 12 YEARS: 250 MG/KG BODY WEIGHT. DOSAGE OF MAGNESIUM CITRATE SOLUTION: ADULTS AND CHLIDREN: 4 ML/KG BODY WEIGHT OF PROPRIETARY SOLUTION, UP TO A MAXIMUM OF 300 ML. C. IF GASTRIC ASPIRATION AND LAVAGE IS NOT PERFORMED DUE TO DELAY IN TREATMENT, AND IF PATIENT IS FULLY ALERT, ADMINISTER DOSES OF CHARCOAL AND CATHARTIC ORALLY. WHEN SORBITOL IS GIVEN ORALLY, IT SHOULD BE DILUTED WITH AN EQUAL VOLUME OF WATER TO YIELD A 35% SOLUTION. D. SAVE A SAMPLE OF EMESIS OR INITIAL GASTRIC WASHINGS FOR CHEMICAL ANALYSIS. E. IN SOME CASES OF ORGANOPHOSPHATE INGESTION THERE MAY BE BENEFIT FROM REPEATED ADMINISTRATION OF ACTIVATED CHARCOAL, EITHER BY INGESTION OR STOMACH TUBE ... . /ORGANOPHOSPHATE PESTICIDES/
[MORGAN DP; RECOGNITION AND MANAGEMENT OF PESTICIDE POISONINGS. 4TH ED, P.9 EPA 540/9-88-001. WASHINGTON, DC: U.S. GOVERNMENT PRINTING OFFICE, MARCH 1989]**PEER REVIEWED**

7. OBSERVE PATIENT CLOSELY FOR AT LEAST 72 HOURS (LONGER IN CASES OF ORGANOPHOSPHATE INGESTION) TO INSURE THAT SYMPTOMS (SWEATING, VISUAL DISTURBANCES, VOMITING, DIARRHEA, CHEST AND ABDOMINAL DISTRESS, AND SOMETIMES PULMONARY EDEMA) DO NOT RECUR AS ATROPINIZATION IS WITHDRAWN. IN VERY SEVERE POISONINGS BY INGESTED ORGANOPHOSPHATES, PARTICULARLY THE MORE LIPOPHILIC AND SLOWLY HYDROLYZED COMPOUNDS, METABOLIC DISPOSITION OF TOXICANT MAY REQUIRE AS MANY AS 5-14 DAYS. /ORGANOPHOSPHATE PESTICIDES/
[MORGAN DP; RECOGNITION AND MANAGEMENT OF PESTICIDE POISONINGS. 4TH ED, P.9-10 EPA 540/9-88-001. WASHINGTON, DC: U.S. GOVERNMENT PRINTING OFFICE, MARCH 1989]**PEER REVIEWED**

8. PARTICULARLY IN POISONINGS BY LARGE INGESTED DOSES OF ORGANOPHOSPHATE, MONITOR PULMONARY VENTILATION CAREFULLY, EVEN AFTER RECOVERY FROM MUSCARINIC SYMPTOMATOLOGY, TO FORESTALL RESPIRATORY FAILURE. 9. IN SEVERELY POISONED PATIENTS, MONITOR CARDIAC STATUS BY CONTINUOUS ECG RECORDING. /ORGANOPHOSPHATE PESTICIDES/
[MORGAN DP; RECOGNITION AND MANAGEMENT OF PESTICIDE POISONINGS. 4TH ED, P.10 EPA 540/9-88-001. WASHINGTON, DC: U.S. GOVERNMENT PRINTING OFFICE, MARCH 1989]**PEER REVIEWED**

10. FUROSEMIDE MAY BE CONSIDERED FOR RELIEF OF PULMONARY EDEMA IF RALES PERSIST IN THE LUNGS EVEN AFTER FULL ATROPINIZATION. ... 11. THE FOLLOWING DRUGS ARE PROBABLY CONTRAINDICATED IN NEARLY ALL ORGANOPHOSPHATE POISONING CASES: MORPHINE, THEOPHYLLINE, PHENOTHIAZINES, AND RESERPINE. ADRENERGIC AMINES SHOULD BE GIVEN ONLY IF THERE IS A SPECIFIC INDICATION, SUCH AS MARKED HYPOTENSION. /ORGANOPHOSPHATE PESTICIDES/
[MORGAN DP; RECOGNITION AND MANAGEMENT OF PESTICIDE POISONINGS. 4TH ED, P.10 EPA540/9-88-001. WASHINGTON, DC: U.S. GOVERNMENT PRINTING OFFICE, MARCH 1989]**PEER REVIEWED**

 

Animal Toxicity Studies:

 

 

Evidence for Carcinogenicity:

Evaluation: There is inadequate evidence in humans for the carcinogenicity of dichlorvos. There is sufficient evidence in experimental animals for the carcinogenicity of dichlorvos. Overall evaluation: Dichlorvos is possibly carcinogenic to humans (2B).
[IARC. Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Man. Geneva: World Health Organization, International Agency for Research on Cancer,1972-PRESENT. (Multivolume work).,p. 53 296 (1991)]**PEER REVIEWED**

CLASSIFICATION: B2; probable human carcinogen. BASIS FOR CLASSIFICATION: Significant increases in forestomach tumors in female and male B6C3F1 mice and leukemias and pancreatic acinar adenomas in Fischer 344 rats. Supporting evidence included observation of tumors at other sites in the rat and observation of mutagenicity for both dichlorvos and a major metabolite dichloroacetaldehyde. A structurally related material, dichloropropene , also induces forestomach tumors in rodents. HUMAN CARCINOGENICITY DATA: None. ANIMAL CARCINOGENICITY DATA: Sufficient.
[U.S. Environmental Protection Agency's Integrated Risk Information System (IRIS) on Dichlorvos (62-73-7) Available from: http://www.epa.gov/ngispgm3/iris on the Substance File List as of March 15, 2000]**PEER REVIEWED**

 

Non-Human Toxicity Excerpts:

MUTAGENICITY; MAMMALIAN CYTOGENETICS - IN VIVO BONE MARROW STUDIES, NON-HUMAN: NEGATIVE; MALE GERM CELL STUDIES, NON-HUMAN: NEGATIVE.
[MUTATION RESEARCH 87: 143 (1981)]**PEER REVIEWED**

MUTAGENICITY: DNA REPAIR-DEFICIENT BACTERIAL TESTS: POSITIVE.
[MUTATION RESEARCH 87: 211 (1981)]**PEER REVIEWED**

MUTAGENICITY: ESCHERICHIA COLI WP2,UVRA - REVERSE MUTATION STUDIES: POSITIVE; ESCHERICHIA COLI WP2 - REVERSE MUTATION STUDIES: POSITIVE.
[MUTATION RESEARCH 76: 169 (1980)]**PEER REVIEWED**

MUTAGENICITY: ASPERGILLUS DOMINANT LETHAL MUTATION: POSITIVE; ASPERGILLUS ANEUPLOIDY: POSITIVE; ASPERGILLUS CROSSING OVER: POSITIVE.
[MUTATION RESEARCH 98: 49 (1982)]**PEER REVIEWED**

/IN MALLARDS & PHEASANTS/, THE SYMPTOMOLOGY /(ACUTE ORAL TOXICITY)/ INCLUDED: GOOSE-STEPPING ATAXIA, USE OF WINGS TO AID IN BALANCE, TREMORS, CONVULSIONS. VARIOUS INTERNAL HEMORRHAGES WERE FOUND AT AUTOPSY IN SACRIFICED SURVIVORS OF BOTH SPECIES.
[U. S. Department of the Interior, Fish & Wildlife Service, Bureau of Sport Fisheries & Wildlife. Handbook of Toxicity of Pesticides to Wildlife. Washington, D. C.: U. S. Government PrintingOffice, 1970. 43]**PEER REVIEWED**

... DICHLORVOS ... /WEAKLY/ TERATOGENIC IN SHERMAN STRAIN OF RAT, WHEN ADMIN IP ON DAY 11 OF GESTATION @ DOSE LEVEL WHICH CAUSED SEVERE TOXIC SYMPTOMS IN DAMS. ... DECR FETAL BODY WT WAS MOST SENSITIVE INDICATOR /OF TOXICITY/. ...
[The Chemical Society. Foreign Compound Metabolism in Mammals Volume 3. London: The Chemical Society, 1975. 657]**PEER REVIEWED**

... CHOLINERGIC POISONING ... INCLUDES MUSCULAR FASCICULATIONS, RETCHING, EMESIS, FREQUENT DEFECATION OF WATERY STOOLS, PUPIL CONTRACTION, SECRETION OF TEARS, & LABORED BREATHING ASSOCIATED WITH CONSTRICTION OF BRONCHIOLES.
[Booth, N.H., L.E. McDonald (eds.). Veterinary Pharmacology and Therapeutics. 5th ed. Ames, Iowa: Iowa State University Press, 1982. 832]**PEER REVIEWED**

RATS FED NINETY DAYS ON DIET ... 1000 PPM ... NO SIGNS OF INTOXICATION.
[Worthing, C.R. and S.B. Walker (eds.). The Pesticide Manual - A World Compendium. 8th ed. Thornton Heath, UK: The British Crop Protection Council, 1987. 269]**PEER REVIEWED**

SINGLE ORAL TOXIC DOSE (THAT PRODUCES OBSERVABLE DEVIATION IN ANIMAL'S BEHAVIOR) IS GIVEN ... AS 10 MG/KG ... & 25 MG/KG ... IN CALVES & SHEEP RESPECTIVELY. WHEN APPLIED AS SPRAY TO CATTLE AT CONCN OF 1% HAD NO OBSERVABLE TOXICITY.
[Clarke, M. L., D. G. Harvey and D. J. Humphreys. Veterinary Toxicology. 2nd ed. London: Bailliere Tindall, 1981. 149]**PEER REVIEWED**

DICHLORVOS A 2 YR INHALATION CARCINOGENESIS STUDY IN RATS; SPECIES- CARWORTH FARM E; DEPRESSED GROWTH; INCR SURVIVAL IN RATS EXPOSED TO 5 MG/CU M/2 YR; NO DOSE RELATED INCREASE IN TUMOR RISK.
[BLAIR D ET AL; ARCH TOXICOL 35 (4): 281 (1976)]**PEER REVIEWED**

BIOASSAY FOR CARCINOGENICITY OF TECHNICAL GRADE DICHLORVOS ADMIN IN DIET TO RATS AND MICE FOR 80 WK AT 150 AND 326 PPM (RATS) OR 318 AND 635 PPM (MICE); NO STATISTICALLY SIGNIFICANT INCR IN TUMOR INCIDENCE.
[US NTIS PB REP; ISS PB-270937 (1977)]**PEER REVIEWED**

DICHLORVOS WAS A MUTAGEN IN THE SCREENING TEST FOR MUTAGENICITY USING A REC-ASSAY PROCEDURE, WITH H17 REC(+) AND M45 REC(-) STRAINS OF BACILLUS SUBTILIS AND REVERSION ASSAYS ON AUXOTROPHIC STRAINS OF ESCHERICHIA COLI (WP2) AND SALMONELLA TYPHIMURIUM (AMES SERIES).
[SHIRASU Y ET AL; MUTAT RES 40 (1): 19 (1976)]**PEER REVIEWED**

FEMALE MICE WERE TREATED WITH 25 OR 50 MG/KG ORALLY OR 2 OR 8 UG/L BY INHALATION; NO EFFECT ON % PREGNANT, NUMBER FETAL IMPLANT, OR NUMBER OF EARLY FETAL DEATHS; NO DOMINANT LETHAL MUTATIONS WERE INDUCED AFTER /ORAL/ DOSING WITH HIGH CONCN OF DICHLORVOS.
[EAN BJ, BLIR D; MUTAT RES 40 (1): 67 (1976)]**PEER REVIEWED**

MODERATE NEUROPATHIC RESPONSE WAS OBTAINED IN HENS 2 WK AFTER BEING GIVEN SINGLE MASSIVE SC DOSE OF DICHLORVOS (100 MG/KG OF ACTIVE INGREDIENT IN COMMERCIAL 50% FORMULATION).
[CAROLDI S ET AL; TOXICOL LETT 9 (2): 157 (1981)]**PEER REVIEWED**

INCUBATION OF QUAIL EMBRYOS IN DDVP ENRICHED ATMOSPHERE REVEALS BOTH EMBRYOTOXIC & TERATOGENIC EFFECTS OF THIS PESTICIDE. MULTIPLE MALFORMATIONS ASSOC TO THOSE ASCRIBED TO ANTICHOLINESTERASE ACTION: LORDOSIS, SCOLIOSIS.
[LUTZ-OSTERTTAG Y ET AL; CR SEANCES ACAD SCI (III) 292 (18): 1051 (1981)]**PEER REVIEWED**

Effects of various neuropharmacologic agents on the motility of Dipylidium caninum were studied ... paralytic effects were caused by ... dichlorvos. ...
[Terada M et al; JPN J Pharmacol 32 (3): 479-88 (1982)]**PEER REVIEWED**

Inhalation of dichlorvos at 0.0071 mg/l/hr in rats caused polyuria, dyspnea, paralysis, restlessness, heavy gasping, salivation, and loss of muscular coordination, balance, and body weight, but an increase in lung weight with mild to severe cellular infiltration around the bronchioles causing a mild edema in the lungs.
[Hussain SS et al; Int Pest Cont 24 (3): 64-74 (1982)]**PEER REVIEWED**

/Dichlorvos was/ tested for toxicity and mutagenicity in the forward mutation test system ade6 of the yeast Schizosaccharomyces pombe. Dichlorvos showed a linear dose response relationship for mutagenicity.
[Gilot-Delhalle J et al; Mutat Res 117 (1-2): 139-48 (1983)]**PEER REVIEWED**

The effect of sublethal (1/4th, 1/8th, and 1/16th of 96 hr LC50) of dichlorvos on blood glucose, lactate, and liver and muscle glycogen levels of Clarias batrachus, Saccobranchus fossilis, and Mystus vittatus exposed for 30 days. There was an increase in blood glucose and lactate levels from 10.88 to 36.36% and a decrease in liver and muscle glycogen from 5.19 to 32.19%.
[Verma SR et al; Environ Res 32 (1): 127-133 (1983)]**PEER REVIEWED**

Effects of O,O-dimethyl O-(2,2-dichlorovinyl) phosphate on the brain cholinergic system in Japanese quail /were investigated/. Cholinergic signs, such as salivation and convulsions in legs and wings, were seen 7-15 minutes after administration of DDVP. In the DDVP-treated quail (10 min after dosage of 3 mg/kg), free acetylcholine and labile-bound acetylcholine increased significantly while acetylcholinesterase decreased to 28% of the value determined in untreated quail.
[Kobayashi H et al; Toxicol 28 (3): 219-27 (1983)]**PEER REVIEWED**

MUSCARINIC SIGNS OF /ORGANOPHOSPHORUS CMPD/ ... CONSIST OF HYPERSALIVATION, LACRIMATION, SWEATING & NASAL DISCHARGE. MIOSIS, DYSPNEA, VOMITING, DIARRHEA & FREQUENCY OF URINATION ... NICOTINIC EFFECTS CONSIST OF FASCICULATION OF MUSCLES, WEAKNESS & PARALYSIS. CENTRAL /NERVOUS SYSTEM/ EFFECTS INCLUDE NERVOUSNESS, APPREHENSION, ATAXIA, CONVULSIONS & COMA. DEATH IS DUE TO RESP FAILURE, OR SOMETIMES CARDIAC ARREST. THERE IS LITTLE DIFFERENCE BETWEEN SIGNS PRODUCED BY DIFFERENT ... CMPD, BUT ROUTE OF ABSORPTION MAY INFLUENCE ONE SYSTEM MORE THAN ANOTHER. /ORGANOPHOSPHORUS CMPD/
[Clarke, M. L., D. G. Harvey and D. J. Humphreys. Veterinary Toxicology. 2nd ed. London: Bailliere Tindall, 1981. 153]**PEER REVIEWED**

The effect of dichlorvos on various lipid fractions and lipid peroxidation in the discrete areas of the brain and spinal cord were studied in the fresh water teleost Heteropneustes fossilis exposed to three different doses (3.0, 6.0, and 9.0 ppm) of dichlorvos daily for 7 days. Dose related incr in the levels of total lipids, cholesterol and esterified fatty acids was detected in the fore brain, optic lobes, cerebellum, medulla oblongata and spinal cord. However, phospholipids were significantly decreased in the aforementioned regions of the central nervous system. The rate of lipid peroxidation was significantly increased in all the regions of the central nervous system.
[Vadhva P, Hasan M; J Environ Sci Health B 21 (5): 413-24 (1986)]**PEER REVIEWED**

Clinical and pulmonary function changes induced by iv administration of dichlorvos, the toxicosis and reversibility of these changes after atropine treatment were investigated using six Friesian calves one to three months old. From one minute after dosage, all animals exhibited severe respiratory distress, excitation, weakness, muscle fasciculation and cholinesterase inhibition. Decr in dynamic lung compliance and arterial oxygen tension and incr in total pulmonary resistance, viscous work of breathing and alveolar arterial oxygen gradient were highly significant (p< 0.01). Body secretions, heart rate, respiratory rate, tidal volume and arterial carbon dioxide tension were not significantly affected by dichlorvos injection. Atropine promptly and completely reversed these changes, except for muscle fasciculations, central depression and cholinesterase inhibition which disappeared progressively within 24 hours.
[Lekeux P et al; Res Vet Sci 40 (3): 318-21 (1986)]**PEER REVIEWED**

Three organophosphate compounds, dichlorvos, parathion, and diisopropylfluorophosphate were tested as an unconditioned stimulus in the conditioned taste aversion test. All three compounds caused a dose dependent CTA in rats at doses which did not induce any other signs of toxicity. Experiments with dichlorvos indicated that the minimum dose which caused conditioned taste aversion did not alter the rat's sensitivity to pain or their behavior in either an open field or an inclined plane. Cholinesterase activity was inhibited in a dose dependent manner in brain and plasma after administration of the organophosphates and conditioned taste aversion was correlated with the degree of plasma cholinesterase inhibition. CTA appears to be a sensitive indicator of neurobehavioral effects of mild exposure to organophosphates which causes only 30-40% inhibition of plasma cholinesterase.
[Roney PL et al; Pharmacol Biochem Behav 24 (3): 737-42 (1986)]**PEER REVIEWED**

Alanine aminotransferase and aspartate transferase activities in the liver, brain, and muscle were increased following ip administration of dichlorvos to mice (4 mg/kg/day for 5 days). The incr was the highest in the liver. Dichlorvos also increased the glutamate dehydrogenase activity. The incr was more in the liver than in the muscle and brain.
[Begum SJ et al; Environ Ecol 4 (2): 205-6 (1986)]**PEER REVIEWED**

Snails (Thiara torulosa) were exposed in 2 liter tanks to dichlorvos at concn causing 5 to 95% mortality. Oxygen consumption was measured before and after 24 hr of exposure to the insecticide. At 24, 48, 72, and 96 hr of dichlorvos exposure, the LD50 (mg/ml) and 95% confidence limits, respectively, were as follows: 12.66 (11.44-14.00), 10.69 (9.73-11.75), 9.40 (8.39-10.47), and 8.70 (7.58-10.02). Oxygen consumption values after insecticide exposure showed a significant incr at sublethal concn, but decr at concn > LC50.
[Bharathi C, Prasada Rao DGV; Bull Environ Contam Toxicol 42 (5): 773-7 (1989)]**PEER REVIEWED**

Three of 12 dogs given 22 mg/kg of dichlorvos orally died. The effect of dichlorvos on plasma and erythrocyte cholinesterase activity in the dog and the rate at which these subsequently return to normal have been studied ... . No adverse effects, other than a reversible erythema and loss of hair in one animal, were produced in dogs wearing plastic collars, containing dichlorvos. ... Dogs wearing either collars impregnated with 9.3% of dichlorvos or medallions containing 18.3% of this material were unaffected, whereas those wearing collars, with 16.5% of dichlorvos plus 1% chlorpyrifos developed characteristic skin lesions after four weeks.
[Humphreys, D.J. Veterinary Toxicology. 3rd ed. London, England: Bailliere Tindell, 1988. 163]**PEER REVIEWED**

Horses: Signs of intoxication developed in two of four foals given 50 mg/kg body weight of dichlorvos orally, whereas all the animals given twice this level or more were affected.
[Humphreys, D.J. Veterinary Toxicology. 3rd ed. London, England: Bailliere Tindell, 1988. 162]**PEER REVIEWED**

Administration of dichlorvos does not result in residues in the tissues or the eggs of poultry. Suspected malicious dichlorvos poisoning which resulted in the death of 27,000 one month old chickens has been described ... . Dichlorvos can cause decreased hatchability and laying capacity and an increase in the number of abnormal chicks in pheasants.
[Humphreys, D.J. Veterinary Toxicology. 3rd ed. London, England: Bailliere Tindell, 1988. 163]**PEER REVIEWED**

Cats wearing dichlorvos impregnated collars in a warm, dry atmosphere have developed clinical signs including an ataxia depression syndrome and cervical contact dermatitis. Many of the severely affected cats were anemic and some animals died. Cats wearing three impregnated collars developed classical acute organophosphorus compound poisoning. Although some initial and transient inhibition of whole blood and tissue cholinesterase activity can occur, the wearing of a single flea control collar should not produce any untoward effects in cats.
[Humphreys, D.J. Veterinary Toxicology. 3rd ed. London, England: Bailliere Tindell, 1988. 163]**PEER REVIEWED**

Application of dichlorvos to cattle does not result in residues in the tissue or milk. The minimum toxic concentration of dichlorvos in spray form to baby calves 0.05-0.1%, and the lethal concentration 0.25%.
[Humphreys, D.J. Veterinary Toxicology. 3rd ed. London, England: Bailliere Tindell, 1988. 162]**PEER REVIEWED**

Recovery of plasma and erythrocyte cholinesterase is slow in pigs treated with dichlorvos. The piglets of dichlorvos treated gilts have a higher liver glycogen level and show a slower increase in body weight during the first 72 hours of age than the piglets of untreated gilts. Dichlorvos does not have any teratogenic effect in the pig. No intact dichlorvos is found in the blood or tissues of treated pigs.
[Humphreys, D.J. Veterinary Toxicology. 3rd ed. London, England: Bailliere Tindell, 1988. 162]**PEER REVIEWED**

The question has remained open, whether or not the pesticide dichlorvos (DDVP) should be classified as a carcinogen. The results of a long term experiment of testing DDVP in male and female C57B1/6/B1n mice ... did not indicate the development of neoplastic lesions due to the administration of the compound. /Results of a/ long term administration of DDVP to male and female BD IX/Bln rats /has been reported/. In the groups of male rats a increased incidence of proliferations of bile duct cells and of oval cells of the liver was observed, which was statistically significant (p< 0.05) in the group of the higher dosed animals when compared with the group of the vehicle control male rats. Among the DDVP treated female rats a significantly decreased incidence of tumors of the adrenal glands and of mammary tumors was observed as compared to the vehicle control group. Similar results were obtained in earlier experiments, when rats were treated with Trichlorofon, which easily converts to DDVP. In comparison to the corresponding control group DDVP treated male rats showed a higher incidence of focal, hyperplasias of the urinary bladder, of focal hyperplasias of the pelvis and of transitional cell carcinomas of the renal pelvis. DDVP treated female rats showed the opposite, namely lower incidences of these types of tumors, when compared with the control group. In our study on rats there were no neoplastic lesions found which could be attributed to the treatment of the animals with DDVP.
[Horn KH et al; Arch Geschwulstforsch 58 (1): 1-10 (1988)]**PEER REVIEWED**

