NIOSH REL: 0.05 mg/m3 TWA [skin]
Current OSHA PEL: 0.1 mg/m3 TWA [skin]
1989 OSHA PEL: Same as current PEL
1993-1994 ACGIH TLV: 0.1 mg/m3 TWA [skin]
Description of substance: Paleyellow to darkbrown liquid with a garliclike odor.
LEL: . . Unknown
Original (SCP) IDLH: 20 mg/m3
Basis for original (SCP) IDLH: No useful data on acute inhalation toxicity are available on which to base the IDLH for parathion. If the IDLH were estimated from the statement by AIHA [1971] that "the minimum lethal oral dose for humans has been estimated as ranging from less than 10 mg to 120 mg [Bidstrup 1950; Grob 1950; Hayes 1963]," then an IDLH of 5 mg/m3 would be chosen. This appears to be far too conservative, however, because ACGIH [1971] noted that workers regularly exposed to 2 to 15 mg/m3, with an average concentration of 8 mg/m3, exhibited only a 25% decrease in cholinesterase levels [Kay et al. 1952]. The chosen IDLH, therefore, has been estimated from the female rat oral LD50 of 3 mg/kg cited by ACGIH [1971].
Short-term exposure guidelines: None developed
ACUTE TOXICITY DATA:
Lethal concentration data:
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Rabbit
G. pig Mouse Rat |
Deichmann et al. 1952
Deichmann et al. 1952 Izmerov et al. 1982 USAF 1977 |
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Lethal dose data:
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Mouse
Rabbit Dog Cat Horse G. pig Rat | Eto et al. 1966
Kenaga & Morgan 1978 Kenaga & Morgan 1978 Nishizawa et al. 1961 Perkow 1971/1976 von Dozent et al. 1955 Weiss and Orzel 1967 |
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Human data: Workers regularly exposed to 2 to 15 mg/m3
(average of 8 mg/m3) exhibited only a 25% decrease
in cholinesterase levels [CDC 1956]. The minimum lethal oral dose
has been reported to range from 0.17 to 1.471 mg/kg [Arena
1970; CDC 1956; Hartley and Kidd 1986]. [Note: An oral dose ranging
from 0.17 to 1.471 mg/kg is equivalent to a worker being
exposed to about 8 to 69 mg/m3 for 30 minutes,
assuming a breathing rate of 50 liters per minute and 100%
absorption.]
Revised IDLH: 10 mg/m3
Basis for revised IDLH: The revised IDLH for parathion is 10 mg/m3 based on chronic inhalation toxicity data in humans [CDC 1956]. This may be a conservative value due to the lack of relevant acute toxicity data in humans exposed to concentrations above 10 mg/m3. |
REFERENCES:
1. ACGIH [1971]. Parathion. In: Documentation of the threshold limit values for substances in workroom air. 3rd ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, pp. 195196.
2. AIHA [1969]. Parathion. In: Hygienic Guide Series. Am Ind Hyg Assoc J 30:308312.
3. Arena JM [1970]. Poisoning, toxicology, symptoms, treatments. 2nd ed. Springfield, IL: C.C. Thomas 2:73.
4. Bidstrup PL [1950]. Poisoning by organic phosphorus insecticides. Br Med J 2:548551.
5. CDC [1956]. Clinical memoranda on economic poisons. Atlanta, GA: Communicable Disease Center, Bureau of State Services, Public Health Service, U.S. Department of Health, Education, and Welfare, Public Health Service Publication No. 476, pp. 1921.
6. Deichmann WB, Pugliese W, Cassidy J [1952]. Effects of dimethyl and diethyl paranitrophenyl thiophosphate on experimental animals. AMA Arch Ind Health Occup Med 5:4451.
7. Eto M, Kishimoto K, Matsumura K, Ohshita N, Oshima Y [1966]. Studies on saligenin cyclic phosphorus esters with insecticidal activity. Agri Biol Chem 30(2):181185.
8. Grob D [1950]. Uses and hazards of the organic phosphate anticholinesterase compounds. Ann Intern Med 32:12291234.
9. Hartley D, Kidd H, eds. [1986]. Agrochemicals handbook. Nottingham, England: Royal Society of Chemistry. 19831986, p. A311.
10. Hayes WJ Jr [1963]. Clinical handbook on economic poisons. Emergency information for treating poisons. Washington, DC: U.S. Government Printing Office, Public Health Service Publication No. 476 (Revised 1963), pp. 3537.
11. Izmerov NF, Sanotsky IV, Sidorov KK [1982]. Toxicometric parameters of industrial toxic chemicals under single exposure. Moscow, Russia: Centre of International Projects, GKNT, p. 52.
12. Kay K, Monkman L, Windish JP, Doherty T, Pare J, Racicot C [1952]. Parathion exposure and cholinesterase response of Quebec apple growers. AMA Arch Ind Hyg Occup Med 6:252262.
13. Kenaga EE, Morgan RW [1978]. Commercial and experimental organic insecticides (1978 revision). Entomological Society of America Special Publication 781:16.
14. Nishizawa Y, Fujii K, Kadota T, Miyamoto J, Sakamoto H [1961]. Studies on the organophosphorus insecticides. VII. Chemical and biological properties of new low toxic organophosphorus insecticide. O,OdimethylO(3methyl4nitrophenyl) phosphorothioate. Agri Biol Chem 25(8):605610.
15. Perkow W [1971/1976]. Wirksubstanzen der pflanzenschutz und schadlingsbekampfungsmittel. Berlin, Germany: Verlag Paul Parey, 19711976 (in German).
16. USAF [1977]. Proceedings of the 7th annual conference on environmental toxicology. WrightPatterson Air Force Base, OH: Air Force Systems Command, Aerospace Medical Division, Aerospace Medical Research Technical Report, AMRLTR76125.
17. von Dozent J, Klimmer OR, Pfaff W [1955]. Vergleichende untersuchungen über die toxicität organischer thiophosphorsäureester. Arzneimittel-Forschung (Drug Research) 5:626630 (in German).
18. Weiss LR, Orzel RA [1967]. Some comparative toxicologic and
pharmacologic effects of dimethyl sulfoxide as a pesticide solvent.
Toxicol Appl Pharmacol 11:546557.
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