(0.01 . TM The ToxGuide is developed to be used as a pocket guide.

Sources of Exposure Toxicokinetics and Biomarkers/Environmental Normal Human Levels Levels TM ToxGuide General Populations Toxicokinetics Biomarkers . Contaminated air was a potential so u rce . Parathion can be readily absorbed from . Parathion can be measured in blood or for of exposure to parathion among the the skin; available data indicate that urine. Some parathion metabolites in general population living near areas parathion can be absorbed from the urine may serve as biomarkers as well. where the insecticide was used; however lungs and gastrointestinal tract as well. Parathion it is no longer used in the United States. . Available animal data indicate a high Environmental Levels . Contaminated food was another likely affinity of parathion for adipose tissue Air C10H14NO5PS source of general population exposure to and the liver; lower levels of parathion parathion; a lesser source of exposure and its active metabolite (paraoxon) were . Ambient air levels of 0.017–0.089 μg/m3 may have been contaminated drinking detected in muscles, lung, and brain. were measured when parathion was used CAS# 56-38-2 in the past in the United States. water. . The liver is the main site for parathion Soil January 2017 . However, given that EPA cancelled all metabolism; however, metabolism has registered uses in 2006, the potential for been observed in kidney, lung, and brain . Parathion was not detected in most soil human exposure to parathion through as well. Some parathion metabolites samples, but was sometimes detectable in the diet or drinking water in the United (mainly paraoxon) are to xic. close proximity to application sites (e.g., U.S. Department of Health and States is low. . Most parathion is eliminated through in drainage ditches). Water Human Services metabolism and subsequent excretion in Public Health Service Occupational Populations urine; a small proportion of metabolites . Parathion in surface waters generally may be excreted in feces. Agency for Toxic Substances . Contaminated air and dermal contact ranged from not detectable to 160 ppt. and Disease Registry Parathion was not detected in most were sources of exposure for workers www.atsdr.cdc.gov drinking water samples; but was detected previously involved in the manufacture Normal Human Levels at 4.6 ppb in one drinking water well. and/or agricultural application of the Contact Information: . Parathion is not likely to be found in Food insecticide. However, given that its Division of Toxicology blood, tissues, urine, or feces because it is . registered uses have been cancelled, there no longer manufactured or used as an Average levels in food items between the and Human Health Sciences is no longer a potential for occupational insecticide in the United States. years 1994 and 2000 ranged from not Environmental Toxicology Branch exposure to parathion in the United detectable to 1.6 ppm.

States. 1600 Clifton Road NE, F-57 Atlanta, GA 30329-4027 1-800-CDC-INFO Reference 1-800-232-4636 Agency for Toxic Substances and Disease Registry (ATSDR). 2017. Toxicological Profile for Parathion. Atlanta, GA: U.S. Department of Health and Human Services, Public Health Service.

Chemical and Physical Information Routes of Exposure Relevance to Public Health (Health Effects)

Parathion is a Liquid (pure) or . Inhalation and Dermal–Formerly Health effects are determined Health Effects Solid (formulated) significant routes of exposure for the . The nervous system is the main target of general population and farm workers in by the dose (how much), the parathion toxicity and is typical of other . Parathion is an organophosphorus areas where parathion was used, and duration (how long), and the insecticide with a garlic- or phenol-like organophosphates. among workers involved in production, route of exposure. odor that is pale yellow (pure), dark formulation, and handling of parathion. . Typical signs and symptoms of brown (technical grade liquid generally in organophosphate intoxication include . Oral – Former possible route of exposure an organic solvent), or colorless to white Minimal Risk Levels (MRLs) reduced plasma and red blood cell through ingestion of parathion-treated (formulated solid). Inhalation acetylcholinesterase activity, excessive food sources; small children may have bronchial secretions, respiratory distress, . Parathion has been banned for all uses in come into contact with parathion . No acu te-duration (≤14 days) inhalation salivation, pinpoint pupils, bradycardia, the United States. residues in soil and dust via hand-to- MRL was derived for parathion. abdominal cramps, diarrhea, tremor, mouth activity. . An intermediate-duration (15-364 days) fasciculations, and possibly death inhalation MRL of 20 ng/m3 was derived . EPA concluded that parathion is a for parathion. . “possible human carcinogen” based on Parathion in the Environment No ch ronic-duration (≥365 days) limited animal data. The International inhalation MRL was derived for . Parathion in air via agricultural spraying Agency for Research on Cancer (IARC) parathion. has concluded that parathion is possibly would be expected to exist in vapor and particulate phases; in air parathion would carcinogenic to humans. Oral be expected to be degraded in the presence of sunlight and ozone. . No acu te-duration (≤14 days) oral MRL Children’s Health was derived for parathion. . Parathion in surface water or soils would . 1 Children exposed to parathion would tend to adsorb to soils and sediments; . An intermediate-duration (15-364 days) be expected to experience effects this would limit its mobility, volatilization oral MRL of 0.009 mg/kg/day was derived characteristic of organophosphate from water surfaces, susceptibility to for parathion. poisoning. photolysis, bioavailability, and . No chronic-duration (≥365 d ays) oral MRL . No studies were located regarding biodegradation. was derived for parathion. parathion in human breast milk, but there . Parathion in surface water may be subject is indirect evidence for transfer of to both abiotic degradation via hydrolysis parathion via the placenta and/or breast and photolysis and biotic degradation by milk in animals. microorganisms. . The potential for parathion-induced . Parathion in soils and sediments can be developmental effects in humans has not degraded by hydrolysis, photolysis, and been adequately evaluated. Oral microorganisms. exposure of pregnant rats and rabbits to . Parathion does not significantly parathion did not result in developmental bioaccumulate in aquatic organisms. effects.