Up to now the question remained open, whether or not the pesticide dichlorvos, should be classified as a carcinogen. /Results of a/ long time oral administration /study/ to male and female C57B1/6/B1n mice of dichlorovos to test the compound for carcinogenic activity /has been reported/. Dichlorvos significantly increased the incidence of focal hyperplasias (transitional cell hyperplasias) of the urinary bladder in male and female mice and decreased significantly the incidence of mixed lymphomas in mice of both sexes as compared with control animals (treated with solvent or untreated). There were no neoplastic lesions found including papillomas of the urinary bladder which could be attributed to the treatment of the animals with dichlorvos.
[Horn KH et al; Arch Geschwulstforsch 57 (5): 353-60 (1987)]**PEER REVIEWED**

The induction of chromosomal aberrations by insecticides was studied in hamsters. Female Syrian golden hamsters were injected ip with a median lethal dose (LD50), 0.5 LD50, 0.25 LD50, or 0.1 LD50 of demeton, dimethoate, dichlorvos, endosulfan, trichlorofon, a carbaryl and lindane mixture, a methoxychlor and propoxur mixture, malathion, or 40 mg/kg cyclophosphamide, the positive control. After 22 hours, animals were injected with 0.8% colchicine. After 24 hours, bone marrow was isolated, chromosome preparations were made, and the average mitotic index was calculated. At least 50 metaphases obtained from bone marrow of each animal were analyzed. The activity of the insecticides was compared with those of positive and negative controls. Cyclophosphamide induced aberrations in 9% of the analyzed cells, significantly higher than 1.3% in the negative controls. Chromosomal aberrations increased after insecticide administration. The most commonly observed abnormalities were gaps and breaks, mainly chromatid type, and some single dicentric and ring chromosomes. Demeton, dichlorvos, endosulfan, propoxur mixture, malathion, and dimethoate caused statistically significant increases in aberrant cells. Dimethoate was weakly clastogenic. Demeton was clastogenic in the three highest doses used. Aberrant cells observed after administration of the highest doses of dichlorvos and endosulfan did not differ from those of the positive control. Statistically significant increases in aberrant cells after some doses of malathion and propoxur mixture indicated that these compounds were potential carcinogens. Lindane mixture and trichlorfon did not induce chromosomal aberrations. It was concluded that dichlorvos, demeton, dimethoate, and malathion induce chromosomal aberrations in the bone marrow of Syrian hamsters.
[Dzwonkowska A, Hubner H; Arch Toxicol 58 (3): 152-6 (1986)]**PEER REVIEWED**

The efficacy of a leukemia cell transplant model to measure potential chemotherapeutic activity was tested with five different chemicals that had previously been evaluated in 2 year studies. Leukemic spleen cells from Fischer rats were injected subcutaneously into syngeneic recipients and the effects of chemical treatment on tumor progression were evaluated at 70 days post transplant. The data from the short term assay were in all cases correlated with the trends reported for mononuclear cell leukemia in 2 year studies, where two chemicals were reported to decease the incidence and three chemicals were reported to increase the incidence of leukemia. Short term treatment with the two chemicals which caused negative trends for leukemia (2-ethoxyethanol or ethylene glycol monoethyl ether; 4-hexylresorcinol) delayed and/or reduced tumor growth in the transplant model in a dose related fashion, as exhibited by reduction or elimination of splenomegaly and leukoblastosis, and a reversal in the depression of red blood cell indices or platelet counts. By contrast, the rate of tumor progression was increased in the short term assay of the three chemicals which previously caused increased trends for leukemia in 2 year studies (pyridine; 2,4,6-trichlorophenol, dichlorvos). The severity of the mononuclear cell leukemia in the transplant recipients, as measured by histopathological examination of spleen and liver, was correlated with the changes in tumor growth rates. The in vivo leukemia transplant model is a short term assay that could be used to screen a variety of potential chemotherapeutic agents, or to study structure activity relationships within one class of chemicals.
[Dieter MP et al; Leuk Res 13 (9): 841-9 (1989)]**PEER REVIEWED**

The neurotoxic effect on the central and peripheral nervous system of dichlorvos (DDVP) was investigated by a computer system in acute and subchronic experiments in CFY male rats. The administered peroral doses were given by gavage; the acute group was given a single 88 mg/kg dose and the 2 subchronic groups were given 1.6 mg/kg or 0.8 mg/kg daily for a period of 6 weeks. Significant changes of the function of CNS, increase of EEG mean frequency, decrease of EEG amplitude, that of activity of EEG bands (power density), and peripheral nervous system, decrease of conduction velocity, increase of relative and absolute refractory periods, were found after treatment with both the single large and repeated small doses of dichlorvos. There were no correlations between the functional disturbances of the central and peripheral nervous systems and the inhibition of the cholinesterase activity in various organs and the blood.
[D'esi I, Nagymajt'enyi L; Toxicol 49 (1): 141-8 (1988)]**PEER REVIEWED**

The organophosphate pesticide, dichlorvos (DDVP), is used commonly to control ectoparasites in laboratory rodent colonies. This compound is relatively nontoxic to Mus musculus at dosages several times the therapeutic level. However, usage of a similar therapeutic level in the white-footed mouse (Peromyscus leucopus) resulted in substantial mortality. To determine whether Peromyscus leucopus is more susceptible than Mus musculus to the toxic effects of DDVP, both species were exposed to 0, 3 and 6 g of pelleted DDVP per cage. In a subsequent experiment, Peromyscus leucopus were exposed to 0 and 1 g of DDVP per cage. Mortality was not observed in Mus musculus at any dosage level. Peromyscus leucopus exposed to 1, 3 and 6 g of DDVP exhibited mortalities of 3%, 20% and 53%, respectively. Mean serum cholinesterase in Peromyscus leucopus exposed to 3 and 6 g of DDVP was 0.35 and 0.21 U/ml as compared to 3.13 U/ml in unexposed mice. The analogous values for Mus musculus were 1.60 and 0.79 U/ml while the level in unexposed mice was 6.79 U/ml. In the second experiment, mean serum cholinesterase in Peromyscus leucopus exposed to 1 g of DDVP was 0.32 U/ml as compared to 2.33 U/ml in unexposed mice. Histopathology revealed no lesions in the brain, liver or kidneys. The increased susceptibility of Peromyscus leucopus to the toxic effects of DDVP was related to the lowered serum cholinesterase. This indicates that DDVP should not be used for control of ectoparasites in Peromyscus leucopus.
[Di Giacomo RF et al; Lab Anim Sci 37 (4): 471-3 (1987)]**PEER REVIEWED**

Dichlorvos (dichlorovinyl dimethyl phosphoric acid ester) is a cholinesterase inhibitor used widely as a contact and stomach insecticide for control of internal and external parasites. Carcinogenesis studies were conducted by administering dichlorvos in corn oil by gavage 5 times a week for 103 weeks to groups of 50 male and 50 female Fischer rats at 0, 4, or 8 mg/kg body weight, to groups of 50 male B6C3F1 mice at 0, 10, or 20 mg/kg, and to groups of 50 female B6C3F1 mice at 0, 20, or 40 mg/kg. During the course of the studies, body weights and survival rates of the male and female rats and mice were not different from those of their respective controls; females of both species appeared to gain more weight than controls. Neoplasms induced by dichlorovos included adenomas of the exocrine pancreas (male rats), mononuclear cell leukemia (male rats), and squamous cell papilloma of the forestomach (male and female mice; two other female mice had squamous cell carcinomas). Lesions observed in female rats that may have been due to dichlorvos administration included adenomas of the exocrine pancreas and fibroadenomas of the mammary gland. The results demonstrated that dichlorvos is carcinogenic for Fischer rats and B6C3F1 mice.
[Chan PC et al; Jpn J Cancer Res 82 (20: 157-64 (1991)]**PEER REVIEWED**

To test whether exposure to dichlorvos vapors for treatment of mouse ectoparasites resulted in temporary cessation of breeding, we exposed harem breeding groups of mice to varying concentrations of dichlorvos vapors and examined the effects of exposure on litter frequency and litter size. All exposure levels resulted in decreased plasma cholinesterase concentrations in treated mice for up to 10 days following the completion of exposure. Litter freqency and size were unaffected by dichlorvous exposure, and gestation times were not prolonged. Therefore, treatment with dichlorvos vapors during breeding did not affect reproduction in exposed mice.
[Casebolt DB et al; Lab Anim Sci 40 (1): 65-7 (1990)]**PEER REVIEWED**

 

National Toxicology Program Studies:

Two yr studies of dichlorvos were conducted by admin 0, 4, or 8 mg/kg dichlorvos 5 days/wk for 103 wk, to groups of 50 F344/N rats of each sex. Groups of 50 male B6C3F1 mice were admin 0, 10, or 20 mg/kg dichlorvos on the same schedule, and groups of 50 B6C3F1 female mice were admin 0, 20, or 40 mg/kg dichlorvos. Body Weight and Survival in the Two Year Studies: Mean body weights of dosed and vehicle control rats and mice were similar. No significant differences in survival were observed between any groups of rats or mice of either sex (Rats male: vehicle control, 31/50; low dose, 25/50; high dose, 24/50; Rats female: 31/50; 26/50; 26/50; Mice male: 35/50; 27/50; 29/50; Mice female: 26/50; 29/50; 34/50). Neoplastic Effects in the Two Year Studies: Adenomas of the exocrine pancreas occurred at greater incidence in dosed rats than in vehicle controls (male: vehicle control, 25/50; low dose, 30/49; high dose 33/50; female: 2/50; 3/47; 6/50). Mononuclear cell leukemia in both dosed groups of male rats occurred more frequently than in vehicle controls (11/50; 20/50; 21/50). Mammary gland fibroadenomas and fibroadenomas or adenomas (combined) in dosed female rats occurred at incr incidence relative to the vehicle controls (9/50; 19/50; 17/50). Multiple fibroadenomas occurred in dosed female rats but not in vehicle controls (0/50; 6/50; 3/50); carcinomas occurred in two vehicle control and two low dose female rats. In mice, incidence of squamous cell papillomas of the forestomach was incr in the high dose groups compared with those in the vehicle controls (1/50; 1/50; 5/50; female: 5/49; 6/49; 18/50). Two high dose female mice developed forestomach carcinomas. Conclusions: Under the conditions of these 2 yr gavage studies, there was some evidence of the carcinogenic activity of dichlorvos for male F344/N rats as shown by incr incidence of adenomas in the exocrine pancreas and mononuclear cell leukemia. There was equivocal evidence of carcinogenic activity of dichlorvos in female F344/N rats as shown by incr incidence of adenomas of the exocrine pancreas and mammary gland fibroadenomas. There was some evidence of the carcinogenic activity of dichlorvos for male B6C3F1 mice as shown by incr incidence of forestomach squamous cell papillomas. There was clear evidence of carcinogenic activity of dichlorvos for female B6C3F1 mice as shown by incr incidence of forestomach squamous cell papillomas.
[DHHS/NTP; Toxicology & Carcinogenesis Studies of Dichlorvos in F344/N Rats and B6C3F1 Mice (Gavage Studies) Technical Report Series No. 342 (1989) NIH Publication No. 89-2598]**PEER REVIEWED**

A bioassay for the possible carcinogenicity of technical grade dichlorvos was conducted using Osborne-Mendel rats and B6C3F1 mice. The test material was admin in the diet at two concn for 80 wk to groups of 50 animals of each species and sex. The test animals were held for observation, and surviving rats were /sacrificed/ at 110-111 wk and surviving mice at 92-94 wk from the initiation of the study. Initial doses in both species were not well tolerated and they were lowered after a few wk. Time weighted avg doses for both males and females were 150 and 326 ppm for the rats and 318 and 635 ppm for mice. The matched controls consisted of 60 rats of each sex, 100 male mice, and 80 female mice. All surviving rats were /sacrificed/ at 106 to 109 wk; surviving mice at 92-94 wk. After the doses were reduced, no toxic signs directly attributable to the cmpd were observed. However, avg weights of high dose animals were slightly depressed. Survival was not dose related in either species. Microscopic study of the tissues of treated animals and matched and pooled controls revealed no statistically significant incr in the incidence of tumors attributable to exposure to dichlorvos in either animal species. The significance of the three esophageal tumors in male and female mice and of malignant fibrous histiocytomas in male mice is unclear and there is insufficient evidence to indicate they were associated with dichlorvos treatment. Thus under the conditions of this study, dichlorvos was not demonstrated to be carcinogenic. Levels of Evidence of Carcinogenicity: Male Rats: Negative; Female Rats: Negative; Male Mice: Negative; Female Mice: Negative.
[DHEW/NCI; Bioassay of Dichlorvos for Possible Carcinogenicity. Technical Rpt No. 10 (1977)]**PEER REVIEWED**

 

Non-Human Toxicity Values:

LD50 Rat acute oral 56 to 80 mg/kg.
[Matsumura, F. Toxicology of Insecticides. 2nd ed. New York, NY: Plenum Press, 1985. 75]**PEER REVIEWED**

LD100 Dog 30 mg/kg in 27 minutes
[Cordoba D et al; Vet Hum Toxicol 25 (1): 1-3 (1983)]**PEER REVIEWED**

LD50 Rat oral 17 mg/kg
[Lewis, R.J. Sax's Dangerous Properties of Industrial Materials. 9th ed. Volumes 1-3. New York, NY: Van Nostrand Reinhold, 1996. 1132]**PEER REVIEWED**

LC50 Rat ihl 15 mg/cu m/4 hr
[Lewis, R.J. Sax's Dangerous Properties of Industrial Materials. 9th ed. Volumes 1-3. New York, NY: Van Nostrand Reinhold, 1996. 1132]**PEER REVIEWED**

LD50 Rat skin 70,400 ug/kg
[Lewis, R.J. Sax's Dangerous Properties of Industrial Materials. 9th ed. Volumes 1-3. New York, NY: Van Nostrand Reinhold, 1996. 1132]**PEER REVIEWED**

LD50 Rat ip 23,300 ug/kg
[Lewis, R.J. Sax's Dangerous Properties of Industrial Materials. 9th ed. Volumes 1-3. New York, NY: Van Nostrand Reinhold, 1996. 1132]**PEER REVIEWED**

LD50 Rat sc 10,800 ug/kg
[Lewis, R.J. Sax's Dangerous Properties of Industrial Materials. 9th ed. Volumes 1-3. New York, NY: Van Nostrand Reinhold, 1996. 1132]**PEER REVIEWED**

LD50 Mouse oral 61 mg/kg
[Lewis, R.J. Sax's Dangerous Properties of Industrial Materials. 9th ed. Volumes 1-3. New York, NY: Van Nostrand Reinhold, 1996. 1132]**PEER REVIEWED**

LC50 Mouse ihl 13 mg/cu m/4 hr
[Lewis, R.J. Sax's Dangerous Properties of Industrial Materials. 9th ed. Volumes 1-3. New York, NY: Van Nostrand Reinhold, 1996. 1132]**PEER REVIEWED**

LD50 Mouse skin 206 mg/kg
[Lewis, R.J. Sax's Dangerous Properties of Industrial Materials. 9th ed. Volumes 1-3. New York, NY: Van Nostrand Reinhold, 1996. 1132]**PEER REVIEWED**

LD50 Mouse ip 22 mg/kg
[Lewis, R.J. Sax's Dangerous Properties of Industrial Materials. 9th ed. Volumes 1-3. New York, NY: Van Nostrand Reinhold, 1996. 1132]**PEER REVIEWED**

LD50 Rabbit skin 107 mg/kg
[Lewis, R.J. Sax's Dangerous Properties of Industrial Materials. 9th ed. Volumes 1-3. New York, NY: Van Nostrand Reinhold, 1996. 1132]**PEER REVIEWED**

LD50 Rabbit oral 10 mg/kg
[Lewis, R.J. Sax's Dangerous Properties of Industrial Materials. 9th ed. Volumes 1-3. New York, NY: Van Nostrand Reinhold, 1996. 1132]**PEER REVIEWED**

LD50 Dog oral 100 mg/kg
[Lewis, R.J. Sax's Dangerous Properties of Industrial Materials. 9th ed. Volumes 1-3. New York, NY: Van Nostrand Reinhold, 1996. 1132]**PEER REVIEWED**

LD50 Mouse iv 18 mg/kg
[Lewis, R.J. Sax's Dangerous Properties of Industrial Materials. 9th ed. Volumes 1-3. New York, NY: Van Nostrand Reinhold, 1996. 1132]**PEER REVIEWED**

LD50 Mouse sc 24 mg/kg
[Lewis, R.J. Sax's Dangerous Properties of Industrial Materials. 9th ed. Volumes 1-3. New York, NY: Van Nostrand Reinhold, 1996. 1132]**PEER REVIEWED**

LD50 Rat male oral 80 mg/kg
[Clayton, G.D., F.E. Clayton (eds.) Patty's Industrial Hygiene and Toxicology. Volumes 2A, 2B, 2C, 2D, 2E, 2F: Toxicology. 4th ed. New York, NY: John Wiley & Sons Inc., 1993-1994. 723]**PEER REVIEWED**

LD50 Rat female oral 55 mg/kg
[Clayton, G.D., F.E. Clayton (eds.) Patty's Industrial Hygiene and Toxicology. Volumes 2A, 2B, 2C, 2D, 2E, 2F: Toxicology. 4th ed. New York, NY: John Wiley & Sons Inc., 1993-1994. 723]**PEER REVIEWED**

LD50 Rat male dermal 107 mg/kg
[Clayton, G.D., F.E. Clayton (eds.) Patty's Industrial Hygiene and Toxicology. Volumes 2A, 2B, 2C, 2D, 2E, 2F: Toxicology. 4th ed. New York, NY: John Wiley & Sons Inc., 1993-1994. 723]**PEER REVIEWED**

LD50 Rat female dermal 75 mg/kg
[Clayton, G.D., F.E. Clayton (eds.) Patty's Industrial Hygiene and Toxicology. Volumes 2A, 2B, 2C, 2D, 2E, 2F: Toxicology. 4th ed. New York, NY: John Wiley & Sons Inc., 1993-1994. 723]**PEER REVIEWED**

 

Ecotoxicity Values:

LC50 FATHEAD MINNOW 11,600 UG/L/96 HR @ 17 DEG C (95% CONFIDENCE LIMIT 7,830-17,200 UG/L) WT 0.7 G IN A STATIC BIOASSAY /TECHNICAL MATERIAL, 93%/
[U.S. Department of Interior, Fish and Wildlife Service. Handbook of Acute Toxicity of Chemicals to Fish and Aquatic Invertebrates. Resource Publication No. 137. Washington, DC: U.S. Government PrintingOffice, 1980. 28]**PEER REVIEWED**

LC50 BLUEGILL 869 UG/L/96 HR @ 18 DEG C (95% CONFIDENCE LIMIT 700-1,080 UG/L), WT 1.5 G IN A STATIC BIOASSAY /TECHNICAL MATERIAL, 100%/
[U.S. Department of Interior, Fish and Wildlife Service. Handbook of Acute Toxicity of Chemicals to Fish and Aquatic Invertebrates. Resource Publication No. 137. Washington, DC: U.S. Government PrintingOffice, 1980. 28]**PEER REVIEWED**

LC50 MOSQUITOFISH 5,270 UG/L/96 HR @ 17 DEG C (95% CONFIDENCE LIMIT 2,660-10,400 UG/L), WT 0.2 G IN A STATIC BIOASSAY /TECHNICAL MATERIAL, 100%/
[U.S. Department of Interior, Fish and Wildlife Service. Handbook of Acute Toxicity of Chemicals to Fish and Aquatic Invertebrates. Resource Publication No. 137. Washington, DC: U.S. Government PrintingOffice, 1980. 28]**PEER REVIEWED**

LC50 CUTTHROAT TROUT 170 UG/L/96 HR @ 12 DEG C (95% CONFIDENCE LIMIT 143-203 UG/L), WT 2.5 G IN A STATIC BIOASSAY /TECHNICAL MATERIAL, 100%/
[U.S. Department of Interior, Fish and Wildlife Service. Handbook of Acute Toxicity of Chemicals to Fish and Aquatic Invertebrates. Resource Publication No. 137. Washington, DC: U.S. Government PrintingOffice, 1980. 28]**PEER REVIEWED**

LC50 PTERONARCYS 0.10 UG/L/96 HR @ 15 DEG C (95% CONFIDENCE LIMIT 0.07-0.15 UG/L), 2ND YR CLASS IN A STATIC BIOASSAY /TECHNICAL MATERIAL 100%/
[U.S. Department of Interior, Fish and Wildlife Service. Handbook of Acute Toxicity of Chemicals to Fish and Aquatic Invertebrates. Resource Publication No. 137. Washington, DC: U.S. Government PrintingOffice, 1980. 28]**PEER REVIEWED**

LC50 GAMMARUS LACUSTRIS 0.50 UG/L/96 HR @ 21 DEG C (95% CONFIDENCE LIMIT 0.37-0.68 UG/L), MATURE IN A STATIC BIOASSAY /TECHNICAL MATERIAL, 100%/
[U.S. Department of Interior, Fish and Wildlife Service. Handbook of Acute Toxicity of Chemicals to Fish and Aquatic Invertebrates. Resource Publication No. 137. Washington, DC: U.S. Government PrintingOffice, 1980. 28]**PEER REVIEWED**

LC50 Gammarus faciatus 0.40 ug/l/96 hr /Conditions of bioassay not specified/
[Verschueren, K. Handbook of Environmental Data of Organic Chemicals. 2nd ed. New York, NY: Van Nostrand Reinhold Co., 1983. 510]**PEER REVIEWED**

LC50 Crangon septemspinosa (sand shrimp) 4 ppb/96 hr in a static bioassay
[Verschueren, K. Handbook of Environmental Data of Organic Chemicals. 2nd ed. New York, NY: Van Nostrand Reinhold Co., 1983. 510]**PEER REVIEWED**

LC50 Palaemonetes vulgaris (grass shrimp) 15 ppb/96 hr in a static bioassay
[Verschueren, K. Handbook of Environmental Data of Organic Chemicals. 2nd ed. New York, NY: Van Nostrand Reinhold Co., 1983. 510]**PEER REVIEWED**

LC50 Pagurus longicarpus (hermit crab) 45 ppb/96 hr in a static bioassay
[Verschueren, K. Handbook of Environmental Data of Organic Chemicals. 2nd ed. New York, NY: Van Nostrand Reinhold Co., 1983. 510]**PEER REVIEWED**

LC50 Bluegill 1000 ppm/24 hr /Conditions of bioassay not specified/
[Verschueren, K. Handbook of Environmental Data of Organic Chemicals. 2nd ed. New York, NY: Van Nostrand Reinhold Co., 1983. 510]**PEER REVIEWED**

LC50 Fundulus heteroclitus (mummichog) 2680 ppb/96 hr in a static bioassay
[Verschueren, K. Handbook of Environmental Data of Organic Chemicals. 2nd ed. New York, NY: Van Nostrand Reinhold Co., 1983. 511]**PEER REVIEWED**

LC50 Fundulus majalis (striped killifish) 2300 ppb/96 hr in a static bioassay
[Verschueren, K. Handbook of Environmental Data of Organic Chemicals. 2nd ed. New York, NY: Van Nostrand Reinhold Co., 1983. 511]**PEER REVIEWED**

LC50 Menidia menidia (Atlantic silverside) 1250 ppb/96 hr in a static lab bioassay
[Verschueren, K. Handbook of Environmental Data of Organic Chemicals. 2nd ed. New York, NY: Van Nostrand Reinhold Co., 1983. 511]**PEER REVIEWED**

LC50 Mugil cephalus (striped mullet) 200 ppb/96 hr in a static lab bioassay
[Verschueren, K. Handbook of Environmental Data of Organic Chemicals. 2nd ed. New York, NY: Van Nostrand Reinhold Co., 1983. 511]**PEER REVIEWED**

LC50 Anguilla rostrata (American eel) 1800 ppb/96 hr static lab bioassay
[Verschueren, K. Handbook of Environmental Data of Organic Chemicals. 2nd ed. New York, NY: Van Nostrand Reinhold Co., 1983. 511]**PEER REVIEWED**

LC50 Thalassoma bifasciatum (bluehead) 1440 ppb/96 hr in a static lab bioassay
[Verschueren, K. Handbook of Environmental Data of Organic Chemicals. 2nd ed. New York, NY: Van Nostrand Reinhold Co., 1983. 511]**PEER REVIEWED**

LC50 Sphaeroides maculatus (Northern puffer) 2250 ppb/96 hr in a static lab bioassay
[Verschueren, K. Handbook of Environmental Data of Organic Chemicals. 2nd ed. New York, NY: Van Nostrand Reinhold Co., 1983. 511]**PEER REVIEWED**

LC50 Coturnix japonica (Japanese quail) oral 265 ppm
[Hill, E.F. and Camardese, M.B. Lethal Dietary Toxicities of Environmental Contaminants and Pesticides to Coturnix. Fish and Wildlife Technical Report 2.Washington, DC: United States Department of Interior Fish and Wildlife Service, 1986. 57]**PEER REVIEWED**

LD50 Thiara torulosa 12.66 and 11.44-14.00, 10.69 and 9.73-11.75, 9.40 and 8.39-10.47, and 8.70 and 7.58-10.02 mg/l at 95% confidence limits of 24, 48, 72, and 96 hr, respectively.
[Bharathi C, Prasada Rao DGV; Bull Environ Contam Toxicol 42 (5): 773-7 (1989)]**PEER REVIEWED**

 

Metabolism/Pharmacokinetics:

 

 

Metabolism/Metabolites:

VINYL-1-(14)CARBON- & (36)CLORIDE -DICHLORVOS WAS ADMIN ORALLY TO ... RATS. ... METABOLITE FROM VINYL CARBONS WAS CO2. URINE ANALYSES ... HIPPURIC ACID (8.3%), 2,2-DICHLOROVINYL METHYL PHOSPHATE (10.9%), 2,2-DICHLOROETHYL-BETA-D-GLUCOPYRANOSIDURONIC ACID (27%), & UREA (3.1%).
[Menzie, C. M. Metabolism of Pesticides, An Update. U.S. Department of the Interior, Fish, Wild-life Service, Special Scientific Report - Wildlife No. 184, Washington, DC: U.S. GovernmentPrinting Office, l974. 150]**PEER REVIEWED**

IN RATS ... DEGRADED BY TWO ENZYMATIC PATHWAYS. ... GLUTATHIONE DEPENDENT, PROCEEDS VIA DEMETHYLATION TO DESMETHYL DDVP. ... NOT DEPENDENT UPON GLUTATHIONE ... VIA HYDROLYSIS TO DIMETHYL PHOSPHATE & DICHLOROACETALDEHYDE. DESMETHYL DDVP METABOLISM TO MONOMETHYL PHOSPHATE & DICHLOROACETALDEHYDE WAS GLUTATHIONE-INDEPENDENT ALSO.
[Menzie, C. M. Metabolism of Pesticides, An Update. U.S. Department of the Interior, Fish, Wild-life Service, Special Scientific Report - Wildlife No. 184, Washington, DC: U.S. GovernmentPrinting Office, l974. 150]**PEER REVIEWED**

USING WHOLE HOMOGENATES OF RAT & RABBIT TISSUES ... METABOLISM OF DDVP-(32)PHOSPHORUS WAS FOLLOWED. IN LIVER, KIDNEY, SPLEEN, & ADRENAL GLANDS, PRINCIPAL METABOLITE WAS DIMETHYL PHOSPHATE (50-85%). REMAINDER APPEARED AS O-METHYL 2,2-DICHLOROVINYL PHOSPHATE, MONOMETHYL PHOSPHATE, & INORGANIC PHOSPHATE.
[Menzie, C.M. Metabolism of Pesticides. U.S. Department of the Interior, Bureau of Sport Fisheries and Wildlife, Publication 127. Washington, DC: U.S. Government Printing Office, 1969. 136]**PEER REVIEWED**

MAJOR PROPORTION OF DICHLOROACETALDEHYDE OBTAINED FROM VINYL LINKAGE CLEAVAGE APPEARS TO BE REDUCED TO DICHLOROETHANOL WITH VERY SMALL AMT GOING TO DICHLOROACETIC ACID.
[White-Stevens, R. (ed.). Pesticides in the Environment: Volume 1, Part 1, Part 2. New York: Marcel Dekker, Inc., 1971. 177]**PEER REVIEWED**

... BLUEGILL ... & CHANNEL CATFISH ... /EXPOSED TO DDVP/ CHROMATOGRAPHY REVEALED PRESENCE OF DIMETHYLPHOSPHATE & DICHLOROACETALDEHYDE.
[Menzie, C.M. Metabolism of Pesticides. U.S. Department of the Interior, Bureau of Sport Fisheries and Wildlife, Publication 127. Washington, DC: U.S. Government Printing Office, 1969. 136]**PEER REVIEWED**

WHEN APPLIED TO STORED WHEAT, DDVP UNDERWENT RAPID DEGRADATION TO DIMETHYL PHOSPHATE & PHOSPHORYLATED PROTEIN DERIVATIVES.
[Menzie, C. M. Metabolism of Pesticides, An Update. U.S. Department of the Interior, Fish, Wild-life Service, Special Scientific Report - Wildlife No. 184, Washington, DC: U.S. GovernmentPrinting Office, l974. 150]**PEER REVIEWED**

AFTER ADMIN OF DDVP TO YOUNG PIGS, ANALYSES SHOWED PRESENCE OF DIMETHYL DDVP, DICHLOROACETALDEHYDE, DICHLOROETHANOL, & DICHLOROACETIC ACID IN INTESTINAL LUMEN BUT ONLY DICHLOROETHANOL IN PORTAL OR PERIPHERAL BLOOD.
[Menzie, C. M. Metabolism of Pesticides, An Update. U.S. Department of the Interior, Fish, Wild-life Service, Special Scientific Report - Wildlife No. 184, Washington, DC: U.S. GovernmentPrinting Office, l974. 150]**PEER REVIEWED**

Dichlorvos (DDVP) is a methylating agent. DNA from mice given 1.9E-6 mol/kg of DDVP, degree of alkylation of guanine-n-7 accounting to 8E-13 mol methyl per gram of DNA was found. Rate of clearance was (estimated) to be 29 hr .
[Segerback D, Ehenberg L; Acta Pharmacol Toxicol 49 (Suppl 5): 56-66 (1981)]**PEER REVIEWED**

Dichlorvos, one of the active metabolites of trichlorofon ... is hydrolyzed to give dimethyl phosphate and dichloroacetaldehyde. The latter is subsequently reduced to beta,beta-dichloroethyl alcohol, characteristically converted by rats when administered intraperitoneally. After hydrolysis to a two-carbon fragment, dichloroacetaldhyde is able to enter a pathway of intermediary metabolism, and carbon dioxide is the major radioactive metabolic.
[Aizawa, H. Metabolic Maps of Pesticides. New York, NY: Academic Press, 1982. 154]**PEER REVIEWED**

IN VITRO STUDIES WITH SERUM INDICATED SMALL AMT OF DESMETHYL DDVP BUT LARGE AMT OF DIMETHYLPHOSPHATE.
[Menzie, C.M. Metabolism of Pesticides. U.S. Department of the Interior, Bureau of Sport Fisheries and Wildlife, Publication 127. Washington, DC: U.S. Government Printing Office, 1969. 136]**PEER REVIEWED**

 

Absorption, Distribution & Excretion:

(14)CARBON DICHLORVOS WAS RAPIDLY BIOTRANSFORMED AFTER ORAL ADMIN TO RATS. 38% OF (14)CARBON WAS EXCRETED IN EXPIRED AIR, 16% IN URINE, & 4% IN FECES IN 4 DAYS. RETAINED (14)CARBON REPRESENTED MATERIAL INCORPORATED INTO PATHWAYS OF INTERMEDIARY METABOLISM. SIMILAR EXCRETION-RETENTION DATA WERE OBTAINED AFTER INHALATION ...
[The Chemical Society. Foreign Compound Metabolism in Mammals. Volume 2: A Review of the Literature Published Between 1970 and 1971. London: The Chemical Society, 1972. 143]**PEER REVIEWED**

TOXICANTS CAN BE ABSORBED BY INHALATION, INGESTION, AND SKIN PENETRATION. ... ALL UNDERGO HYDROLYTIC DEGRADATION IN LIVER AND OTHER TISSUES, USUALLY WITHIN HR OF ABSORPTION. DEGRADATION PRODUCTS ARE OF LOW TOXICITY, AND ARE EXCRETED IN URINE AND FECES. /ORGANOPHOSPHATE CHOLINESTERASE-INHIBITING PESTICIDES/
[Morgan, D.P. Recognition and Management of Pesticide Poisonings. EPA 540/9-80-005. Washington, DC: U.S. Government Printing Office, Jan. 1982. 2]**PEER REVIEWED**

/THEY/ ... ARE RAPIDLY ABSORBED THROUGH MUCOUS MEMBRANE OF DIGESTIVE SYSTEM, RESPIRATORY SYSTEM & THE SKIN, & CONVEYED BY THE BLOOD TO VARIOUS BODY TISSUES. ... THE MAIN ROUTE OF ELIMINATION ... /IS/ THE KIDNEYS. /ORGANOPHOSPHORUS PESTICIDES/
[International Labour Office. Encyclopedia of Occupational Health and Safety. Vols. I&II. Geneva, Switzerland: International Labour Office, 1983. 1638]**PEER REVIEWED**

The hazard presented by application of insecticides to indoor surfaces where dermal exposure (and oral exposure in infants) may occur was investigated. Worst case assumptions for an infant playing in a room were used to calculate exposure for infant inhalation exposure, dermal exposure through contact with the floor and oral exposures due to hand/mouth contact. Surface exposure and total absorption were calculated for chlorpyrifos, dichlorvos, and propoxur. The dose calculated with each of these insecticides might reach toxic levels, particularly to an infant. Dose calculations did not consider metabolic breakdown or cumulative effects. Data necessary for determining that the levels of insecticides in the air and on treated surfaces will not be injurious to human health would include the bioavailability of surface residues, rate of transfer from surfaces and dose response data. According to the authors, risk assessments based on health protective assumptions should be used in the meantime to decide the safety of various components.
[Berteau PE et al; Biological Monitoring for Pesticide Exposure: Measurement, Estimation, & Risk Reduction, ACS Symp Series 382: 315-26 (1989)]**PEER REVIEWED**

Inhalation studies with laboratory animals have shown that it is difficult to achieve a lethal concentration in air with this compound because it is so readily absorbed on surfaces and hydrolyzed by moisture. Thus, it has been possible to kill animals (rats) by respiratory exposure only when their complete air supply was bubbled through the liquid insecticide directly into a small exposure chamber.
[American Conference of Governmental Industrial Hygienists, Inc. Documentation of the Threshold Limit Values and Biological Exposure Indices. 6th ed. Volumes I,II, III. Cincinnati, OH: ACGIH, 1991. 446]**PEER REVIEWED**

 

Mechanism of Action:

The effect of dichlorvos /in depleting glycogen stores/ seems to be due to simultaneous stimulation of glycogen phosphorylase and inhibition of glycogen synthesis.
[Hayes, Wayland J., Jr. Pesticides Studied in Man. Baltimore/London: Williams and Wilkins, 1982. 345]**PEER REVIEWED**

The main feature of the toxic mechanism of organophosphorus pesticides is inhibition of the esterase enzyme activity, in particular of cholinesterase, which plays an important physiological part. Organophosphorus pesticides can also indirectly interact with the biochemical receptors of acetylcholine. /Organophosphorus pesticides/
[International Labour Office. Encyclopedia of Occupational Health and Safety. Vols. I&II. Geneva, Switzerland: International Labour Office, 1983. 1638]**PEER REVIEWED**

The effect of dichlorvos on the contractile response of isolated rat tail arteries /revealed that at a concn of/ 1x10(-8) to 1x10(-4) M of dichlorvos had no effect on baseline tension, but relaxed 1x10(-7) M norepinephhrine, 1x10(-7) M 5-HT or 100 mM potassium chloride contractions dose dependently. Dichlorvos also inhibited calcium chloride dose response curves in potassium(+) depolarized strips, as well as depressing both phasic and tonic components of norepinephrine induced contractions. The results suggest a direct relaxant effect of dichlorvos on arterial smooth muscle by a mechanism probably related to interference with calcium(2+) supply.
[Ebeigbe AB, Campbell PI; Pharmacol Res Commun 18 (3): 283-92 (1986)]**PEER REVIEWED**

 

Interactions:

Metaproterenol (20 mg/kg), terbutaline (10 mg/kg), and salbutamol (10 mg/kg) increased the protection of atropine + trimedoxime bromide (20 mg/kg, each) against /dichlorvos/ poisoning in mice. The increased protection from the beta-2-adrenoreceptor agonists might have been due to a greater relaxation of bronchial musculature. ...
[Srivastava RK et al; 97 (3/4): 339-40 (1984)]**PEER REVIEWED**

Binding isotherms /exhibited/ a high degree (71-73 %) of reversible binding of DDVP with serum proteins. ... In a related study, prior administration of sulfadimethoxine to rats increased their sensitivity to DDVP and reduced DDVP serum binding to less than 65-66%.
[Trinus FP et al; Bull Eksp Biol Med 93 (6): 66-8 (1982)]**PEER REVIEWED**

Treatment of pregnant rabbits with phenobarbital increased the sensitivity of the progeny to the cerebrotoxic action of dichlorvos. ...
[Dambska M et al; Acta Med Pol 22 (3): 207-15 (1981)]**PEER REVIEWED**

Acetaminophen failed to potentiate the toxicity of dichlorvos on esterase /in mice/.
[Costa LG, Murphy SD; Res Commun Chem Pathol Pharmacol 44 (3): 389-400 (1984)]**PEER REVIEWED**

... Oral administration of dichlorvos 60 mg/kg (/to castrated pigs/ 3 times the anthelmintic dosage level) 1 hr before levamisole injection lowered blood cholinesterase activity to approximately 60% that of controls, but did not change the LD50 of levamisole. ... /LD50 Levamisole-hydrochloride= 39.8 mg/kg/
[Hsu WH; Am J Vet Res 42 (11): 1912-4 (1981)]**PEER REVIEWED**

In order to clarify whether or not dichlorvos (DDVP), which did not exert carcinogenic effects in mice in /previously reported studies/ is cocarcinogenic, male and female mice of the strain C57B1/6/B1n were sc injected with the carcinogen N-nitrosodiethylamine and received in addition DDVP orally. For comparison N-nitrosodiethylamine and DDVP alone was administered to other groups of mice. The combined application N-nitrosodiethylamine + DDVP did not result in increased incidences of tumors and preneoplastic lesions as compared with the N-nitrosodiethylamine treated groups of mice. The incidence of focal (transitional cell) hyperplasias of the urinary bladder epithelium was increased in the groups treated with N-nitrosodiethylamine + DDVP as compared to the groups with single compound treatment. There were no development of tumors and no differences in the latency periods of tumors which could be attributed to the combined treatment with N-nitrosodiethylamine + DDVP. Under these experimental conditions DDVP was not cocarcinogenic in mice.
[Horn KH et al; Arch Geschwulstforsch 60 (2): 1117-24 (1990)]**PEER REVIEWED**

 

Pharmacology:

 

 

Therapeutic Uses:

MEDICATION (VET): ORALLY ... ANTHELMINTIC: RECOMMENDED AGAINST HOOKWORMS, WHIPWORMS, & ROUNDWORMS IN DOGS; ADULT & 4TH STAGE WHIPWORMS, NODULAR WORMS, ... STOMACH WORMS, & ROUNDWORMS IN SWINE; BOTS, STRONGLES, & PINWORMS IN HORSES. EMBEDDED IN PLASTIC PELLETS, ITS RELEASE RATE IS GRADUAL AFTER INGESTION.
[Rossoff, I.S. Handbook of Veterinary Drugs. New York: Springer Publishing Company, 1974. 166]**PEER REVIEWED**

MEDICATION (VET): DICHLORVOS ... IS UNIQUE AMONG ORGANOPHOSPHORUS ANTHELMINTICS IN THAT IT CAN BE INCORPORATED INTO POLYVINYL CHLORIDE RESIN PELLETS. ... RELEASED SLOWLY FROM UNDIGESTIBLE PELLETS AS THEY PASS THE LENGTH OF DIGESTIVE TRACT. ... CONCN AGAINST PARASITES ALL ALONG DIGESTIVE TUBE.
[Booth, N.H., L.E. McDonald (eds.). Veterinary Pharmacology and Therapeutics. 5th ed. Ames, Iowa: Iowa State University Press, 1982. 830]**PEER REVIEWED**

MEDICATION (VET): ... INTRANASALLY AGAINST BOTS ... OF SHEEP. ... HAVE CURED SOME CASES OF DEMODECTIC MANGE IN DOGS REFRACTORY TO OTHER TREATMENTS BY HANGING ... FLY STRIPS ... IN DOG KENNELS.
[Rossoff, I.S. Handbook of Veterinary Drugs. New York: Springer Publishing Company, 1974. 166]**PEER REVIEWED**

MEDICATION (VET): TOPICALLY, FOR QUICK KNOCKDOWN OF INSECTS ON ANIMALS & PREMISES AS FOG, MIST, OR SPRAY (1%), IN SUGAR TYPE BAITS NEAR FLY BREEDING AREAS
[Rossoff, I.S. Handbook of Veterinary Drugs. New York: Springer Publishing Company, 1974. 166]**PEER REVIEWED**

 

Drug Warnings:

VET: DO NOT USE IN CONJUNCTION WITH OR WITHIN FEW DAYS OF (BEFORE &/OR AFTER) ANY OTHER CHOLINESTERASE INHIBITORS & AVOID USE WITH PHENOTHIAZINE, PHENOTHIAZONE TRANQUILIZERS, ARSENICALS, PURGATIVES, OR DRUGS PRODUCING PURGATION AS SIDE EFFECT.
[Rossoff, I.S. Handbook of Veterinary Drugs. New York: Springer Publishing Company, 1974. 166]**PEER REVIEWED**

DO NOT ADMINSTER TASK /A FORMULATION/ ... DOG ANTHELMINTIC IN CONJUNCTION WITH OTHER ANTHELMINTICS, TAENIACIDES, ANTIFILARIAL AGENTS (DIETHYLCARBAMAZINE EXCEPTED), MUSCLE RELAXANTS OR TRANQUILIZERS. /TASK/
[Aronson, C.E. (ed.). Veterinary Pharmaceuticals & Biologicals, 1980-1981. Media, Pa.: Harwal Publishing Co., 1980.,p. 19/76]**PEER REVIEWED**

DO NOT ADMIN TO DOGS SHOWING SIGNS OF SEVERE CONSTIPATION, MECHANICAL BLOCKAGE OF INTESTINAL TRACT, IMPAIRED LIVER FUNCTION, CIRCULATORY FAILURE, OR TO DOGS RECENTLY EXPOSED TO OR SHOWING SIGNS OF INFECTIOUS DISEASES.
[Aronson, C.E. (ed.). Veterinary Pharmaceuticals & Biologicals, 1980-1981. Media, Pa.: Harwal Publishing Co., 1980.,p. 19/76]**PEER REVIEWED**

 

Interactions:

Metaproterenol (20 mg/kg), terbutaline (10 mg/kg), and salbutamol (10 mg/kg) increased the protection of atropine + trimedoxime bromide (20 mg/kg, each) against /dichlorvos/ poisoning in mice. The increased protection from the beta-2-adrenoreceptor agonists might have been due to a greater relaxation of bronchial musculature. ...
[Srivastava RK et al; 97 (3/4): 339-40 (1984)]**PEER REVIEWED**

Binding isotherms /exhibited/ a high degree (71-73 %) of reversible binding of DDVP with serum proteins. ... In a related study, prior administration of sulfadimethoxine to rats increased their sensitivity to DDVP and reduced DDVP serum binding to less than 65-66%.
[Trinus FP et al; Bull Eksp Biol Med 93 (6): 66-8 (1982)]**PEER REVIEWED**

Treatment of pregnant rabbits with phenobarbital increased the sensitivity of the progeny to the cerebrotoxic action of dichlorvos. ...
[Dambska M et al; Acta Med Pol 22 (3): 207-15 (1981)]**PEER REVIEWED**

Acetaminophen failed to potentiate the toxicity of dichlorvos on esterase /in mice/.
[Costa LG, Murphy SD; Res Commun Chem Pathol Pharmacol 44 (3): 389-400 (1984)]**PEER REVIEWED**

... Oral administration of dichlorvos 60 mg/kg (/to castrated pigs/ 3 times the anthelmintic dosage level) 1 hr before levamisole injection lowered blood cholinesterase activity to approximately 60% that of controls, but did not change the LD50 of levamisole. ... /LD50 Levamisole-hydrochloride= 39.8 mg/kg/
[Hsu WH; Am J Vet Res 42 (11): 1912-4 (1981)]**PEER REVIEWED**

In order to clarify whether or not dichlorvos (DDVP), which did not exert carcinogenic effects in mice in /previously reported studies/ is cocarcinogenic, male and female mice of the strain C57B1/6/B1n were sc injected with the carcinogen N-nitrosodiethylamine and received in addition DDVP orally. For comparison N-nitrosodiethylamine and DDVP alone was administered to other groups of mice. The combined application N-nitrosodiethylamine + DDVP did not result in increased incidences of tumors and preneoplastic lesions as compared with the N-nitrosodiethylamine treated groups of mice. The incidence of focal (transitional cell) hyperplasias of the urinary bladder epithelium was increased in the groups treated with N-nitrosodiethylamine + DDVP as compared to the groups with single compound treatment. There were no development of tumors and no differences in the latency periods of tumors which could be attributed to the combined treatment with N-nitrosodiethylamine + DDVP. Under these experimental conditions DDVP was not cocarcinogenic in mice.
[Horn KH et al; Arch Geschwulstforsch 60 (2): 1117-24 (1990)]**PEER REVIEWED**

 

Environmental Fate & Exposure:

 

 

Environmental Fate/Exposure Summary:

Dichlorvos' production and use as an insecticide in sprays, household and commercial resin strips, and flea collars that are applied to animals, including livestock and pets, and crops will result in its direct release to the environment. If released to air, a vapor pressure of 0.0158 mm Hg at 25 deg C indicates dichlorvos will exist solely as a vapor in the ambient atmosphere. Vapor-phase dichlorvos will be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals; the half-life for this reaction in air is estimated to be 13.6 hours. Dichlorvos hydrolyzes in water by a base-catalyzed process. After 24 hr, 8% and 90% degradation occurred at pH 6.2 and pH 9.3, respectively. Biodegradation may also be a factor in situations where acclimated colonies of microorganisms exist or under acidic conditions when hydrolysis is slower. The estimated volatilization half-life of dichlorvos in a model river is 119 days. Experimental studies indicate that dichlorvos does not bioconcentrate in fish. The whole and body BCF in carp is <0.5 and the insecticide's excretion half-life is 0.6 hr. Based upon a Koc of 47, dichlorvos would be expected to exhibit high mobility in soil and not adsorb to suspended solids and sediment in water. Volatilization from water surfaces and moist soil surfaces is not expected to be an important fate process based upon an estimated Henry's Law constant of 4.6X10-7 atm-cu m/mole. When applied to soil, dislodgeable residue levels on foliage and turf rapidly decline to safe reentry levels in several hours. Dichlorvos degrades in soil by hydrolysis and biodegradation. Half-lives determined in a variety of soils range from 1.5 to 17 days. The general population will be primarily exposed to dichlorvos by inhalation of indoor air where dichlorvos is used as an insecticide. Occupational exposure will primarily be by inhalation and dermal contact in situations where the insecticide is used or stored. (SRC)
**PEER REVIEWED**

 

Probable Routes of Human Exposure:

Dichlorvos can affect the body if it is inhaled, if it comes in contact with the eyes or skin, or is swallowed. ...
[Mackison, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (eds.). NIOSH/OSHA - Occupational Health Guidelines for Chemical Hazards. DHHS(NIOSH) PublicationNo. 81-123 (3 VOLS). Washington, DC: U.S. Government Printing Office, Jan. 1981. 1]**PEER REVIEWED**

NIOSH (NOES Survey 1981-1983) has statistically estimated that 11,182 workers (2,182 of these are female) are potentially exposed to dichlorvos in the US(1). The NOES Survey does not include agricultural workers. Occupational exposure to dichlorvos may occur through inhalation of ambient air and dermal contact with this compound at workplaces where dichlorvos is produced or used for household and public health insect control, flea collars and no-pest strips(2,SRC). Similarly, the general population may be exposed to dichlorvos via inhalation of air and dermal contact when no-pest strips, sprays or flea collars containing this insecticide are used. Exposure could also result from ingestion of food which has been prepared in rooms where dichlorvos is used for insect control(SRC). As part of EPA's Non-Occupational Pesticide Exposure Study (NOPES) conducted in the Summer 1986, Spring 1987 and Winter 1988 in Jacksonville, FL and Springfield/Chicopee, MA the estimated mean personal air concn of dichlorvos for Jacksonville residents was 147.6, 40.2, and 21.4 ng/cu m in summer, spring and winter, respectively(3). The estimated spring and winter concns for Springfield/Chicopee residents were 3.7 and 2.1 ng/cu m in spring and winter. In Jacksonville, it was estimated that the percentage of residents with detectable levels of dichlorvos in personal air was 35%, 11%, and 16% in summer, spring and winter, respectively. In Springfield/Chicopee only 2% and 1% of residents were exposed in spring and winter. Exposure from air inhalation was the primary route of exposure to dichlorvos(3).
[(1) NIOSH; National Occupational Exposure Survey (NOES) (1983) (2) Lewis RG et al; APCA Annual Meeting #79 Research Triangle Park,NC: USEPA 2: 15 (1986) (3) Whitmore RW et al; Arch Environ Contam Toxicl 26: 47-59 (1994)]**PEER REVIEWED**

Dichlorvos was detected in the workplace environment in concns of 77 ppb in air during production and processing of a dichlorvos-releasing vaporizer(1). During spraying of an orchard 130 ppb was detected in air and a rate of skin contamination of 72 ug/100 sq cm/hr was reported(1). After spraying, 114-765 ug/sq m of dichlorvos was deposited on worker's clothing(3). A study was performed to determine the level of exposure to 5 workers after 1.85 kg of dichlorvos was sprayed on an apple orchard for 5.5 hr with an airblast sprayer(4). The air and breathing zone dichlorvos concns were 1.0-15.4 ug/cu m, and 113.6-765.3 ug/cu m, respectively. Ambient air in storage rooms of four North Carolina commercial pest control firms (4 hr period) contained 147-1501 ng/cu m, (617 ng/cu m avg)(2). Ambient air in offices of four North Carolina commercial pest control firms (4 hr period) contained 19-66 ng/cu m, (41 ng/cu m avg)(2). A 1993 study of insecticide concns in the air of 10 North Carolina pest control firms (19 samples) resulted in mean dichlorvos air levels of 1.48 ug/cu m(5). Levels were higher in summer than in winter. In a study to determine the dissipation of dislodgeable residues of dichlorvos on turf, the residue level was 0.10 ug/sq cm immediately post application (<2 hr) and rapidly declined to below the safe level for reentry, 0.06 mg/sq cm after two hours and was undetectable (<1 ug/sample) after 23 hr(5). There was no significant difference in post application dissipation of dislodgeable residues between irrigated and non-irrigated plots. Dichlorvos was detected in air samples immediately post-spray at 1.9 ppb(5). Three hours after application of dichlorvos to greenhouse crops using low-volume (<50 l/ha) techniques, the atmospheric concn of dichlorvos had declined to 12% of the initial concn but was still exceeding the 1000 ug/cu m threshold limit value (TLV)(6).
[(1) IARC; Some Halogenated Hydrocarbons 20 (1979) (2) Wright CG, Leidy RB; Bull Environ Contam Toxicol 24: 582-9 (1980) (3) Okuno T et al; Kankyo Kagaku 4: 470-1 (1994) (4) Okuno T et al; Hyogo-kenritsu Eisei Kenkyusho Nenpo 31: 73-80 (1996) (5) Wright CG et al; Bull Environ Contam Toxicol 56: 21-8 (1996) (6) Brouwer DH et al; Chemosphere 24: 1157-69 (1992)]**PEER REVIEWED**

 

Body Burden:

Two pest control operators in Japan involved in spraying and mixing a combined emulsifiable concentrate of fenithrothion and dichlorvos to exterminated cockroaches in household construction contained mean and maximum alkyl phosphate levels in urine of 0.099 and 0.22 ug/mg creatinine(1).
[(1) Takamiya K; Bull Environ Contam Toxicol 52:190-5 (1994)]**PEER REVIEWED**

 

Average Daily Intake:

AIR INTAKE: 1.25 ug (Jacksonville, FL; assuming a weighted estimate of average daily air concns of 62.4 ng/cu m(1)); 0.066 ug (Springfield/Chicopee, MA; assuming a weighted estimate of average daily air concns of 3.3 ng/cu m(1)).
[(1) Whitmore RW et al; Arch Environ Contam Toxicl 26: 47-59 (1994)]**PEER REVIEWED**

 

Natural Pollution Sources:

Dichlorvos is not known to occur as a natural product(1).
[(1) IARC; Some Halogenated Hydrocarbons 20 (1979)]**PEER REVIEWED**

 

Artificial Pollution Sources:

Dichlorvos' production and use as an insecticide used in sprays, resin strips, and flea collars that are applied to animals, including livestock and pets, and crops(1) will result in its direct release to the environment (SRC). Its extensive use against sea-lice parasites in cage-cultures of salmon farming in Ireland(2) indicates that it is released into seawater. Dichlorvos is also a breakdown product of the insecticide trichlorphon(1) and may be released to the environment when trichlorphon is used.
[(1) IARC; Some Halogenated Hydrocarbons 20 (1979) (2) Eades JF; Aquat. Environ., Proc Eur Symp, 6th, pp. 497-501 (1991)]**PEER REVIEWED**

 

Environmental Fate:

Octanol water partition coefficients and air water partition coefficients were obtained for 10 organochlorine pesticides (including dichlorvos) as basic data for predicting their fate in the environment. The octanol water partition coefficient is ... 1.45X10+1 for dichlorvos. These values approximately correlated with the solubilities of these pesticides in water. The air water partition coefficient is ... 5.0X10-3 for dichlorvos.
[Kawamoto K, Urano K; Chemosphere 18 (9-10): 1987-96 (1989)]**PEER REVIEWED**

TERRESTRIAL FATE: When spilled on soil, dichlorvos leached into the ground with 18-20% penetrating to 30 cm within 5 days. Dichlorvos degrades in soil by both hydrolysis and biodegradation(7). In a soil perfusion experiment using Houston Black Clay (pH 7.7), 71% degradation occurred after 10 days in a non-sterile system while 50% occurred in a sterile system(1). Half-lives of 7 days were obtained in clay, sandy-clay, and loose sandy soil(1). A half-life of 1.5 days was obtained in field plots with chestnut soil(2) and 17 days in an unidentified soil(3). It disappeared from soil as well as foliage when sprayed on a vineyard in the USSR(4). Dissipation rates of dislodgeable dichlorvos residues were measured on lawns with and without postspray irrigation(5). Residue levels for all application scenarios rapidly declined to below 0.06 ug/sq cm, the safe reentry level, within six hours post spray(5). The half-life of dichlorvos was determined in 16 sediment samples (pH ranging from 8.2 to 9.2) from the Bay of Bengal(6). The half-lives were determined with all exchangeable ions present as well with the exchangeable ions removed. The half-lives ranged from 36 days (lower pH) to 12 days (higher pH). With the exchangeable ions removed, the respective half-lives ranged from 40 days to 25 days. The shorter half-lives in the presence of exchangeable ions are believed to reflect a catalytic effect exerted on the exchangeable ions(6). Half-lives in sediment were shorter. Based on a classification scheme(11), the experimental Koc value of 47(9), indicates that dichlorvos will have high mobility in soil(SRC). Volatilization of dichlorvos from moist soil surfaces is not expected to be an important fate process (10,SRC) based upon an estimated Henry's Law constant of 4.6X10-7 atm-cu m/mole(SRC), derived from its vapor pressure and water solubility and its low adsorption to soil(8).
[(1) Nowinska J, Wybieralski J; Zesz Nauk Akad Roln Szczecinie 38: 299-303 (1979) (2) Korotova LG, Denchenko AS; Giokim Mater 74: 99-103 (1978) (3) Menzie CM; Annual Rev Ent 17: 199-222 (1972) (4) Bolotnyi AV et al; Gig Sanit 5: 28-31 (1978) (5) Goh KS et al; Bull Environ Contam Toxicol 37: 33-40 (1986) (6) Sarkar A, Gupta RS; Indian J Marine Sci 15: 72-4 (1986) (7) Lamoreaux RJ, Newland LW; Chemosphere 10: 807-14 (1978) (8) Meylan WM, Howard PH; Environ Toxicol Chem 10: 1283-93 (1991) (9) Kawamoto K, Urano K; Chemosphere 19: 1223-31 (1989) (10) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington,DC: Amer Chem Soc Chapt 16 (1990) (11) Swann RL et al; Res Rev 85: 23 (1983)]**PEER REVIEWED**

AQUATIC FATE: When released into the environment, dichlorvos will partition predominantly to water, reflecting its high water solubility(7). It will degrade primarily by hydrolysis although biodegradation may be important where acclimated microorganisms may exist such as some polluted waters or where the water is more acidic and hydrolysis slower(SRC). Hydrolysis is base catalyzed. In one experiment, a 64% disappearance was observed in 24 hr at pH 8.7 and only 8% at pH 6.2(1). Below pH 3.3, no degradation occurred after 96 hr(1). After its addition to seawater at concn of 0.419 mg/l, the concn decreased only slightly to 0.359 mg/l in 9 days(4). Conflicting hydrolysis data were obtained in water samples prepared with phosphate buffers and NaCl to be the aqueous counterpart of sediment samples obtained from the Bay of Bengal(5). The half-life of dichlorvos in fresh water ranged from 40 to 60 days in samples where the pH ranged from 9.2 to 8.2(5). In brackish water of similar pH values, the half-life ranged from 50 to 70 days(5). The decreasing rate of hydrolysis with increasing salinity is thought to be due to decreased mobility of the hydroxyl ions(5). In studies performed on a mixture of pesticides studied over a 6-month period in different water types at 22 deg C, dichlorvos disappeared after 81 days, 55 days and 34 days in ultrapure water (pH 6.1), river water (pH 7.3), and filtered river water (pH 7.3), respectively; it was present after 6 months in seawater (pH 8.1)(6). Based on a classification scheme(8), the experimental Koc value of 47(2), indicates that dichlorvos will not adsorb to suspended solids and sediment in water(SRC). Dichlorvos is not expected to volatilize from water surfaces(3,SRC) based upon an estimated Henry's Law constant of 4.6X10-7 atm-cu m/mole(SRC), derived from its vapor pressure and water solubility(9). Its estimated volatilization half-life for a model river is 119 days(3,SRC). Experimental BCF values of <0.5 and 0.8 in carp(10) and willow shiner(11), respectively and a excretion half-life of 0.6 hr in carp(10) indicate that dichlorvos will not bioconcentrate in fish(SRC).
[(1) Lamoreaux RJ, Newland LW; Chemosphere 10: 807-14 (1978) (2) Kawamoto K, Urano K; Chemosphere 19: 1223-31 (1989) (3) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington,DC: Amer Chem Soc pp. 15-1 to 15-29 (1990) (4) Eades JF; Aquat. Environ., Proc Eur Symp, 6th, pp. 497-501 (1991) (5) Sarkar A, Gupta RS; Indian J Marine Sci 15: 72-4 (1986) (6) Lartiges SB, Garrigues PP; Environ Sci Technol 29: 1246-54 (1995) (7) Yenigun O, Sohtorik D; Water, Air, Soil Pollution 84: 175-85 (1995) (8) Swann RL et al; Res Rev 85: 23 (1983) (9) Meylan WM, Howard PH; Environ Toxicol Chem 10: 1283-93 (1991) (10) Abd-Allah AMA; Alex. Sci. Exch 16: 61-9 (1995) (11) Tsuda T et al; Chemosphere 25: 1945-51 (1992)]**PEER REVIEWED**

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), dichlorvos, which has a vapor pressure of 0.0158 mm Hg at 25 deg C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase dichlorvos is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals(SRC); the half-life for this reaction in air is estimated to be 13.6 hr(SRC) from its estimated rate constant of 9.4E-12 cu cm/molecule-sec(3). Droplets containing dichlorvos as a result of spraying will be removed from the air by gravitational settling(SRC). The fact that dichlorvos has been detected in air a week after spraying has been ascribed to its volatility after being adsorbed on plants and soil(4).
[(1) Bidleman TF; Environ Sci Technol 22: 361-367 (1988) (2) Tomlin C; The Pesticide Manual, 10th ed, Crop Protection Publications (1994) (3) Meylan WM, Howard PH; Chemosphere 26: 2293-99 (1993) (4) Hanai Y et al; Yokahama Kokuritsu Daigaku Kankyo Kagaku Kenkyyu Senta Kiyo 12: 47-59 (1985)]**PEER REVIEWED**

 

Environmental Biodegradation:

AEROBIC: Dichlorvos is listed as being amenable to biological treatment after acclimation(1). It was resistant to degradation (8-14% of theoretical BOD) in an 8 day laboratory test using a sewage inoculum(2). The biodegradation rate constant and half-life for dichlorvos was determined to be 0.20 1/d and 3.5 days, respectively in an aerobic biodegradability test using an activated sludge inoculum at 20 deg C and GC analysis(8). Dichlorvos was not completely removed when incubated with sewage for 7 days at 29 deg C; biodegradation products are dichloroethanol, dichloroacetic acid and ethyl dichloroacetate(5). There is some evidence that it degrades somewhat faster in polluted than unpolluted waters(3,4). Dichlorvos is degraded by soil microorganisms although much of the degradation in soil is chemical in nature. In a soil perfusion experiment, 71% degradation occurred in 10 days but only 30% was due to biodegradation(6). The presence of active microorganisms reduced the half-life of dichlorvos in clay and calcareous soil from 0.9 to 0.75 days and 0.85 to 0.70 days, respectively(7). The average first-order rate constant and half-life of dichlorvos in an acidic silty clay soil and a neutral sandy clay soil was 0.0423 and 0.04443, respectively(8). The half-life in both cases was 16 days. The rate was about 1.4 times faster with a 10 ppm loading than a 100 ppm loading. Dichlorvos was completely degraded on passage through a sand column, whereas no degradation occurred when the sand was sterilized(10).
[(1) Thom NS, Agg AR; Proc Roy Soc Lond B 189: 347-57 (1975) (2) Rosenberg A et al; Microbial degradation of pesticides. Cornell Univ, Ithaca, NY. N00014-78-C-0044 (1979) (3) Drevenkar V et al; Archiv Za Higyino Roda I Toksikologiju 26: 257-66 (1975) (4) Yasuno M et al; Japan J Exp Med 35: 545-63 (1966) (5) Lieberman MT, Alexander M; J Agric Food Chem 31: 265-7 (1983) (6) Lamoreaux RJ, Newland LW; Chemosphere 10: 807-14 (1978) (7) Guerguis MW, Shafik MT; Bull Entomol Soc Egypt Econ Ser 8: 29-32 (1975) (8) Kawamoto K, Urano K; Chemosphere 21: 1141-52 (1990) (9) Sattar MA; Chemosphere 20: 387-96 (1990) (10) Oshida H et al; pp. 29-1, 362-6 in Tokyo-toritsu Eisei Kenkyusho Kenkyu Nemso (1978)]**PEER REVIEWED**

ANAEROBIC: Low concn of dichlorvos (3 mg-C/l) degraded within 7 days in an anaerobic biodegradability test at 37 deg C(1). The biodegradation rate constant and half-life for dichlorvos was determined to be 0.20 1/d and 3.5 days, respectively in an anaerobic biodegradability test using 30 mg/l anaerobic microorganisms cultured by an artificial sewage at 20 deg C under nitrogen and GC analysis(8). The investigators obtained the same rate for aerobic biodegradation.
[(1) Kameya T et al; Sci Total Environ 170: 43-50 (1995)]**PEER REVIEWED**

 

Environmental Abiotic Degradation:

Dichlorvos absorbs light in the UV with a maximum absorbance and extinction coefficient between 295 and 305 nm of 0.0246 and 54 l/mol-cm, respectively(1). Despite this relatively low extinction coefficient, the degradation of dichlorvos in a thin film (0.67 ug/sq cm) was rapid; the photodegradation rate constant and half-life are 265.2X10-7 1/sec and 7.25 hr, respectively(1). Dichlorvos hydrolyzes in water; the rate of hydrolysis increases with pH(2-4), temperature(2,3), and concentration(2). Dichlorvos is stable at pH <3.3(4). The neutral and basic hydrolysis rate constants at 20 deg C are reported as 36.7X10-4 1/hr and 20790 1/M-hr, respectively(9). Eight, 18, 64, and 90% degradation was observed in 24 hr at pH 6.2, 8.2, 8.7 and 9.3, respectively(4). Another study found that the hydrolysis half-life decreased from 77 hr to 5 hr when the pH increased from 5.4 to 8 at 37.5 deg C(3). At pH 5, the half-life was 10.0, 2.6, and 0.7 days at 10, 20, and 30 deg C, respectively(3). The half-life was >72 hr in water from 3 Yugoslav rivers(5) and approximately 100 hr in a German lake whose pH was <6 and temperature below 5 deg C(6). Hydrolysis is an important degradation mechanism in soils(7). While 71% of dichlorvos added to Houston black clay degraded in 10 days, 70% of the degradation was attributed to hydrolysis(4). The half-lives of dichlorvos in autoclaved clay soil and calcareous soil were 0.9 and 0.85 days, respectively(8,SRC).
[(1) Chen ZM et al; Ind Eng Chem Prod Res Dev 23: 5-11 (1984) (2) Drevenkar V et al; Archiv Za Higyino Roda I Toksikologiju 26: 257-66 (1975) (3) Faust SD, Suffet IH; Res Rev 15: 44 (1966) (4) Lamoreaux RJ, Newland LW; Chemosphere 10: 807-14 (1978) (5) Drevenkar V et al; Archiv Za Higyuno Roda I Toksikologiju 26: 257-66 (1975) (6) Grahl K; Z Binnenfisch DDR 26: 312-6 (1979) (7) Luberman MT, Alexander M; J Agric Food Chem 31: 265-7 (1983) (8) Guerguis MW, Shafik MT; Bull Entomal Soc Egypt Econ Ser 8: 29-32 (1975) (9) Falah IZ, Hammers WE; Toxicol Environ Chem 42: 9-18 (1994)]**PEER REVIEWED**

The rate constant for the vapor-phase reaction of dichlorvos with photochemically-produced hydroxyl radicals has been estimated as 9.41 cu cm/molecule-sec at 25 deg C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of 13.6 hours at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). The rate constant for the vapor-phase reaction of dichlorvos with ozone has been estimated to be 3.58X10-11 cu cm/molecule-sec at 25 deg C(1) which corresponds to an atmospheric half-life of about 320 days at an atmospheric concentration of 7X10+11 molecules per cu cm(1). The concentrations of hydroxyl radicals and ozone used to estimate the half-lives are representative of outdoor air and may not be appropriate for indoor air where dichlorvos is mostly used(SRC).
[(1) Meylan WM, Howard PH; Chemosphere 26: 2293-99 (1993)]**PEER REVIEWED**

 

Environmental Bioconcentration:

The log BCF for dichlorvos estimated from its log octanol/water partition coefficient, 1.47, is 1.26(1). This value was selected from results predicted using seven different equations and indicates that dichlorvos will not bioconcentrate in fish. The whole-body bioconcentration factor measured in carp was <0.5 after 168 hr(2). The excretion rate and half-life were 0.56 1/hr and 0.6 hr, respectively indicating that dichlorvos is readily eliminated from carp(2). The average whole-body BCF of dichlorvos in willow shiner after 24 and 168 hr was 0.8(3). The concentration of dichlorvos in the fish was low and rapidly decreased; the excretion rate constant could not be determined.
[(1) Devillers J et al; Chemosphere 33: 1047-65 (1996) (2) Abd-Allah AMA; Alex Sci Exch 16: 61-9 (1995) (3) Tsuda T et al; Chemosphere 25: 1945-51 (1992)]**PEER REVIEWED**

 

Soil Adsorption/Mobility:

The Koc for dichlorvos calculated from its water solubility and octanol/water partition coefficient are 28(1) and 47(5), respectively. The Freundlich adsorption constants were determined in 3 Japanese black soils with organic carbon contents ranging from 2.3% to 6.8% and a sodium-bentonite clay by shaking in serum bottles for 24 hr at 25 deg C until the system was equilibrated(4). The Freundlich adsorption constant Kf was 3.6, 2.4 and 1.0 for the 3 black soils and the Freundlich exponent, 1/n, was 1/0.78; Kf for the clay mineral was <0.2. The Koc derived from Kf was 47. According to a classification scheme(6), these estimated and measured Koc values suggest that dichlorvos will have high mobility in soil(SRC). In a field experiment, 18-20% of the dichlorvos which was sprayed on the ground had penetrated the soil to a depth of 30 cm within 5 days(2). In a soil TLC study, mobility was measured and the effects of various soil properties were determined; Rf values ranged from 0.36 to 0.74(3). The mobility of dichlorvos in soil is decreased by the addition of soil amendments such as calcium carbonate(7). Mobility in soil decreases with increasing soil pH(8).
[(1) Kenaga EE; Ecotox Environ Safety 4: 26-38 (1980) (2) Petrova TM, Novozhilov KV; Migr Zagryaz Vishchestv Pochvakh Sopredil'nykh Sridakh Tr Vses Soveshch 2: 136-43 (1980) (3) Khan S, Khan NN; Soil Sci 142: 214-22 (1986) (4) Kawamoto K, Urano K; Chemosphere 19: 1223-31 (1989) (5) Sablijic A et al; Chemosphere 31: 4489-514 (1995) (6) Swann RL et al; Res Rev 85: 23 (1983) (7) Sharma SR et al; Ecotox Environ Safety 10: 339-50 (1985) (8) Sharma SR et al; Ecotox Environ Safety 11: 229-40 (1986)]**PEER REVIEWED**

 

Volatilization from Water/Soil:

The Henry's Law constant for dichlorvos is estimated as 4.6X10-7 atm-cu m/mole(SRC) from its vapor pressure, 0.0158 mm Hg(1), and water solubility, 10,000 mg/l(2). This Henry's Law constant indicates that dichlorvos should slowly volatilize from water surfaces(3). Based on this Henry's Law constant, the volatilization half-life from a model river (1 m deep, flowing 1 m/sec, wind velocity of 3 m/sec)(3) is estimated as 119 days(SRC). The volatilization half-life from a model pond, which considers the effect of adsorption(5), has been estimated to be over 400 days(SRC). The average decrease of dichlorvos after seven days of aeration in water was 16%/day(4). Without aeration, the average decrease was 6%/day(4). Dichlorvos' estimated Henry's Law constant(1,2) indicates that slow volatilization from moist soil surfaces may also occur(SRC). Based upon its vapor pressure, dichlorvos is not expected to volatilize from dry soil surfaces(SRC).
[(1) Tomlin C; The Pesticide Manual, 10th ed, Crop Protection Publications (1994) (2) Worthing CR, Walker SB, eds; The Pesticide Manual 7th ed Croydon, England: The British Crop Protection Council (1983) (3) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington,DC: Amer Chem Soc pp. 15-1 to 15-29 (1990) (4) Oshida H et al; pp. 29-1, 362-6 in Tokyo-toritsu Eisei Kenkyusho Kenkyu Nemso (1978) (5) USEPA; EXAMS II Computer Simulation (1987)]**PEER REVIEWED**

 

Environmental Water Concentrations:

SURFACE WATER: Dichlorvos has been detected in a water reservoir and water supply-irrigation system in the USSR and in 4 polluted rivers(1). On September 9 to 11, 1988, dichlorvos was detected in marine waters of Beirtreach Bay, Ireland at concentrations up to 0.13 ug/l(2). Dichlorvos was found in the Yamaska River and its tributaries in Quebec, Canada in 1986-7(3). Its concn at a site near the mouth of the river was 8.2 and 1.7 ng/l on two occasions; it was not detected on two other occasions. Dichlorvos was detected in the Neya-gawa River in Osaka City and Osaka Bay, Japan during monitoring studies conducted in 1989-1990; concn levels were not reported(4). Dichlorvos was not found in monthly samples of surface water taken at six sites between August 1989 and January 1990 in an area of the Netherlands used for bulb culture(5).
[(1) IARC; Some Halogenated Hydrocarbons 20: 97-127 (1979) (2) Tully O, Morrissey D; Marine Pollut Bull 20: 190-1 (1989) (3) Maquire RJ, Tkacz; Arch Environ Contam Toxicol 25: 220-6 (1993) (4) Fukushima M et al; Water Sci Technol 25: 271-8 (1992) (5) Baumann RA et al; Pesticides in surface water of the Hogeveene Polder (1989/90). NTIS PB93-102 390. Rijksinstitut voor de Volksgezondheid en Milieuhygiene Bilthoven (Netherlands) (1991)]**PEER REVIEWED**

DRINKING WATER: No dichlorvos was detected in California well water performed between 7/1/94 and 6/30/95 as part of the state's well water inventory in which 46 wells in 7 counties were sampled(1).
[(1) Maquire RJ, Tkacz; Arch Environ Contam Toxicol 25: 220-6 (1993)]**PEER REVIEWED**

 

Effluent Concentrations:

Dichlorvos was detected in wastewater from a dichlorvos production plant in Bulgaria 16 g/l(1). As a result of a fire at Sandoz Ltd near Basel, Switzerland in November 1986, it was estimated that 1-3 kg was discharged into the Rhine River; the estimated water concn at Village-Neuf was 0.15-0.65 ug/l(2).
[(1) IARC; Some Halogenated Hydrocarbons 20: 97-127 (1979) (2) Capel PD et al; Environ Sci Technol 22: 992-7 (1988)]**PEER REVIEWED**

 

Atmospheric Concentrations:

URBAN/SUBURBAN: As part of EPA's Non-Occupational Pesticide Exposure Study (NOPES) conducted in the Summer 1986, Spring 1987 and Winter 1988 in Jacksonville, FL and Springfield/Chicopee, MA the estimated mean outdoor air concn of dichlorvos in Jacksonville was 0, 0, and 3.2 ng/cu m in summer, spring and winter, respectively(2). Dichlorvos was not detected in outdoor air in Springfield/Chicopee in spring and winter. It was not detected in the air of Kitakyushu City, Japan(1).
[(1) Haraguchi K et al; Atmos Environ 28: 1319-25 (1994) (2) Whitmore RW et al; Arch Environ Contam Toxicol 26: 47-59 (1994)]**PEER REVIEWED**

INDOOR AIR: As part of EPA's Non-Occupational Pesticide Exposure Study (NOPES) conducted in the Summer 1986, Spring 1987 and Winter 1988 in Jacksonville, FL and Springfield/Chicopee, MA the estimated mean indoor air concn of dichlorvos for Jacksonville residents was 134.5, 86.2, and 24.5 ng/cu m in summer, spring and winter, respectively(3). The estimated spring and winter concns for Springfield/Chicopee residents were 4.3 and 1.5 ng/cu m in spring and winter. In Jacksonville, it was estimated that the percentage of residents with detectable levels of dichlorvos in indoor air was 33%, 14%, and 10% in summer, spring and winter, respectively. In Springfield/Chicopee only 2% and 1% of residents were exposed in spring and winter. A study comparing the concn of indoor pesticides in air and household dust that determined dichlorvos levels in 7 representative New Jersey homes, found only one house with detectable air concn of dichlorvos; the average level in this house was 254.7 ng/cu m(4). No dichlorvos was found in household dust in this house. Concn levels in households and food shops in which commercial pesticide strips were used were 0-26 ppb and <1-3 ppb, respectively(1). Trials were conducted in the U.K., Australia and France between 1967 and 1970 to determine the concn of dichlorvos in the air of homes using "Vapona" strips(2). Results from more than 3000 samples of air indicated that the great majority of values were 0.1 ug dichlorvos/liter of air or less; values ranged from <0.01 to 0.24 ug/l with the higher values being associated with closed up homes or the use of multiple strips. In each trial the concn of dichlorvos rose rapidly and then fell exponentially. In temperate area trials, the concn was highest 1-2 weeks after placing the strips; the geometric mean of all values at this time was 0.04 ug/l and 3 months after placement the mean concn was 0.01 ug/l(2).
[(1) IARC; Some halogenated hydrocarbons 20: 97-127 (1979) (2) Elgar KE, Steer BD; Pestic Sci 3: 591-600 (1972) (3) Whitmore RW et al; Arch Environ Contam Toxicol 26: 47-59 (1994) (4) Roinestad KS et al; J AOAC International 76: 1121-6 (1993)]**PEER REVIEWED**

 

Food Survey Values:

In FDA's Total Diet Study (1986-1991) in which foods prepared for consumption from different regions of the country are analyzed and mean daily intakes for diet for a variety of age-sex groups determined, the mean daily intake per unit body weight of dichlorvos was <0.0001 ug/kg body weight-day(1). Less than 2% of the 4914 items of food analyzed contained dichlorvos. A further FDA study in which 234 ready-to-eat foods were tested 37 times each over a 10 year period found only one item containing dichlorvos at 0.0100 ug/g(2). The FDA found no dichlorvos residues in a targeted 1992-1993 study of 1219 domestic and 144 imported samples of tomatoes(3). In a 1993-1994 FDA study of domestic and imported apples (1831 samples) and rice (1210 samples), dichlorvos was only found on 1 sample of domestic rice at 0.08 ppm(4). A pesticide residue screen program (1989-1991) involving 6970 produce samples found only 1 sample of radishes containing dichlorvos above the detection limit of 0.25 ppm(5). The percent occurrence of dichlorvos in FDA's Residue Monitoring studies in 1978-1982 and 1982-1986 was <1% and <2%, respectively(6,7). The concn of dichlorvos on postharvest-treated potatoes declined with half-lives of 45 days at a storage temperature of -5 deg C (single phase) and 1.6 days, 11 days (two-phase) at a storage temperature of 19.7 deg C(12). After the sixth week when some potatoes were processed into starch, 3% of the residue remained on the potatoes after washing and no residue was found in the starch(12). Detected in 5.3% of fruits and vegetables produced in Gifu Prefecture, Japan(8). Dichlorvos was detected in 1 of 47 samples from France at a concn of 0.2 mg/kg(10). A 1964 to 1968 survey of Swedish fruits and vegetables showed apples, lettuce and potatoes contained dichlorvos(11). Dichlorvos concns reported in various food items (item, concn): Stored wheat, 2.4-6.0 ppm decreasing to 0.5 ppm or less over 6 weeks; Cereal products, 0 ppm; flour, 0-5.8 ppm; Crude soy bean oil and meal, <1 ppm; Malt and worts, 0-2 ppm; Raspberries, 0.2-7.0 ppm; Vegetable food products, 0.24 ppm(9). Dichlorvos was also detected in mushrooms(9). Prepared food which was experimentally exposed to air containing 3 to 60 ppb dichlorvos contained concns of 5 to 1653 ppm(9). Foods prepared in households and food shops in which commercial pest strip were used contained dichlorvos at concns ranging from <10 to 120 ppb and <50 ppb, respectively, when the dichlorvos in the ambient air ranged from 0 to 26 ppb and <1-3 ppb, respectively(9).
[(1) Gunderson EL; J Assoc Off Anal Chem 78: 1353-63 (1995) (2) Rogers WM et al; J Assoc Off Anal Chem 78: 614-31 (1995) (3) Roy RR et al; J Assoc Off Anal Chem 78: 930-40 (1995) (4) Roy RR et al; J AOAC Internat 80: 883-94 (1997) (5) Schattenberg HJ III, Hsu JP; AOAC Internat 75: 925-33 (1992) (6) Yess NJ et al; Assoc Off Anal Chem 74: 265-72 (1991) (7) Yess NJ et al; Assoc Off Anal Chem 74: 273-80 (1991) (8) Kasugo Y, Nakaya K; Gifu-Ken Eisei Kenhyusho Ho 21: 44-6 (1976) (9) IARC; Some halogenated hydrocarbons 20: 97-127 (1979) (10) Osborne BG et al; Pestic Sci 27: 103-9 (1989) (11) Renvall S, Akerblom M; Res Rev 34: 1-26 (1971) (12) Tsumura-Hagegawa Y et al; J Agric Food Chem 40: 1240-4 (1992)]**PEER REVIEWED**

 

Plant Concentrations:

Dichlorvos was detected in the leaves of cabbage and onion plants during the first 7 days after spraying(1). The half-life of dislodgeable foliar residues of dichlorvos applied by low-volume spraying of and emulsifiable concentrate (550 g/l) at 50 g ai/1000 sq m on chrysanthemum seedlings was estimated as 0.2 days in each of two experiments(2). This indicates that dichlorvos residues on plants would rapidly decline(SRC).
[(1) IARC; Some halogenated hydrocarbons 20: 97-127 (1979) (2) Brouwer DH et al; Bull Environ Contam Toxicol 58: 976-984 (1997)]**PEER REVIEWED**

 

Fish/Seafood Concentrations:

None of the 92 samples of farmed salmon analyzed as part of a farmed fish surveillance in the U.K. between 10/87 and 2/89 contained residues of dichlorvos(1).
[(1) Kay JF; Residues of Veterinary Drugs in Food, Vol 2, Haagsmam Netal Eds, (Proc Euro Residue II), May 3-15, 1993. pp. 404-9 (1993)]**PEER REVIEWED**

 

Animal Concentrations:

Dichlorvos was found in sheep organs and in the tissue of cattle, 7 days and 15-22 days after application of trichlorphon, respectively.
[IARC. Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Man. Geneva: World Health Organization, International Agency for Research on Cancer,1972-PRESENT. (Multivolume work).,p. V20 101 (1979)]**PEER REVIEWED**

 

Milk Concentrations:

Dichlorvos was detected in milk and dairy products(1,2).
[(1) Cerutti G et al; Latte 3: 161-5, 170-5 (1975) (2) IARC; Some Halogenated Hydrocarbons 20 (1979)]**PEER REVIEWED**

 

Environmental Standards & Regulations:

 

 

FIFRA Requirements:

Tolerances for residues of the insecticide 2,2-dichlorovinyl dimethyl phosphate are established for the following agricultural products: Cattle, (fat, cattle, meat, and meat-by-products); cucumbers; eggs; goats, (fat, meat, and meat-by-products); horses, (fat, meat, and meat-by-products); lettuce: milk; mushrooms; poultry, (fat, meat; and meat-by-products); radishes; raw agricultural commodities non-perishable; sheep, (fat, meat, and meat-by-products);and tomatoes.
[40 CFR 180.235 (7/1/97)]**PEER REVIEWED**

Pesticide chemicals that cause related pharmacological effects will be regarded as having an additive deleterious action. Where residues from two or more chemicals in the same class are present in or on a raw agricultural commodity the tolerance for the total of such residues shall be the same as that for the chemical having the lowest numerical tolerance in the class, unless a higher tolerance level is specifically provided for the combined residues by a regulation ... 2,2-Dichlorovinyl dimethyl phosphate is a member of the class of cholinesterase-inhibiting pesticides.
[40 CFR 180.3(e) (7/1/97)]**PEER REVIEWED**

The food additive 2,2-dichlorovinyl dimethyl phosphate may be present as a residue from application as an insecticide on packaged or bagged nonperishable processed food in an amount in such food not in excess of 0.5 ppm.
[40 CFR 185.1900 (7/1/97)]**PEER REVIEWED**

A Registration Standard was issued Sept 1987 for dichlorvos used as an insecticide.
[USEPA; Report on the Status of Chemicals in the Special Review Program and Registration Standards in the Reregisteration Program p. 2-6 (1989)]**PEER REVIEWED**

EPA is staying the effective date of an order which was published in 58 FR 59663 (11/10/93) regarding the revocation of the food additive regulation for dichlorvos. EPA received a petition to stay the March 10, 1994 effective date for the revocation of the food additive regulation 40 CFR 185.1900. EPA is staying the effective date in order to review the petition and determine whether to grant a stay, and if so, for what period.
[59 FR 11556 (3/11/94)]**PEER REVIEWED**

As the federal pesticide law FIFRA directs, EPA is conducting a comprehensive review of older pesticides to consider their health and environmental effects and make decisions about their future use. Under this pesticide reregistration program, EPA examines health and safety data for pesticide active ingredients initially registered before November 1, 1984, and determines whether they are eligible for reregistration. In addition, all pesticides must meet the new safety standard of the Food Quality Protection Act of 1996. Dichlorvos is found on List A, which contains most food use pesticides and consists of the 194 chemical cases (or 350 individual active ingredients) for which EPA issued registration standards prior to FIFRA, as amended in 1988. Case No: 0310; Pesticide type: insecticide; Case Status: OPP is reviewing data from the pesticide's producers regarding its human health and/or environmental effects, or OPP is determining the pesticide's eligibility for reregistration and developing the Reregistration Eligibility Decision (RED) document.; Active ingredient (AI): Dichlorvos; Data Call-in (DCI) Date(s): 09/20/91, 02/24/94, 11/01/94, 03/03/95, 10/13/95; AI Status: The producers of the pesticide has made commitments to conduct the studies and pay the fees required for reregistration, and are meeting those commitments in a timely manner.
[USEPA/OPP; Status of Pesticides in Registration, Reregistration and Special Review p.107 (Spring, 1998) EPA 738-R-98-002]**QC REVIEWED**

 

CERCLA Reportable Quantities:

Persons in charge of vessels or facilities are required to notify the National Response Center (NRC) immediately, when there is a release of this designated hazardous substance, in an amount equal to or greater than its reportable quantity of 10 lb or 4.54 kg. The toll free number of the NRC is (800) 424-8802; In the Washington D.C. metropolitan area (202) 426-2675. The rule for determining when notification is required is stated in 40 CFR 302.4 (section IV. D.3.b).
[40 CFR 302.4 (7/1/97)]**PEER REVIEWED**

This regulation establishes the list of extremely hazardous substances, threshold planning quantities, and facility notification responsibilities necessary for the development and implementation of State and local emergency response plans. Releases of CERCLA hazardous substances are subject to the release reporting requirement of CERCLA section 103, codified at 40 CFR part 302, in addition to the requirements of 40 CFR part 355. Dichlorovos is an extremely hazardous substance subject to reporting requirements when stored in amounts in excess of its threshold planning quantity of 1000 lbs.
[40 CFR 355 (7/1/97)]**PEER REVIEWED**

 

Atmospheric Standards:

Listed as a hazardous air pollutant (HAP) generally known or suspected to cause serious health problems. The Clean Air Act, as amended in 1990, directs EPA to set standards requiring major sources to sharply reduce routine emissions of toxic pollutants. EPA is required to establish and phase in specific performance based standards for all air emission sources that emit one or more of the listed pollutants. Dichlorvos is included on this list.
[Clean Air Act as amended in 1990, Sect. 112 (b) (1) Public Law 101-549 Nov. 15, 1990]**PEER REVIEWED**

 

Clean Water Act Requirements:

Designated as a hazardous substance under section 311(b)(2)(A) of the Federal Water Pollution Control Act and further regulated by the Clean Water Act Amendments of 1977 and 1978. These regulations apply to discharges of this substance.
[40 CFR 116.4 (7/1/91)] **QC REVIEWED**

 

State Drinking Water Guidelines:

(FL) FLORIDA 0.1 ug/l
[USEPA/Office of Water; Federal-State Toxicology and Risk Analysis Committee (FSTRAC). Summary of State and Federal Drinking Water Standards and Guidelines (11/93)] **QC REVIEWED**

 

FDA Requirements:

Oral dosage form new animal drugs not subject to certification: Conditions of use of 2,2-dichlorvinyl dimethyl phosphate are given for (1) swine; (2) dogs; (3) horses when administered in grain; horses when administered orally by syringe; (4) cats and puppies.
[21 CFR 520.600 (4/1/97)]**PEER REVIEWED**

Dichlorvos: Conditions of use: It is used in feed for swine as follows: Indications for use. For the removal and control of mature, immature, and/or fourth-stage larvae of the whipworm (Trichuris suis), nodular worm (Oesophagostomum spp), large roundworm (Ascaris suum) and the thick stomach worm (Ascarops strongylina) of the gastrointestinal tract. ... An aid in improving litter production efficiency by increasing pigs born alive, birth weights, survival to market, and rate of weight gain.
[21 CFR 558.205 (4/1/97)]**PEER REVIEWED**

A tolerance of 0.1 ppm is established for negligible residues of dichlorvos in the edible tissues of swine.
[21 CFR 556.180 (4/1/97)]**PEER REVIEWED**

 

Allowable Tolerances:

Tolerances for residues of the insecticide 2,2-dichlorovinyl dimethyl phosphate are established as follows (expressed in ppm; N = negligible residues): Cattle, fat: 0.02 (N); cattle, meat: 0.02 (N); cattle meat-by-products: 0.02 (N); cucumbers: (residues expressed as naled): 0.5; eggs: 0.05 (N); goats, fat: 0.02 (N); goats, meat: 0.02 (N); goats, meat-by-products: 0.02 (N); horses, fat: 0.02 (N); horses, meat 0.02: (N); horses, meat-by-products: 0.02 (N); lettuce (residues expressed as naled): 1.0; milk: 0.02 (N); mushrooms (residues expressed as naled): 0.5; poultry, fat: 0.05 (N); poultry, meat: 0.05 (N); poultry, meat-by-products: 0.05 (N); radishes: 0.5; raw agricultural commodities non-perishable, bulk stored regardless of fat content (post-harvest): 0.5; raw agricultural commodities, non-perishable, packaged or bagged, containing 6% fat or less (post-harvest): 0.5; raw agricultural commodities, non-perishable packaged or bagged, containing more than 6% fat (post-harvest): 2.0; sheep, fat: 0.02 (N); sheep, meat: 0.02 (N); sheep meat-by-products: 0.02 (N); tomatoes (pre- and post-harvest) (residues expressed as naled): 0.05.
[40 CFR 180.235 (7/1/97)]**PEER REVIEWED**

The food additive 2,2-dichlorovinyl dimethyl phosphate may be present as a residue from application as an insecticide on packaged or bagged nonperishable food in an amt in such food not in excess of 0.5 ppm.
[40 CFR 185.1900 (7/1/97)]**PEER REVIEWED**

A tolerance of 0.1 ppm is established for negligible residues of dichlorvos in the edible tissues of swine.
[21 CFR 556.180 (4/1/97)]**PEER REVIEWED**

 

Chemical/Physical Properties:

 

 

Molecular Formula:

C4-H7-Cl2-O4-P
**PEER REVIEWED**

 

Molecular Weight:

220.98
**PEER REVIEWED**

 

Color/Form:

Colorless to amber liquid /technical grade/
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium, 11 th ed., British Crop Protection Council, Surrey, England 1997 372]**PEER REVIEWED**

 

Odor:

Aromatic odor
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium, 11 th ed., British Crop Protection Council, Surrey, England 1997 372]**PEER REVIEWED**

Mild, chemical odor.
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 102]**PEER REVIEWED**

 

Boiling Point:

140 deg C @ 20 mm Hg
[Budavari, S. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Whitehouse Station, NJ: Merck and Co., Inc., 1996. 521]**PEER REVIEWED**

 

Corrosivity:

CORROSIVE TO IRON & MILD STEEL
[Worthing, C.R. and S.B. Walker (eds.). The Pesticide Manual - A World Compendium. 8th ed. Thornton Heath, UK: The British Crop Protection Council, 1987. 269]**PEER REVIEWED**

 

Density/Specific Gravity:

1.415 @ 25 deg C/4 deg C
[Budavari, S. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Whitehouse Station, NJ: Merck and Co., Inc., 1996. 521]**PEER REVIEWED**

 

Octanol/Water Partition Coefficient:

log Kow= 1.43
[Hansch, C., Leo, A., D. Hoekman. Exploring QSAR - Hydrophobic, Electronic, and Steric Constants. Washington, DC: American Chemical Society., 1995. 9]**PEER REVIEWED**

 

Solubilities:

Solubility in water: about 0.5 g/100 ml; in glycerol: about 0.5 g/100 ml
[Budavari, S. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Whitehouse Station, NJ: Merck and Co., Inc., 1996. 521]**PEER REVIEWED**

SOL IN CHLOROFORM, ACETONE
[Sunshine, I. (ed.). CRC Handbook of Analytical Toxicology. Cleveland: The Chemical Rubber Co., 1969. 508]**PEER REVIEWED**

SOLUBILITY IN KEROSENE 2 TO 3 G/KG
[Worthing, C.R. and S.B. Walker (eds.). The Pesticide Manual - A World Compendium. 8th ed. Thornton Heath, UK: The British Crop Protection Council, 1987. 269]**PEER REVIEWED**

MISCIBLE WITH MOST ... AEROSOL PROPELLANTS
[Worthing, C.R. and S.B. Walker (eds.). The Pesticide Manual - A World Compendium. 8th ed. Thornton Heath, UK: The British Crop Protection Council, 1987. 269]**PEER REVIEWED**

Water solubility: 10,000 mg/l @ 20 deg C
[Worthing, C.R., S.B. Walker (eds.). The Pesticide Manual - A World Compendium. 7th ed. Lavenham, Suffolk, Great Britain: The Lavenham Press Limited, 1983.]**PEER REVIEWED**

Completely miscible with aromatic hydrocarbons, chlorinated hydrocarbons, and alcohols; moderately soluble in diesel oil, kerosene, isoparaffinic hydrocarbons, and minerals oils
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium, 11 th ed., British Crop Protection Council, Surrey, England 1997 372]**PEER REVIEWED**

Miscible in dichloromethane, 2-propanol, toluene
[Farm Chemicals Handbook 1998. Willoughby, OH: Meister Publishing Co., 1998.,p. C-134]**PEER REVIEWED**

 

Spectral Properties:

INDEX OF REFRACTION: 1.451 @ 25 DEG C/D
[Budavari, S. (ed.). The Merck Index - Encyclopedia of Chemicals, Drugs and Biologicals. Rahway, NJ: Merck and Co., Inc., 1989. 485]**PEER REVIEWED**

Intense mass spectral peaks: 109 m/z (100%), 185 m/z (31%), 79 m/z (21%), 202 m/z (12%)
[Hites, R.A. Handbook of Mass Spectra of Environmental Contaminants. Boca Raton, FL: CRC Press Inc., 1985. 278]**PEER REVIEWED**

Intense mass spectral peaks: 145 m/z, 220 m/z
[Pfleger, K., H. Maurer and A. Weber. Mass Spectral and GC Data of Drugs, Poisons and their Metabolites. Parts I and II. Mass Spectra Indexes. Weinheim, FederalRepublic of Germany. 1985. 350]**PEER REVIEWED**

 

Vapor Pressure:

0.0158 mm Hg @ 25 deg C
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium, 11 th ed., British Crop Protection Council, Surrey, England 1997 372]**PEER REVIEWED**

 

Other Chemical/Physical Properties:

The air water partition coefficient is 5.0X10-3 for dichlorvos.
[Kawamoto K, Urano K; Chemosphere 18 (9-10): 1987-96 (1989)]**PEER REVIEWED**

The octanol water partition coefficient is 1.45X10+1 for dichlorvos.
[Kawamoto K, Urano K; Chemosphere 18 (9-10): 1987-96 (1989)]**PEER REVIEWED**

Slowly hydrolyzed in water and in acid media; rapidly hydrolyzed by alkalis to dimethyl hydrogen phosphate and dichloroacetaldehyde.
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium, 11 th ed., British Crop Protection Council, Surrey, England 1997 372]**PEER REVIEWED**

 

Chemical Safety & Handling:

 

 

Hazards Summary:

The major hazards encountered in the use and handling of dichlorvos stem from its toxicologic properties as an organophosphate pesticide. Direct contact with dichlorvos may cause burns to the skin and eyes. Systemic effects from skin absorption, ingestion, or inhalation range from depression of blood cholinesterase, dizziness, and confusion, to convulsions, coma, and death. The airborne level of dichlorvos reported by NIOSH to be immediately dangerous to life and health (IDLH) is 200 mg/cu m. The OSHA PEL and ACGIH TLV are both set at 1 mg/cu m, with an indication that skin contact be avoided. To avoid skin exposure, wear overalls made of tight fabric or polyvinyl chloride, gloves, rubber boots (some forms of rubber are attacked by dichlorvos), and a face shield or splash-proof goggles. To avoid inhalation wear a full facepiece supplied-air respirator or self-contained breathing apparatus. Clothing that becomes contaminated with dichlorvos should be promptly removed and any contaminated skin immediately washed with soap and water. Protect from exposure persons under 18 yr of age, expectant or nursing mothers, alcoholics, or those having diseases of the CNS, respiratory system, liver, kidney, or eyes. Dichlorvos will not ignite easily (flashpoint > 175 deg C open cup), but will burn with the possible release of toxic gases and vapors such as hydrogen chloride, phosphoric acid mist, and carbon monoxide. For small fires involving dichlorvos, extinguish with dry chemical, CO2, water spray, foam, and for large fires, use water spray, fog, or foam. Runoff from fire control water may give off poisonous gases or cause water polution and should, therefore, be diked for later disposal. Dichlorvos should be stored in a cool (< 80 deg F) and dry place (to avoid hydrolysis); away from strong acids and alkalis. In choosing an appropriate storage container, the fact that dichlorvos is corrosive to iron and mild steel should be considered. Containers of dichlorvos may be shipped by air, rail, road, water, and for both domestic and international compliance, should should be affixed with labels stating, "Keep Away From Food", and "Poison". For small spills of dichlorvos, absorb in vermiculite, dry sand or earth and collect for reclamation. Large land spills should be deposited in excavated pits, ponds, or other holding areas and the bulk material absorbed with fly ash or cement powder. Surface flow should be diked with sand bags or soil. Spills of dichlorvos in bodies of water, first may need to be treated with activated carbon, then the immobilized masses removed with mechanical dredges or lifts. Before permanent land disposal of dichlorvos, consult with environmental regulatory agencies.
**PEER REVIEWED**

 

DOT Emergency Guidelines:

Health: Highly toxic, may be fatal if inhaled, swallowed or absorbed through skin. Contact with molten substance may cause severe burns to skin and eyes. Avoid any skin contact. Effects of contact or inhalation may be delayed. Fire may produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may be corrosive and/or toxic and cause pollution.
[U.S. Department of Transportation. 1996 North American Emergency Response Guidebook. A Guidebook for First Responders During the Initial Phase of aHazardous Materials/Dangerous Goods Incident. U.S. Department of Transportation (U.S. DOT) Research and Special Programs Administration, Office of HazardousMaterials Initiatives and Training (DHM-50), Washington, D.C. (1996).,p. G-152]**PEER REVIEWED**

Fire or explosion: Combustible material: may burn but does not ignite readily. Containers may explode when heated. Runoff may pollute waterways. Substance may be transported in a molten form.
[U.S. Department of Transportation. 1996 North American Emergency Response Guidebook. A Guidebook for First Responders During the Initial Phase of aHazardous Materials/Dangerous Goods Incident. U.S. Department of Transportation (U.S. DOT) Research and Special Programs Administration, Office of HazardousMaterials Initiatives and Training (DHM-50), Washington, D.C. (1996).,p. G-152]**PEER REVIEWED**

Public safety: ... Isolate spill or leak area immediately for at least 25 to 50 meters (80 to 160 feet) in all directions. Keep unauthorized personnel away. Stay upwind. Keep out of low areas.
[U.S. Department of Transportation. 1996 North American Emergency Response Guidebook. A Guidebook for First Responders During the Initial Phase of aHazardous Materials/Dangerous Goods Incident. U.S. Department of Transportation (U.S. DOT) Research and Special Programs Administration, Office of HazardousMaterials Initiatives and Training (DHM-50), Washington, D.C. (1996).,p. G-152]**PEER REVIEWED**

Protective clothing: Wear positive pressure self-contained breathing apparatus (SCBA). Wear chemical protective clothing which is specifically recommended by the manufacturer. Structural firefighters' protective clothing is recommended for fire situations ONLY; it is not effective in spill situations.
[U.S. Department of Transportation. 1996 North American Emergency Response Guidebook. A Guidebook for First Responders During the Initial Phase of aHazardous Materials/Dangerous Goods Incident. U.S. Department of Transportation (U.S. DOT) Research and Special Programs Administration, Office of HazardousMaterials Initiatives and Training (DHM-50), Washington, D.C. (1996).,p. G-152]**PEER REVIEWED**

Evacuation: Spill: Fire: If tank, rail car or tank truck is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions.
[U.S. Department of Transportation. 1996 North American Emergency Response Guidebook. A Guidebook for First Responders During the Initial Phase of aHazardous Materials/Dangerous Goods Incident. U.S. Department of Transportation (U.S. DOT) Research and Special Programs Administration, Office of HazardousMaterials Initiatives and Training (DHM-50), Washington, D.C. (1996).,p. G-152]**PEER REVIEWED**

Fire: Small fires: Dry chemical, CO2 or water spray. Large fires: Water spray, fog or regular foam. Move containers from fire area if you can do it without risk. Dike fire control water for later disposal; do not scatter the material. Do not use straight streams. Fire involving tanks or car/trailer loads: Fight fire from maximum distance or use unmanned hose holders or monitor nozzles. Do not get water inside containers. Cool containers with flooding quantities of water until well after fire is out. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from the ends of tanks. For massive fire, use unmanned hose holders or monitor nozzles; if this is impossible, withdraw from area and let fire burn.
[U.S. Department of Transportation. 1996 North American Emergency Response Guidebook. A Guidebook for First Responders During the Initial Phase of aHazardous Materials/Dangerous Goods Incident. U.S. Department of Transportation (U.S. DOT) Research and Special Programs Administration, Office of HazardousMaterials Initiatives and Training (DHM-50), Washington, D.C. (1996).,p. G-152]**PEER REVIEWED**

Spill or leak: Do not touch damaged containers or spilled material unless wearing appropriate protective clothing. Stop leak if you can do it without risk. Prevent entry into waterways, sewers, basements or confined areas. Cover with plastic sheet to prevent spreading . Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers. DO NOT GET WATER INSIDE CONTAINERS.
[U.S. Department of Transportation. 1996 North American Emergency Response Guidebook. A Guidebook for First Responders During the Initial Phase of aHazardous Materials/Dangerous Goods Incident. U.S. Department of Transportation (U.S. DOT) Research and Special Programs Administration, Office of HazardousMaterials Initiatives and Training (DHM-50), Washington, D.C. (1996).,p. G-152]**PEER REVIEWED**

First aid: Move victim to fresh air. Call emergency medical care. Apply artificial respiration if victim is not breathing. Do not use mouth-to-mouth method if victim ingested or inhaled the substance; induce artificial respiration with the aid of a pocket mask equipped with a one-way valve or other proper respiratory medical device. Administer oxygen if breathing is difficult. Remove and isolate contaminated clothing and shoes. In case of contact with substance, immediately flush skin or eyes with running water for at least 20 minutes. For minor skin contact, avoid spreading material on unaffected skin. Keep victim warm and quiet. Effects of exposure (inhalation, ingestion or skin contact) to substance may be delayed. Ensure that medical personnel are aware of the material(s) involved, and take precautions to protect themselves.
[U.S. Department of Transportation. 1996 North American Emergency Response Guidebook. A Guidebook for First Responders During the Initial Phase of aHazardous Materials/Dangerous Goods Incident. U.S. Department of Transportation (U.S. DOT) Research and Special Programs Administration, Office of HazardousMaterials Initiatives and Training (DHM-50), Washington, D.C. (1996).,p. G-152]**PEER REVIEWED**

 

Skin, Eye and Respiratory Irritations:

Dichlorvos is not known to be an eye irritant.
[Mackison, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (eds.). NIOSH/OSHA - Occupational Health Guidelines for Chemical Hazards. DHHS(NIOSH) PublicationNo. 81-123 (3 VOLS). Washington, DC: U.S. Government Printing Office, Jan. 1981. 2]**PEER REVIEWED**

 

Fire Fighting Procedures:

If material is on fire or involved in a fire: Do not extinguish fire unless flow can be stopped; Use water in flooding quantities as fog; Solid streams of water may be ineffective; Cool all affected containers with flooding quantities of water; Apply water from as far a distance as possible; Use foam, carbon dioxide, or dry chemical. Keep run-off water out of sewers and water sources.
[Association of American Railroads. Emergency Handling of Hazardous Materials in Surface Transportation. Washington, D.C.: Assoc. of American Railroads,Hazardous Materials Systems (BOE), 1987. 247]**PEER REVIEWED**

Fire fighting: Self-contained breathing apparatus with a full facepiece operated in pressure demand or other positive pressure mode.
[Mackison, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (eds.). NIOSH/OSHA - Occupational Health Guidelines for Chemical Hazards. DHHS(NIOSH) PublicationNo. 81-123 (3 VOLS). Washington, DC: U.S. Government Printing Office, Jan. 1981. 5]**PEER REVIEWED**

 

Toxic Combustion Products:

Toxic gases and vapors (such as hydrogen chloride gas, phosphoric acid mist, and carbon monoxide) may be released in a fire involving dichlorvos.
[Mackison, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (eds.). NIOSH/OSHA - Occupational Health Guidelines for Chemical Hazards. DHHS(NIOSH) PublicationNo. 81-123 (3 VOLS). Washington, DC: U.S. Government Printing Office, Jan. 1981. 2]**PEER REVIEWED**

 

Hazardous Reactivities & Incompatibilities:

HYDROLYZES IN WATER
[Sunshine, I. (ed.). CRC Handbook of Analytical Toxicology. Cleveland: The Chemical Rubber Co., 1969. 509]**PEER REVIEWED**

Special precautions: Dichlorvos will attack some forms of plastics, rubber, and coatings.
[Mackison, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (eds.). NIOSH/OSHA - Occupational Health Guidelines for Chemical Hazards. DHHS(NIOSH) PublicationNo. 81-123 (3 VOLS). Washington, DC: U.S. Government Printing Office, Jan. 1981. 2]**PEER REVIEWED**

Strong acids, strong alkalis [Note: Corrosive to iron & mild steel].
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 102]**PEER REVIEWED**

 

Hazardous Decomposition:

READILY DECOMP IN STRONG ACID OR ALKALI
[Sunshine, I. (ed.). CRC Handbook of Analytical Toxicology. Cleveland: The Chemical Rubber Co., 1969. 509]**PEER REVIEWED**

Decomposition products may include toxic gases and vapors of hydrogen chloride gas, phosphoric acid mist, and carbon monoxide.
[Mackison, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (eds.). NIOSH/OSHA - Occupational Health Guidelines for Chemical Hazards. DHHS(NIOSH) PublicationNo. 81-123 (3 VOLS). Washington, DC: U.S. Government Printing Office, Jan. 1981. 2]**PEER REVIEWED**

 

Prior History of Accidents:

After a fire at the Sandoz Ltd. storehouse at Schweizerhalle, Switzerland, which stored pesticides, dichlorvos was released to Rhine River water.
[Capel PD et al; Environ Sci Technol 22: 992-7 (1988)]**PEER REVIEWED**

 

Immediately Dangerous to Life or Health:

100 mg/cu m
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 102]**PEER REVIEWED**

 

Protective Equipment & Clothing:

EMPLOYEES SHOULD BE PROVIDED WITH & REQUIRED TO USE IMPERVIOUS CLOTHING, GLOVES, FACE SHIELD (8-INCH MINIMUM), & OTHER APPROPRIATE PROTECTIVE CLOTHING NECESSARY TO PREVENT REPEATED OR PROLONGED SKIN CONTACT WITH DICHLORVOS. ... REQUIRED TO USE SPLASH-PROOF SAFETY GOGGLES WHERE LIQ ... MAY CONTACT EYES.
[Mackison, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (eds.). NIOSH/OSHA - Occupational Health Guidelines for Chemical Hazards. DHHS(NIOSH) PublicationNo. 81-123 (3 VOLS). Washington, DC: U.S. Government Printing Office, Jan. 1981. 2]**PEER REVIEWED**

Respiratory protection from dichlorvos is as follows: 10 mg/cu m or less: Any supplied-air respirator or any self-contained breathing apparatus; 50 mg/cu m or less: Any supplied-air respirator with a full facepiece, helmet or hood or any self-contained breathing apparatus with a full facepiece; 200 mg/cu m or less; A Type-C supplied-air respirator operated in pressure-demand or other positive pressure or continuous-flow mode; Greater than 200 mg/cu m or entry or escape from unknown concentrations; A combination respirator which includes a Type-C supplied-air respirator with a full facepiece operated in pressure-demand or other positive pressure or continuous-flow mode and an auxiliary self-contained breathing apparatus operated in pressure-demand or other positive pressure mode; Escape: Any gas mask providing protection against organic vapors and particulates including pesticide respirations which meet the requirements of this class or any self-contained breathing apparatus. Use of supplied-air suits may be necessary to prevent skin contact while providing respiratory protection from airborne concentrations of dichlorvos. ... Where supplied-air suits are used above a concentration of 200 mg/cu m, an auxiliary self-contained breathing apparatus operated in positive pressure mode should also be worn.
[Mackison, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (eds.). NIOSH/OSHA - Occupational Health Guidelines for Chemical Hazards. DHHS(NIOSH) PublicationNo. 81-123 (3 VOLS). Washington, DC: U.S. Government Printing Office, Jan. 1981. 5]**PEER REVIEWED**

WORKERS HANDLING AND APPLYING ORGANOPHOSPHORUS PESTICIDES ... MUST BE GIVEN PERSONAL PROTECTIVE EQUIPMENT COMPRISING OVERALLS MADE OF A TIGHT FABRIC OR POLYVINYL CHLORIDE, GLOVES AND RUBBER BOOTS. THEY MUST WEAR A RESPIRATOR WITH AN ACTIVATED-CARBON GAS FILTER CARTRIDGE AFFORDING PROTECTION FOR A DETERMINED NUMBER OF WORKING HOURS. THE EYES SHOULD BE PROTECTED BY GOGGLES. ... /ORGANOPHOSPHORUS PESTICIDES/
[International Labour Office. Encyclopedia of Occupational Health and Safety. Vols. I&II. Geneva, Switzerland: International Labour Office, 1983. 1645]**PEER REVIEWED**

Wear appropriate personal protective clothing to prevent skin contact.
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 103]**PEER REVIEWED**

Wear appropriate eye protection to prevent eye contact.
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 103]**PEER REVIEWED**

Recommendations for respirator selection. Max concn for use: 10 mg/cu m. Respirator Class(es): Any supplied-air respirator.
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 103]**PEER REVIEWED**

Recommendations for respirator selection. Max concn for use: 25 mg/cu m. Respirator Class(es): Any supplied-air respirator operated in a continuous flow mode.
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 103]**PEER REVIEWED**

Recommendations for respirator selection. Max concn for use: 50 mg/cu m. Respirator Class(es): Any supplied-air respirator that has a tight-fitting facepiece and is operated in a continuous-flow mode. Any self-contained breathing apparatus with a full facepiece. Any supplied-air respirator with a full facepiece.
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 103]**PEER REVIEWED**

Recommendations for respirator selection. Max concn for use: 100 mg/cu m. Respirator Class(es): Any supplied-air respirator operated in a pressure-demand or other positive-pressure mode.
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 103]**PEER REVIEWED**

Recommendations for respirator selection. Condition: Emergency or planned entry into unknown concn or IDLH conditions: Respirator Class(es): Any self-contained breathing apparatus that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode. Any supplied-air respirator that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode in combination with an auxiliary self-contained breathing apparatus operated in pressure-demand or other positive-pressure mode.
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 103]**PEER REVIEWED**

Recommendations for respirator selection. Condition: Escape from suddenly occurring respiratory hazards: Respirator Class(es): Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted organic vapor canister having a high-efficiency particulate filter. Any appropriate escape-type, self-contained breathing apparatus.
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 103]**PEER REVIEWED**

PRECAUTIONS FOR "CARCINOGENS": ... Dispensers of liq detergent /should be available./ ... Safety pipettes should be used for all pipetting. ... In animal laboratory, personnel should ... wear protective suits (preferably disposable, one-piece & close-fitting at ankles & wrists), gloves, hair covering & overshoes. ... In chemical laboratory, gloves & gowns should always be worn ... however, gloves should not be assumed to provide full protection. Carefully fitted masks or respirators may be necessary when working with particulates or gases, & disposable plastic aprons might provide addnl protection. ... Gowns ... /should be/ of distinctive color, this is a reminder that they are not to be worn outside the laboratory. /Chemical Carcinogens/
[Montesano, R., H. Bartsch, E.Boyland, G. Della Porta, L. Fishbein, R. A. Griesemer, A.B. Swan, L. Tomatis, and W. Davis (eds.). Handling Chemical Carcinogens in the Laboratory:Problems of Safety. IARC Scientific Publications No. 33. Lyon, France: International Agency for Research on Cancer, 1979. 8]**PEER REVIEWED**

 

Preventive Measures:

Do not consume alcohol before, or during spraying.
[Hartley, D. and H. Kidd (eds.). The Agrochemicals Handbook. Old Woking, Surrey, United Kingdom: Royal Society of Chemistry/Unwin Brothers Ltd., 1983.,p. A142/Oct 83]**PEER REVIEWED**

In case of spill notify local health and wildlife officials. Notify operators of nearby water intakes.
[U.S. Coast Guard, Department of Transportation. CHRIS - Hazardous Chemical Data. Volume II. Washington, D.C.: U.S. Government Printing Office, 1984-5.]**PEER REVIEWED**

If material is not on fire and not involved in a fire: Keep sparks, flames, and other sources of ignition away; Keep material out of water sources and sewers; Build dikes to contain flow as necessary; Attempt to stop leak if without hazard; Use water spray to knock-down vapors.
[Association of American Railroads. Emergency Handling of Hazardous Materials in Surface Transportation. Washington, D.C.: Assoc. of American Railroads,Hazardous Materials Systems (BOE), 1987. 247]**PEER REVIEWED**

Avoid breathing vapors. Keep upwind. Do not handle broken packages without protective equipment. Wash away any material which may have contacted the body with copious amounts of water, or soap and water.
[Association of American Railroads. Emergency Handling of Hazardous Materials in Surface Transportation. Washington, D.C.: Assoc. of American Railroads,Hazardous Materials Systems (BOE), 1987. 247]**PEER REVIEWED**

Good industrial hygiene practices recommend that engineering controls be used to reduce environmental concentrations to the permissible level, however, there are some exceptions where respirators may be used to control exposure. Respirators may be used when engineering and work practice controls are not technically feasible, when such controls are in the process of being installed, or when they fail and need to be supplemented. Respirators may also be used for operations which require entry into tanks or closed vessels, and in emergency situations. If the use of respirators is necessary, the only respirators permitted are those that have been approved by the Mine Safety and Health Administration (formerly Mining Enforcement and Safety Administration) or by the National Institute for Occupational Safety and Health. In addition to respirator selection, a complete respiratory protection program should be instituted which includes regular training, maintenance, inspection, cleaning, and evaluation.
[Mackison, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (eds.). NIOSH/OSHA - Occupational Health Guidelines for Chemical Hazards. DHHS(NIOSH) PublicationNo. 81-123 (3 VOLS). Washington, DC: U.S. Government Printing Office, Jan. 1981. 3]**PEER REVIEWED**

Clothing contaminated with dichlorvos should be placed in closed containers for storage until it can be discarded or until provision is made for the removal of dichlorvos from the clothing. If the clothing is to be laundered or otherwise cleaned to remove the dichlorvos, the person performing the operation should be informed of dichlorvos's hazardous properties.
[Mackison, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (eds.). NIOSH/OSHA - Occupational Health Guidelines for Chemical Hazards. DHHS(NIOSH) PublicationNo. 81-123 (3 VOLS). Washington, DC: U.S. Government Printing Office, Jan. 1981. 3]**PEER REVIEWED**

Non-impervious clothing which becomes contaminated with dichlorvos should be removed immediately and not reworn until the dichlorvos is removed from the clothing.
[Mackison, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (eds.). NIOSH/OSHA - Occupational Health Guidelines for Chemical Hazards. DHHS(NIOSH) PublicationNo. 81-123 (3 VOLS). Washington, DC: U.S. Government Printing Office, Jan. 1981. 3]**PEER REVIEWED**

Skin that becomes contaminated with dichlorvos should be immediately washed or showered with soap or mild detergent and water to remove any dichlorvos. Employees who handle dichlorvos should wash their hands thoroughly with soap and mild detergent and water before eating, smoking, or using toilet facilities.
[Mackison, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (eds.). NIOSH/OSHA - Occupational Health Guidelines for Chemical Hazards. DHHS(NIOSH) PublicationNo. 81-123 (3 VOLS). Washington, DC: U.S. Government Printing Office, Jan. 1981. 3]**PEER REVIEWED**

CONTAINERS ... SHOULD BE CLEANED WITH A SUSPENSION OF BLEACHING POWDER IN WATER OR WITH OTHER ALKALINE SOLN AFTER SOAKING FOR 24 HR AND THEN BE RINSED WITH HOT WATER. /ORGANOPHOSPHORUS PESTICIDES/
[International Labour Office. Encyclopedia of Occupational Health and Safety. Vols. I&II. Geneva, Switzerland: International Labour Office, 1983. 1024]**PEER REVIEWED**

THE STRICT OBSERVANCE OF HYGIENE RULES- NO SMOKING AND NO FOOD INTAKE DURING WORK, THOROUGH WASHING WITH SOAP AFTER WORK, CHANGING PROTECTIVE CLOTHING BEFORE GOING HOME- IS OF THE UTMOST IMPORTANCE. /ORGANOPHOSPHORUS PESTICIDES/
[International Labour Office. Encyclopedia of Occupational Health and Safety. Vols. I&II. Geneva, Switzerland: International Labour Office, 1983. 1645]**PEER REVIEWED**

THE PROTECTIVE CLOTHING SHOULD BE KEPT IN SEPARATE PLACES WHERE IT CANNOT BE CONTAMINATED WITH TOXIC CHEMICALS. IT SHOULD BE FORBIDDEN TO KEEP THIS CLOTHING IN LIVING QUARTERS. PROTECTIVE CLOTHING MUST BE WASHED AT LEAST ONCE A WEEK AND EACH TIME IT IS CONTAMINATED WITH PESTICIDES. BEFORE WASHING THE CLOTHING SHOULD BE SOAKED FOR SEVERAL HOURS IN A CALCIUM CARBONATE SOLUTION. /PESTICIDES/
[International Labour Office. Encyclopedia of Occupational Health and Safety. Vols. I&II. Geneva, Switzerland: International Labour Office, 1983. 1645]**PEER REVIEWED**

Smoking, eating, and drinking before washing should be absolutely prohibited when any pesticide ... is being handled or used. /Pesticides/
[International Labour Office. Encyclopedia of Occupational Health and Safety. Vols. I&II. Geneva, Switzerland: International Labour Office, 1983. 1619]**PEER REVIEWED**

Contact lenses should not be worn when working with this chemical.
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 103]**PEER REVIEWED**

SRP: The scientific literature for the use of contact lenses in industry is conflicting. The benefit or detrimental effects of wearing contact lenses depend not only upon the substance, but also on factors including the form of the substance, characteristics and duration of the exposure, the uses of other eye protection equipment, and the hygiene of the lenses. However, there may be individual substances whose irritating or corrosive properties are such that the wearing of contact lenses would be harmful to the eye. In those specific cases, contact lenses should not be worn. In any event, the usual eye protection equipment should be worn even when contact lenses are in place.
**PEER REVIEWED**

The worker should immediately wash the skin when it becomes contaminated.
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 103]**PEER REVIEWED**

Work clothing that becomes wet or significantly contaminated should be removed and replaced.
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 103]**PEER REVIEWED**

PRECAUTIONS FOR "CARCINOGENS": Smoking, drinking, eating, storage of food or of food & beverage containers or utensils, & the application of cosmetics should be prohibited in any laboratory. All personnel should remove gloves, if worn, after completion of procedures in which carcinogens have been used. They should ... wash ... hands, preferably using dispensers of liq detergent, & rinse ... thoroughly. Consideration should be given to appropriate methods for cleaning the skin, depending on nature of the contaminant. No standard procedure can be recommended, but the use of organic solvents should be avoided. Safety pipettes should be used for all pipetting. /Chemical Carcinogens/
[Montesano, R., H. Bartsch, E.Boyland, G. Della Porta, L. Fishbein, R. A. Griesemer, A.B. Swan, L. Tomatis, and W. Davis (eds.). Handling Chemical Carcinogens in the Laboratory:Problems of Safety. IARC Scientific Publications No. 33. Lyon, France: International Agency for Research on Cancer, 1979. 8]**PEER REVIEWED**

PRECAUTIONS FOR "CARCINOGENS": In animal laboratory, personnel should remove their outdoor clothes & wear protective suits (preferably disposable, one-piece & close-fitting at ankles & wrists), gloves, hair covering & overshoes. ... Clothing should be changed daily but ... discarded immediately if obvious contamination occurs ... /also,/ workers should shower immediately. In chemical laboratory, gloves & gowns should always be worn ... however, gloves should not be assumed to provide full protection. Carefully fitted masks or respirators may be necessary when working with particulates or gases, & disposable plastic aprons might provide addnl protection. If gowns are of distinctive color, this is a reminder that they should not be worn outside of lab. /Chemical Carcinogens/
[Montesano, R., H. Bartsch, E.Boyland, G. Della Porta, L. Fishbein, R. A. Griesemer, A.B. Swan, L. Tomatis, and W. Davis (eds.). Handling Chemical Carcinogens in the Laboratory:Problems of Safety. IARC Scientific Publications No. 33. Lyon, France: International Agency for Research on Cancer, 1979. 8]**PEER REVIEWED**

PRECAUTIONS FOR "CARCINOGENS": ... Operations connected with synth & purification ... should be carried out under well-ventilated hood. Analytical procedures ... should be carried out with care & vapors evolved during ... procedures should be removed. ... Expert advice should be obtained before existing fume cupboards are used ... & when new fume cupboards are installed. It is desirable that there be means for decreasing the rate of air extraction, so that carcinogenic powders can be handled without ... powder being blown around the hood. Glove boxes should be kept under negative air pressure. Air changes should be adequate, so that concn of vapors of volatile carcinogens will not occur. /Chemical Carcinogens/
[Montesano, R., H. Bartsch, E.Boyland, G. Della Porta, L. Fishbein, R. A. Griesemer, A.B. Swan, L. Tomatis, and W. Davis (eds.). Handling Chemical Carcinogens in the Laboratory:Problems of Safety. IARC Scientific Publications No. 33. Lyon, France: International Agency for Research on Cancer, 1979. 8]**PEER REVIEWED**

PRECAUTIONS FOR "CARCINOGENS": Vertical laminar-flow biological safety cabinets may be used for containment of in vitro procedures ... provided that the exhaust air flow is sufficient to provide an inward air flow at the face opening of the cabinet, & contaminated air plenums that are under positive pressure are leak-tight. Horizontal laminar-flow hoods or safety cabinets, where filtered air is blown across the working area towards the operator, should never be used ... Each cabinet or fume cupboard to be used ... should be tested before work is begun (eg, with fume bomb) & label fixed to it, giving date of test & avg air-flow measured. This test should be repeated periodically & after any structural changes. /Chemical Carcinogens/
[Montesano, R., H. Bartsch, E.Boyland, G. Della Porta, L. Fishbein, R. A. Griesemer, A.B. Swan, L. Tomatis, and W. Davis (eds.). Handling Chemical Carcinogens in the Laboratory:Problems of Safety. IARC Scientific Publications No. 33. Lyon, France: International Agency for Research on Cancer, 1979. 9]**PEER REVIEWED**

PRECAUTIONS FOR "CARCINOGENS": Principles that apply to chem or biochem lab also apply to microbiological & cell-culture labs ... Special consideration should be given to route of admin. ... Safest method of administering volatile carcinogen is by injection of a soln. Admin by topical application, gavage, or intratracheal instillation should be performed under hood. If chem will be exhaled, animals should be kept under hood during this period. Inhalation exposure requires special equipment. ... Unless specifically required, routes of admin other than in the diet should be used. Mixing of carcinogen in diet should be carried out in sealed mixers under fume hood, from which the exhaust is fitted with an efficient particulate filter. Techniques for cleaning mixer & hood should be devised before expt begun. When mixing diets, special protective clothing &, possibly, respirators may be required. /Chemical Carcinogens/
[Montesano, R., H. Bartsch, E.Boyland, G. Della Porta, L. Fishbein, R. A. Griesemer, A.B. Swan, L. Tomatis, and W. Davis (eds.). Handling Chemical Carcinogens in the Laboratory:Problems of Safety. IARC Scientific Publications No. 33. Lyon, France: International Agency for Research on Cancer, 1979. 9]**PEER REVIEWED**

PRECAUTIONS FOR "CARCINOGENS": When ... admin in diet or applied to skin, animals should be kept in cages with solid bottoms & sides & fitted with a filter top. When volatile carcinogens are given, filter tops should not be used. Cages which have been used to house animals that received carcinogens should be decontaminated. Cage-cleaning facilities should be installed in area in which carcinogens are being used, to avoid moving of ... contaminated /cages/. It is difficult to ensure that cages are decontaminated, & monitoring methods are necessary. Situations may exist in which the use of disposable cages should be recommended, depending on type & amt of carcinogen & efficiency with which it can be removed. /Chemical Carcinogens/
[Montesano, R., H. Bartsch, E.Boyland, G. Della Porta, L. Fishbein, R. A. Griesemer, A.B. Swan, L. Tomatis, and W. Davis (eds.). Handling Chemical Carcinogens in the Laboratory:Problems of Safety. IARC Scientific Publications No. 33. Lyon, France: International Agency for Research on Cancer, 1979. 10]**PEER REVIEWED**

PRECAUTIONS FOR "CARCINOGENS": To eliminate risk that ... contamination in lab could build up during conduct of expt, periodic checks should be carried out on lab atmospheres, surfaces, such as walls, floors & benches, & ... interior of fume hoods & airducts. As well as regular monitoring, check must be carried out after cleaning-up of spillage. Sensitive methods are required when testing lab atmospheres. ... Methods ... should ... where possible, be simple & sensitive. /Chemical Carcinogens/
[Montesano, R., H. Bartsch, E.Boyland, G. Della Porta, L. Fishbein, R. A. Griesemer, A.B. Swan, L. Tomatis, and W. Davis (eds.). Handling Chemical Carcinogens in the Laboratory:Problems of Safety. IARC Scientific Publications No. 33. Lyon, France: International Agency for Research on Cancer, 1979. 10]**PEER REVIEWED**

PRECAUTIONS FOR "CARCINOGENS": Rooms in which obvious contamination has occurred, such as spillage, should be decontaminated by lab personnel engaged in expt. Design of expt should ... avoid contamination of permanent equipment. ... Procedures should ensure that maintenance workers are not exposed to carcinogens. ... Particular care should be taken to avoid contamination of drains or ventilation ducts. In cleaning labs, procedures should be used which do not produce aerosols or dispersal of dust, ie, wet mop or vacuum cleaner equipped with high-efficiency particulate filter on exhaust, which are avail commercially, should be used. Sweeping, brushing & use of dry dusters or mops should be prohibited. Grossly contaminated cleaning materials should not be re-used ... If gowns or towels are contaminated, they should not be sent to laundry, but ... decontaminated or burnt, to avoid any hazard to laundry personnel. /Chemical Carcinogens/
[Montesano, R., H. Bartsch, E.Boyland, G. Della Porta, L. Fishbein, R. A. Griesemer, A.B. Swan, L. Tomatis, and W. Davis (eds.). Handling Chemical Carcinogens in the Laboratory:Problems of Safety. IARC Scientific Publications No. 33. Lyon, France: International Agency for Research on Cancer, 1979. 10]**PEER REVIEWED**

PRECAUTIONS FOR "CARCINOGENS": Doors leading into areas where carcinogens are used ... should be marked distinctively with appropriate labels. Access ... limited to persons involved in expt. ... A prominently displayed notice should give the name of the Scientific Investigator or other person who can advise in an emergency & who can inform others (such as firemen) on the handling of carcinogenic substances. /Chemical Carcinogens/
[Montesano, R., H. Bartsch, E.Boyland, G. Della Porta, L. Fishbein, R. A. Griesemer, A.B. Swan, L. Tomatis, and W. Davis (eds.). Handling Chemical Carcinogens in the Laboratory:Problems of Safety. IARC Scientific Publications No. 33. Lyon, France: International Agency for Research on Cancer, 1979. 11]**PEER REVIEWED**

SRP: Contaminated protective clothing should be segregated in such a manner so that there is no direct personal contact by personnel who handle, dispose, or clean the clothing. Quality assurance to ascertain the completeness of the cleaning procedures should be implemented before the decontaminated protective clothing is returned for reuse by the workers. Contaminated clothing should not be taken home at end of shift, but should remain at employee's place of work for cleaning.
**PEER REVIEWED**

 

Stability/Shelf Life:

STABLE TO HEAT
[Worthing, C.R. and S.B. Walker (eds.). The Pesticide Manual - A World Compendium. 8th ed. Thornton Heath, UK: The British Crop Protection Council, 1987. 269]**PEER REVIEWED**

 

Shipment Methods and Regulations:

No person may /transport,/ offer or accept a hazardous material for transportation in commerce unless that person is registered in conformance ... and the hazardous material is properly classed, described, packaged, marked, labeled, and in condition for shipment as required or authorized by ... /the hazardous materials regulations (49 CFR 171-177)./
[49 CFR 171.2 (7/1/96)]**PEER REVIEWED**

The International Air Transport Association (IATA) Dangerous Goods Regulations are published by the IATA Dangerous Goods Board pursuant to IATA Resolutions 618 and 619 and constitute a manual of industry carrier regulations to be followed by all IATA Member airlines when transporting hazardous materials.
[IATA. Dangerous Goods Regulations. 38th ed. Montreal, Canada and Geneva, Switzerland: International Air Transport Association, Dangerous Goods Board, January, 1997. 190]**PEER REVIEWED**

The International Maritime Dangerous Goods Code lays down basic principles for transporting hazardous chemicals. Detailed recommendations for individual substances and a number of recommendations for good practice are included in the classes dealing with such substances. A general index of technical names has also been compiled. This index should always be consulted when attempting to locate the appropriate procedures to be used when shipping any substance or article.
[IMDG; International Maritime Dangerous Goods Code; International Maritime Organization p.3097-1, 6193-5 (1988)]**PEER REVIEWED**

PRECAUTIONS FOR "CARCINOGENS": Procurement ... of unduly large amt ... should be avoided. To avoid spilling, carcinogens should be transported in securely sealed glass bottles or ampoules, which should themselves be placed inside strong screw-cap or snap-top container that will not open when dropped & will resist attack from the carcinogen. Both bottle & the outside container should be appropriately labelled. ... National post offices, railway companies, road haulage companies & airlines have regulations governing transport of hazardous materials. These authorities should be consulted before ... material is shipped. /Chemical Carcinogens/
[Montesano, R., H. Bartsch, E.Boyland, G. Della Porta, L. Fishbein, R. A. Griesemer, A.B. Swan, L. Tomatis, and W. Davis (eds.). Handling Chemical Carcinogens in the Laboratory:Problems of Safety. IARC Scientific Publications No. 33. Lyon, France: International Agency for Research on Cancer, 1979. 13]**PEER REVIEWED**

PRECAUTIONS FOR "CARCINOGENS": When no regulations exist, the following procedure must be adopted. The carcinogen should be enclosed in a securely sealed, watertight container (primary container), which should be enclosed in a second, unbreakable, leakproof container that will withstand chem attack from the carcinogen (secondary container). The space between primary & secondary container should be filled with absorbent material, which would withstand chem attack from the carcinogen & is sufficient to absorb the entire contents of the primary container in the event of breakage or leakage. Each secondary container should then be enclosed in a strong outer box. The space between the secondary container & the outer box should be filled with an appropriate quantity of shock-absorbent material. Sender should use fastest & most secure form of transport & notify recipient of its departure. If parcel is not received when expected, carrier should be informed so that immediate effort can be made to find it. Traffic schedules should be consulted to avoid ... arrival on weekend or holiday ... /Chemical Carcinogens/
[Montesano, R., H. Bartsch, E.Boyland, G. Della Porta, L. Fishbein, R. A. Griesemer, A.B. Swan, L. Tomatis, and W. Davis (eds.). Handling Chemical Carcinogens in the Laboratory:Problems of Safety. IARC Scientific Publications No. 33. Lyon, France: International Agency for Research on Cancer, 1979. 13]**PEER REVIEWED**

 

Storage Conditions:

IT MUST BE STORED @ TEMP BELOW 80 DEG F TO ASSURE PROPER SHELF LIFE.
[Booth, N.H., L.E. McDonald (eds.). Veterinary Pharmacology and Therapeutics. 5th ed. Ames, Iowa: Iowa State University Press, 1982. 830]**PEER REVIEWED**

Store in origional container, preferably in a locked area, away from children, food, feed.
[Farm Chemicals Handbook 1991. Willoughby, OH: Meister, 1991.,p. C-96]**PEER REVIEWED**

PRECAUTIONS FOR "CARCINOGENS": Storage site should be as close as practical to lab in which carcinogens are to be used, so that only small quantities required for ... expt need to be carried. Carcinogens should be kept in only one section of cupboard, an explosion-proof refrigerator or freezer (depending on chemicophysical properties ...) that bears appropriate label. An inventory ... should be kept, showing quantity of carcinogen & date it was acquired ... Facilities for dispensing ... should be contiguous to storage area. /Chemical Carcinogens/
[Montesano, R., H. Bartsch, E.Boyland, G. Della Porta, L. Fishbein, R. A. Griesemer, A.B. Swan, L. Tomatis, and W. Davis (eds.). Handling Chemical Carcinogens in the Laboratory:Problems of Safety. IARC Scientific Publications No. 33. Lyon, France: International Agency for Research on Cancer, 1979. 13]**PEER REVIEWED**

 

Cleanup Methods:

Land spill: Dig a pit, pond, lagoon, holding area to contain liquid or solid material. /SRP: If time permits, pits, ponds, lagoons, soak holes, or holding areas should be sealed with an impermeable flexible membrane liner./ Dike surface flow using soil, sand bags, foamed polyurethane, or foamed concrete. Absorb bulk liquid with fly ash, or cement powder.
[Association of American Railroads. Emergency Handling of Hazardous Materials in Surface Transportation. Washington, D.C.: Assoc. of American Railroads,Hazardous Materials Systems (BOE), 1987. 247]**PEER REVIEWED**

Water spill: If dissolved, apply activated carbon at ten times the spilled amount in region of 10 ppm or greater concn. Use mechanical dredges, or lifts to remove immobilized masses of pollutants and precipitates.
[Association of American Railroads. Emergency Handling of Hazardous Materials in Surface Transportation. Washington, D.C.: Assoc. of American Railroads,Hazardous Materials Systems (BOE), 1987. 247]**PEER REVIEWED**

Air spill: Apply water spray or mist to knock down vapors.
[Association of American Railroads. Emergency Handling of Hazardous Materials in Surface Transportation. Washington, D.C.: Assoc. of American Railroads,Hazardous Materials Systems (BOE), 1987. 247]**PEER REVIEWED**

Ventilate area of spill or leak. Collect for reclamation or absorb in vermiculite, dry sand, earth, or similar material.
[Mackison, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (eds.). NIOSH/OSHA - Occupational Health Guidelines for Chemical Hazards. DHHS(NIOSH) PublicationNo. 81-123 (3 VOLS). Washington, DC: U.S. Government Printing Office, Jan. 1981. 4]**PEER REVIEWED**

PRECAUTIONS FOR "CARCINOGENS": A high-efficiency particulate arrestor (HEPA) or charcoal filters can be used to minimize amt of carcinogen in exhausted air ventilated safety cabinets, lab hoods, glove boxes or animal rooms ... Filter housing that is designed so that used filters can be transferred into plastic bag without contaminating maintenance staff is avail commercially. Filters should be placed in plastic bags immediately after removal ... The plastic bag should be sealed immediately ... The sealed bag should be labelled properly ... Waste liquids ... should be placed or collected in proper containers for disposal. The lid should be secured & the bottles properly labelled. Once filled, bottles should be placed in plastic bag, so that outer surface ... is not contaminated ... The plastic bag should also be sealed & labelled. ... Broken glassware ... should be decontaminated by solvent extraction, by chemical destruction, or in specially designed incinerators. /Chemical Carcinogens/
[Montesano, R., H. Bartsch, E.Boyland, G. Della Porta, L. Fishbein, R. A. Griesemer, A.B. Swan, L. Tomatis, and W. Davis (eds.). Handling Chemical Carcinogens in the Laboratory:Problems of Safety. IARC Scientific Publications No. 33. Lyon, France: International Agency for Research on Cancer, 1979. 15]**PEER REVIEWED**

 

Disposal Methods:

SRP: At the time of review, criteria for land treatment or burial (sanitary landfill) disposal practices are subject to significant revision. Prior to implementing land disposal of waste residue (including waste sludge), consult with environmental regulatory agencies for guidance on acceptable disposal practices.
**PEER REVIEWED**

Treat dichlorvos by alkali, (64% disappearance in Zahn at pH 8.7) mix the product with a portion of soil rich in organic matter before burying. Recommendable methods: Incineration, hydrolysis, & landfill. Peer-review: Adsorb residues on sawdust and incinerate @ high temp in a unit with effluent gas scrubbing. (Peer-review conclusions of an IRPTC expert consultation (May 1985))
[United Nations. Treatment and Disposal Methods for Waste Chemicals (IRPTC File). Data Profile Series No. 5. Geneva, Switzerland: United Nations Environmental Programme, Dec. 1985. 235]**PEER REVIEWED**

PRECAUTIONS FOR "CARCINOGENS": There is no universal method of disposal that has been proved satisfactory for all carcinogenic compounds & specific methods of chem destruction ... published have not been tested on all kinds of carcinogen-containing waste. ... summary of avail methods & recommendations ... /given/ must be treated as guide only. /Chemical Carcinogens/
[Montesano, R., H. Bartsch, E.Boyland, G. Della Porta, L. Fishbein, R. A. Griesemer, A.B. Swan, L. Tomatis, and W. Davis (eds.). Handling Chemical Carcinogens in the Laboratory:Problems of Safety. IARC Scientific Publications No. 33. Lyon, France: International Agency for Research on Cancer, 1979. 14]**PEER REVIEWED**

PRECAUTIONS FOR "CARCINOGENS": ... Incineration may be only feasible method for disposal of contaminated laboratory waste from biological expt. However, not all incinerators are suitable for this purpose. The most efficient type ... is probably the gas-fired type, in which a first-stage combustion with a less than stoichiometric air:fuel ratio is followed by a second stage with excess air. Some ... are designed to accept ... aqueous & organic-solvent solutions, otherwise it is necessary ... to absorb soln onto suitable combustible material, such as sawdust. Alternatively, chem destruction may be used, esp when small quantities ... are to be destroyed in laboratory. /Chemical Carcinogens/
[Montesano, R., H. Bartsch, E.Boyland, G. Della Porta, L. Fishbein, R. A. Griesemer, A.B. Swan, L. Tomatis, and W. Davis (eds.). Handling Chemical Carcinogens in the Laboratory:Problems of Safety. IARC Scientific Publications No. 33. Lyon, France: International Agency for Research on Cancer, 1979. 15]**PEER REVIEWED**

PRECAUTIONS FOR "CARCINOGENS": HEPA (high-efficiency particulate arrestor) filters ... can be disposed of by incineration. For spent charcoal filters, the adsorbed material can be stripped off at high temp & carcinogenic wastes generated by this treatment conducted to & burned in an incinerator. ... LIQUID WASTE: ... Disposal should be carried out by incineration at temp that ... ensure complete combustion. SOLID WASTE: Carcasses of lab animals, cage litter & misc solid wastes ... should be disposed of by incineration at temp high enough to ensure destruction of chem carcinogens or their metabolites. /Chemical Carcinogens/
[Montesano, R., H. Bartsch, E.Boyland, G. Della Porta, L. Fishbein, R. A. Griesemer, A.B. Swan, L. Tomatis, and W. Davis (eds.). Handling Chemical Carcinogens in the Laboratory:Problems of Safety. IARC Scientific Publications No. 33. Lyon, France: International Agency for Research on Cancer, 1979. 15]**PEER REVIEWED**

PRECAUTIONS FOR "CARCINOGENS": ... Small quantities of ... some carcinogens can be destroyed using chem reactions ... but no general rules can be given. ... As a general technique ... treatment with sodium dichromate in strong sulfuric acid can be used. The time necessary for destruction ... is seldom known ... but 1-2 days is generally considered sufficient when freshly prepd reagent is used. ... Carcinogens that are easily oxidizable can be destroyed with milder oxidative agents, such as saturated soln of potassium permanganate in acetone, which appears to be a suitable agent for destruction of hydrazines or of compounds containing isolated carbon-carbon double bonds. Concn or 50% aqueous sodium hypochlorite can also be used as an oxidizing agent. /Chemical Carcinogens/
[Montesano, R., H. Bartsch, E.Boyland, G. Della Porta, L. Fishbein, R. A. Griesemer, A.B. Swan, L. Tomatis, and W. Davis (eds.). Handling Chemical Carcinogens in the Laboratory:Problems of Safety. IARC Scientific Publications No. 33. Lyon, France: International Agency for Research on Cancer, 1979. 16]**PEER REVIEWED**

PRECAUTIONS FOR "CARCINOGENS": Carcinogens that are alkylating, arylating or acylating agents per se can be destroyed by reaction with appropriate nucleophiles, such as water, hydroxyl ions, ammonia, thiols & thiosulfate. The reactivity of various alkylating agents varies greatly ... & is also influenced by sol of agent in the reaction medium. To facilitate the complete reaction, it is suggested that the agents be dissolved in ethanol or similar solvents. ... No method should be applied ... until it has been thoroughly tested for its effectiveness & safety on material to be inactivated. For example, in case of destruction of alkylating agents, it is possible to detect residual compounds by reaction with 4(4-nitrobenzyl)-pyridine. /Chemical Carcinogens/
[Montesano, R., H. Bartsch, E.Boyland, G. Della Porta, L. Fishbein, R. A. Griesemer, A.B. Swan, L. Tomatis, and W. Davis (eds.). Handling Chemical Carcinogens in the Laboratory:Problems of Safety. IARC Scientific Publications No. 33. Lyon, France: International Agency for Research on Cancer, 1979. 17]**PEER REVIEWED**

 

Occupational Exposure Standards:

 

 

Threshold Limit Values:

8 hr Time Weighted Avg (TWA) 0.9 mg/cu m, skin
[American Conference of Governmental Industrial Hygienists. Threshold Limit Values (TLVs) for Chemical Substances and Physical Agents Biological Exposure Indices for 1998. Cincinnati, OH: ACGIH, 1998. 31]**PEER REVIEWED**

Excursion Limit Recommendation: Excursions in worker exposure levels may exceed three times the TLV-TWA for no more than a total of 30 min during a work day, and under no circumstances should they exceed five times the TLV-TWA, provided that the TLV-TWA is not exceeded.
[American Conference of Governmental Industrial Hygienists. Threshold Limit Values (TLVs) for Chemical Substances and Physical Agents Biological Exposure Indices for 1998. Cincinnati, OH: ACGIH, 1998. 6]**PEER REVIEWED**

BEI (Biological Exposure Index): Cholinesterase activity in red cells (timing is discretionary) is 70% of individual's baseline. The determinant is usually present in a significant amt in biological specimens collected from subjects who have not been occupationally exposed. Such background levels are incl in the BEI value. The determinant is nonspecific, since it is observed after exposure to some other chemicals. These nonspecific tests are preferred because they are easy to use and usually offer a better correlation with exposure than specific tests. In such instances, a BEI for a specific, less quantitative biological determinant is recommended as a confirmatory test. The biological determinant is an indicator of exposure to the chemical, but the quantitative interpretation of the measurement is ambiguous (semiquantitative). These biological determinants should be used as a screening test if a quantitative test is not practical or as a confirmatory test if the quantitative test is not specific and the origin of the determinant is in question. /Organophosphorus cholinesterase inhibitors/
[American Conference of Governmental Industrial Hygienists. Threshold Limit Values (TLVs) for Chemical Substances and Physical Agents Biological Exposure Indices for 1998. Cincinnati, OH: ACGIH, 1998. 102]**PEER REVIEWED**

A4. A4= Not classifiable as a human carcinogen.
[American Conference of Governmental Industrial Hygienists. Threshold Limit Values (TLVs) for Chemical Substances and Physical Agents Biological Exposure Indices for 1998. Cincinnati, OH: ACGIH, 1998. 31]**PEER REVIEWED**

 

NIOSH Recommendations:

Recommended Exposure Limit: 10 Hr Time-Weighted Avg: 1 mg/cu m, skin.
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 102]**PEER REVIEWED**

 

Immediately Dangerous to Life or Health:

100 mg/cu m
[NIOSH. NIOSH Pocket Guide to Chemical Hazards. DHHS (NIOSH) Publication No. 97-140. Washington, D.C. U.S. Government Printing Office, 1997. 102]**PEER REVIEWED**

 

Other Occupational Permissible Levels:

Australia: 0.1 ppm, skin (1990); Federal Republic of Germany: 0.1 ppm, short-term level 1 ppm, 30 min, once per shift, skin, Pregnancy group C, no reason to fear a risk of damage to the developing embryo or fetus when MAK and BAT values are adhered to (1990); United Kingdom: 0.1 ppm, 10-min STEl 0.3 ppm, skin (1991)
[American Conference of Governmental Industrial Hygienists, Inc. Documentation of the Threshold Limit Values and Biological Exposure Indices. 6th ed. Volumes I,II, III. Cincinnati, OH: ACGIH, 1991. 447]**PEER REVIEWED**

 

Manufacturing/Use Information:

 

 

Major Uses:

CHLORINATED ORGANIC PHOSPHATE INSECTICIDE WITH APPRECIABLE VAPOR PRESSURE. INCORPORATED INTO PLASTIC STRIPS IT SLOWLY RELEASES ... VAPOR. ... HAS BEEN APPROVED FOR USE IN DISINFECTION OF ... AIRCRAFT.
[Gosselin, R.E., R.P. Smith, H.C. Hodge. Clinical Toxicology of Commercial Products. 5th ed. Baltimore: Williams and Wilkins, 1984.,p. II-291]**PEER REVIEWED**

... CONTACT & STOMACH INSECTICIDE WITH FUMIGANT & PENETRANT ACTION. ... USED AS HOUSEHOLD & PUBLIC HEALTH FUMIGANT ...
[Worthing, C.R. and S.B. Walker (eds.). The Pesticide Manual - A World Compendium. 8th ed. Thornton Heath, UK: The British Crop Protection Council, 1987. 269]**PEER REVIEWED**

MEDICATION (VET)
**PEER REVIEWED**

Controls household, public health, stored product insects. Controls mushroom flies, aphids, spider mites, caterpillers, thrips, white flies in glasshouse crops, outdoor fruit, vegetables.
[Farm Chemicals Handbook 1998. Willoughby, OH: Meister Publishing Co., 1998.,p. C-134]**PEER REVIEWED**

 

Manufacturers:

Amvac Chemical Corporation, Hq: 4695 MacArthur Court Suite 1250 Newport Beach, CA 92660 (714)260-1212; Production site: 4100 E. Washington Blvd, Los Angeles, CA 90023 (213)264-3910
[SRI. 1997 Directory of Chemical Producers - United States of America. Menlo Park, CA: SRI International 1997. 832]**PEER REVIEWED**

 

Methods of Manufacturing:

REACTION OF TRIMETHYL PHOSPHITE & CHLORAL
[SRI]**PEER REVIEWED**

Dehydrochlorination of trichlorphon
[Spencer, E. Y. Guide to the Chemicals Used in Crop Protection. 7th ed. Publication 1093. Research Institute, Agriculture Canada, Ottawa, Canada: Information Canada, 1982. 199]**PEER REVIEWED**

Trimethyl phosphite + chloral (Perkow reaction); trichlorfon (dehydrochlorination/rearrangement)
[Ashford, R.D. Ashford's Dictionary of Industrial Chemicals. London, England: Wavelength Publications Ltd., 1994. 291]**PEER REVIEWED**

 

General Manufacturing Information:

Above pH 6, trichlorfon rearranges to form dichlorvos.
[Kirk-Othmer Encyclopedia of Chemical Technology. 4th ed. Volumes 1: New York, NY. John Wiley and Sons, 1991-Present.,p. V14 556]**PEER REVIEWED**

A slow release insecticide preparation for use in rooms, warehouses, etc, is manufactured using inert aluminum silicate enhancer. Thus, an aluminum silicate plate (60 g) is soaked in a solution containing 20 g dichlorvos and 0.5 g xanthine derivative. The preparation lasted 3-4 months, and the effective space for its activity was 20-30 cu m.
[Hui MX et al; Evaporable Insecticide Preparations. Peoples Republic of China Patent No. 8510037 (03/10/86) assigned to Hunan University]**PEER REVIEWED**

Sustained release PVC incorporated insecticidal formulations are given, which also contain insect stimulating materials (dyes, flavors, etc). Thus, a formulation contains PVC 100, di-(2-ethylhexyl)phthalate 47, metal soap 2, stearic acid 0.2, dichlorvos 10-30, gelatin 2, and aluminum hydroxide 10 parts.
[Nemeth L et al; Sustained-Release Insecticide Formulation. Hungarian Teljes Patent No. 38202 (05/28/86) assigned to Rozsa, Laszlo]**PEER REVIEWED**

Finely dispersed carriers are impregnated with a compound containing a urethane prepolymer isocyanates, polyols and pesticides. The compound is polymerized, molded, and made into a pest control collar for pets. The pesticide containing particles in the urethane polymer gradually flake off from the collar by friction and control pests for a prolonged period. The compound contains an organic isocyanate-polyester polyol (molecular weight 3000) 15, isocyanate-polyether polyol (molecular weight 1000) 8, Ti-coupled aluminum hydroxide particles (80 u m/40 u m= 1/4) 75.5, and insecticide (eg, dichlorvos, allethrin) 1.5%.
[Shikinami Y et al; Pesticidal Collar for Pets. Japan Kokai Tokkyo Koho Patent No. 86 91102 (05/09/86) assigned to Takiron Co, Ltd]**PEER REVIEWED**

... non-phytotoxic (except to some Chrysanthemum cultivars) ... & Non-persistent.
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium, 11 th ed., British Crop Protection Council, Surrey, England 1997 373]**PEER REVIEWED**

 

Formulations/Preparations:

Aerosols; soluble concentrates; multi-layered laminated strip
[Farm Chemicals Handbook 1998. Willoughby, OH: Meister Publishing Co., 1998.,p. C-134]**PEER REVIEWED**

 

Impurities:

Dichlorvos is available in the USA as a technical grade containing not less than 93 wt% of the pure chemical and not more than 7 wt% of insecticidally active related cmpd. Technical grade dichlorvos can contain trichlorphon.
[IARC. Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Man. Geneva: World Health Organization, International Agency for Research on Cancer,1972-PRESENT. (Multivolume work).,p. V20 98 (1973)]**PEER REVIEWED**

 

Consumption Patterns:

ESSENTIALLY 100% AS A PESTICIDE
[SRI]**PEER REVIEWED**

 

Laboratory Methods:

 

 

Clinical Laboratory Methods:

ESTIMATION OF CHOLINESTERASE ACTIVITY OF ORGANOPHOSPHORUS INSECTICIDES IN HUMAN RED BLOOD CELLS AND PLASMA BY INCUBATION WITH KNOWN EXCESS OF CHOLINESTERASE & ADDN OF KNOWN EXCESS OF ACETYLCHOLINE. ACETIC ACID PRODUCED DETERMINED FROM CHANGE IN PH (PH METER). /ORGANOPHOSPHORUS INSECTICIDES/
[Bergmeyer, H.W. (ed.). Methods of Enzymatic Analysis. 2nd English ed. New York City: Academic Press, 1974. 2249]**PEER REVIEWED**

 

Analytic Laboratory Methods:

PRODUCT ANALYSIS: ... BY IR SPECTROSCOPY ... RESIDUES MAY BE DETERMINED BY GLC ...
[Worthing, C.R. and S.B. Walker (eds.). The Pesticide Manual - A World Compendium. 8th ed. Thornton Heath, UK: The British Crop Protection Council, 1987. 270]**PEER REVIEWED**

NIOSH Method 295. Analyte: Dichlorvos. Matrix: Air. Procedure: Gas chromatography/flame photometric detector. Method was validated over the range of 0.382 to 1.707 mg/cu m using a 120 liter sample. Method detection limit 0.2 ug/sample. Precision (CVt): 0.054. Interference: A compound with the same retention time as the analyte is an interference.
[U.S. Department of Health, Education Welfare, Public Health Service. Center for Disease Control, National Institute for Occupational Safety Health. NIOSH Manual ofAnalytical Methods. 2nd ed. Volumes 1-7. Washington, DC: U.S. Government Printing Office, 1977-present.,p. 295-1]**PEER REVIEWED**

Product analysis is by reaction with excess of iodine which is estimated by titration or by glc.
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium, 11 th ed., British Crop Protection Council, Surrey, England 1997 373]**PEER REVIEWED**

A colorimetric method for the determination of the organic phosphate metabolites of dichlorvos in urine requires extraction with ether and uses ascorbic acid as the chromogenic reagent. The resultant colored solution is analyzed with a visible spectrophotometer at a wavelength of 820 nm. Calculation is based on a response factor derived from a standard curve. This method has a sensitivity of 0.2 mg/l.
[Baselt RC; Biological Monitoring Methods for Industrial Chemicals p.106-7 (1980)]**PEER REVIEWED**

Determination of organophosphorus pesticide residues in food with two-dimensional gas chromatography using capillary columns and flame photometric detection is described. /Organophosphorus pesticide/
[Stan HJ, Mrowetz D; J High Resolut Chromatogr Commun 6 (5): 255-63 (1983)]**PEER REVIEWED**

ASTM Method D3695: Volatile Alcohols in Water by GC: Standard Test Method for Volatile Alcohols in Water by Direct Aqueous-Injection Gas Chromatography; GC with flame ionization detection, wastewater, detection limit of 1.0 mg/l.
[USEPA; EMMI. EPA's Environmental Monitoring Methods Index. Version 1.1. PC# 4082. Rockville, MD: Government Institutes (1997)]**PEER REVIEWED**

 

Sampling Procedures:

Trap in acetone using spectrophotometry of resorcinol complex at 490 nm; detection limit of 0.14 mg/cu m. /From table/
[IARC. Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Man. Geneva: World Health Organization, International Agency for Research on Cancer,1972-PRESENT. (Multivolume work).,p. V20 102 (1979)]**PEER REVIEWED**

NIOSH Method 295. Analyte: Dichlorvos. Matrix: Air. Procedure: Adsorption on XAD-2 and desorption with toluene. Flow Rate: 0.5 and 1 l/min. Sample Size: 120-liters.
[U.S. Department of Health, Education Welfare, Public Health Service. Center for Disease Control, National Institute for Occupational Safety Health. NIOSH Manual ofAnalytical Methods. 2nd ed. Volumes 1-7. Washington, DC: U.S. Government Printing Office, 1977-present.,p. 295-1]**PEER REVIEWED**

Special References:

Special Reports:

Dichlorvos is found in an EPA document entitled Chemical Emergency Preparedness Program: Interim Guidance (Nov, 1985). This voluntary program provides two goals: to increase community awareness of chemical hazards and to develop state and local emergency response plans for dealing with chemical accidents.
[Roytech/SOCMA Suspect Chemicals Source Book. 4th ed. Burlingame, CA: Roytech Publications, 1985.,p. IV-230]

Santodonato J; Monograph on Human Exposure to Chemicals in the Workplace: Dichlorvos 31 pp. NTIS PPB86-148343 (1985)

Sternberg SS; Int Encycl Pharmacol Ther 113: 561-80 (1984). The carcinogenesis, mutagenesis of insecticides is presented. Reviews both animal and human data.

World Health Organization; Monograph on Dichlorvos (1989). Topics covered in this literature review are: physical and chemical properties and analytical methods; sources of human and environmental exposure; kinetics and metablism; effects on organisms; effects on experimental animals; effects on man; evaluation of human health risks and effects on the environment.

Synonyms and Identifiers:

Related HSDB Records:

881 [TRICHLORFON] (METABOLIC PRECURSOR)

Synonyms:

Apavap
**PEER REVIEWED**

Astrobot
**PEER REVIEWED**

Atgard
**PEER REVIEWED**

Atgard C
**PEER REVIEWED**

BAY-19149
**PEER REVIEWED**

Benfos
**PEER REVIEWED**

BIBESOL
**PEER REVIEWED**

Brevinyl
**PEER REVIEWED**

BREVINYL E50
**PEER REVIEWED**

CANOGARD
**PEER REVIEWED**

Cekusan
**PEER REVIEWED**

CHLORVINPHOS
**PEER REVIEWED**

Cypona
**PEER REVIEWED**

DDVP
**PEER REVIEWED**

Dedevap
**PEER REVIEWED**

DERIBAN
**PEER REVIEWED**

DERRIBANTE
**PEER REVIEWED**

Des
**PEER REVIEWED**

Devikol
**PEER REVIEWED**

(2,2-DICHLOOR-VINYL)-DIMETHYL-FOSFAAT (DUTCH)
**PEER REVIEWED**

(2,2-Dichloor-vinyl)-dimethyl-phosphat (German)
**PEER REVIEWED**

DICHLOORVO (DUTCH)
**PEER REVIEWED**

Dichlorfos (Polish)
**PEER REVIEWED**

Dichlorman
**PEER REVIEWED**

2,2-Dichloroethenyl dimethyl phosphate
**PEER REVIEWED**

2,2-DICHLOROETHENYL PHOSPHORIC ACID DIMETHYL ESTER
**PEER REVIEWED**

DICHLOROVAS
**PEER REVIEWED**

(2,2-DICHLORO-VINIL)DIMETIL-FOSFATO (ITALIAN)
**PEER REVIEWED**

2,2-DICHLOROVINYL DIMETHYL PHOSPHATE
**PEER REVIEWED**

Dichlorovos
**PEER REVIEWED**

DICHLORPHOS
**PEER REVIEWED**

O-(2,2-DICHLORVINYL)-O,O-DIMETHYLPHOSPHAT (GERMAN)
**PEER REVIEWED**

DIMETHYL 2,2-DICHLOROETHENYL PHOSPHATE
**PEER REVIEWED**

O,O-DIMETHYL DICHLOROVINYL PHOSPHATE
**PEER REVIEWED**

O,O-DIMETHYL O-2,2-DICHLOROVINYL PHOSPHATE
**PEER REVIEWED**

DIMETHYL 2,2-DICHLOROVINYL PHOSPHATE
**PEER REVIEWED**

Divipan
**PEER REVIEWED**

Duo-kill
**PEER REVIEWED**

Duravos
**PEER REVIEWED**

ENT 20738
**PEER REVIEWED**

EQUIGEL
**PEER REVIEWED**

ESTROSEL
**PEER REVIEWED**

Estrosol
**PEER REVIEWED**

ETHENOL, 2,2-DICHLORO-, DIMETHYL PHOSPHATE
**PEER REVIEWED**

FECAMA
**PEER REVIEWED**

HERKAL
**PEER REVIEWED**

HERKOL
**PEER REVIEWED**

KRECALVIN
**PEER REVIEWED**

MAFU
**PEER REVIEWED**

Mafu strip
**PEER REVIEWED**

MARVEX
**PEER REVIEWED**

NCI-C00113
**PEER REVIEWED**

Nefrafos
**PEER REVIEWED**

NERKOL
**PEER REVIEWED**

NOGOS
**PEER REVIEWED**

No-pest
**PEER REVIEWED**

NO-PEST STRIP
**PEER REVIEWED**

NUVA
**PEER REVIEWED**

NUVAN
**PEER REVIEWED**

OMS 14
**PEER REVIEWED**

PHOSPHATE DE DIMETHYLE ET DE 2,2-DICHLOROVINYLE (FRENCH)
**PEER REVIEWED**

PHOSPHORIC ACID, 2,2-DICHLOROETHENYL DIMETHYL ESTER
**PEER REVIEWED**

PHOSPHORIC ACID, 2,2-DICHLOROVINYL DIMETHYL ESTER
**PEER REVIEWED**

PHOSVIT
**PEER REVIEWED**

SD 1750
**PEER REVIEWED**

SZKLARNIAK
**PEER REVIEWED**

TASK
**PEER REVIEWED**

Tetravos
**PEER REVIEWED**

Unifos
**PEER REVIEWED**

VAPONA
**PEER REVIEWED**

VAPONITE
**PEER REVIEWED**

Vinylofos
**PEER REVIEWED**

Winylophos
**PEER REVIEWED**

Formulations/Preparations:

Aerosols; soluble concentrates; multi-layered laminated strip
[Farm Chemicals Handbook 1998. Willoughby, OH: Meister Publishing Co., 1998.,p. C-134]**PEER REVIEWED**

Shipping Name/ Number DOT/UN/NA/IMO:

NA 2783; Dichlorvos
UN 2783; Organophosphorus pesticides, solid, toxic, NOS
UN 3018; Organophosphorus pesticides, liquid, toxic, NOS
UN 2784; Organophosphorus pesticides, liquid, toxic, flammable, NOS, flashpoint 23 deg C or more
UN 3017; Organophosphorus pesticides, liquid, toxic, flammable, NOS, flashpoint less than 23 deg C
IMO 6.1; Organophosphorus pesticides, solid, toxic, NOS; Organophosphorus pesticides, liquid, toxic, flammable, NOS, flashpoint 23 deg C or more; Organophosphorus pesticides, liquid, toxic, flammable, NOS, flashpoint less than 23 deg C; Organophosphorus pesticides, liquid, toxic, NOS

Standard Transportation Number:

49 215 34; Dichlorvos (agricultural insecticides, not elsewhere classified, liquid)
49 215 35; Dichlorvos (agricultural insecticides, not elsewhere classified, other than liquid)
49 215 36; Dichlorvos (insecticides, other than agricultural, not elsewhere classified)
49 215 37; Dichlorvos mixture, dry (agricultural insecticides, other than liquid)

RTECS Number:

NIOSH/TC0350000

Administrative Information:

Hazardous Substances Databank Number: 319
Last Revision Date: 20010809
Last Review Date: Reviewed by SRP on 1/31/1999
Update History:

Complete Update on 08/09/2001, 1 field added/edited/deleted.
Complete Update on 05/15/2001, 1 field added/edited/deleted.
Complete Update on 05/25/2000, 3 fields added/edited/deleted.
Field Update on 02/08/2000, 1 field added/edited/deleted.
Field Update on 02/02/2000, 1 field added/edited/deleted.
Field Update on 11/18/1999, 1 field added/edited/deleted.
Field Update on 09/21/1999, 1 field added/edited/deleted.
Field Update on 08/26/1999, 1 field added/edited/deleted.
Complete Update on 08/06/1999, 66 fields added/edited/deleted.
Field Update on 03/17/1999, 1 field added/edited/deleted.
Field Update on 11/17/1998, 1 field added/edited/deleted.
Complete Update on 06/02/1998, 1 field added/edited/deleted.
Complete Update on 02/25/1998, 1 field added/edited/deleted.
Complete Update on 10/17/1997, 1 field added/edited/deleted.
Complete Update on 05/08/1997, 1 field added/edited/deleted.
Complete Update on 04/01/1997, 3 fields added/edited/deleted.
Complete Update on 03/17/1997, 2 fields added/edited/deleted.
Complete Update on 03/07/1997, 4 fields added/edited/deleted.
Field Update on 03/06/1997, 1 field added/edited/deleted.
Complete Update on 10/12/1996, 1 field added/edited/deleted.
Complete Update on 09/10/1996, 1 field added/edited/deleted.
Complete Update on 07/11/1996, 1 field added/edited/deleted.
Complete Update on 06/06/1996, 1 field added/edited/deleted.
Complete Update on 05/09/1996, 1 field added/edited/deleted.
Complete Update on 04/16/1996, 7 fields added/edited/deleted.
Complete Update on 01/18/1996, 1 field added/edited/deleted.
Complete Update on 01/18/1995, 1 field added/edited/deleted.
Complete Update on 12/19/1994, 1 field added/edited/deleted.
Complete Update on 10/11/1994, 1 field added/edited/deleted.
Complete Update on 09/26/1994, 1 field added/edited/deleted.
Complete Update on 09/08/1994, 8 fields added/edited/deleted.
Field Update on 07/22/1994, 1 field added/edited/deleted.
Field Update on 05/05/1994, 1 field added/edited/deleted.
Field Update on 03/21/1994, 1 field added/edited/deleted.
Field Update on 01/25/1994, 1 field added/edited/deleted.
Field Update on 09/02/1993, 1 field added/edited/deleted.
Complete Update on 08/07/1993, 1 field added/edited/deleted.
Complete Update on 08/04/1993, 1 field added/edited/deleted.
Field update on 12/12/1992, 1 field added/edited/deleted.
Complete Update on 09/14/1992, 69 fields added/edited/deleted.
Complete Update on 08/17/1992, 69 fields added/edited/deleted.
Field Update on 04/16/1992, 1 field added/edited/deleted.
Field Update on 01/13/1992, 1 field added/edited/deleted.
Field Update on 09/13/1991, 1 field added/edited/deleted.
Field Update on 09/12/1991, 1 field added/edited/deleted.
Field Update on 09/11/1991, 1 field added/edited/deleted.
Field Update on 09/10/1991, 1 field added/edited/deleted.
Complete Update on 05/08/1991, 1 field added/edited/deleted.
Complete Update on 10/22/1990, 15 fields added/edited/deleted.
Field Update on 05/14/1990, 1 field added/edited/deleted.
Field Update on 03/06/1990, 1 field added/edited/deleted.
Field Update on 01/15/1990, 1 field added/edited/deleted.
Complete Update on 01/11/1990, 12 fields added/edited/deleted.
Field Update on 05/05/1989, 1 field added/edited/deleted.
Field Update on 03/01/1989, 1 field added/edited/deleted.
Field Update on 05/12/1988, 1 fields added/edited/deleted.
Complete Update on 03/04/1988, 91 fields added/edited/deleted.
Complete Update on 05/02/1985

Record Length: 239020