PARATHION | Occupational Safety and Health Administration

PARATHION†

Chemical Identification
CAS #	56-38-2
Formula	C₁₀H₁₄NO₅PS
Synonyms	O,O-diethyl-O(p-nitrophenyl) phosphorothioate; diethyl parathion; ethyl parathion; parathion-ethyl

Physical Properties
Physical description	Pale-yellow to dark-brown liquid with a garlic-like odor.
Boiling point	707°F	Molecular weight	291.3
Freezing point/melting point	43°F	Vapor pressure	0.00004 mmHg
Flash point	248-320F	Vapor density
Specific gravity	1.27	Ionization potential
Lower explosive limit (LEL)		Upper explosive limit (UEL)
NFPA health rating	4	NFPA fire rating	1
NFPA reactivity rating	2	NFPA special instruction
Vapor hazard ratio (VHR)
Historical exceedance percentage
Target organs

Monitoring Methods Used by OSHA
Analyte code (IMIS no.)	1984
Sampling group
Sampler/Sampling media	OSHA versatile sampler (OVS-2) - 13 mm XAD-2 tube (270/140 mg) with GFF enclosed [SKC 226-30-16]
Sampling time^*	480 min
Sampling volume (TWA)^*	480 L
Sampling flow rate (TWA)^*	1 L/min
Sampling volume (STEL/Peak/C)^*	15 L
Sampling flow rate (STEL/Peak/C)^*	1 L/min
Analytical method instruments	GC-FPD
Method reference	OSHA 62 (fully validated)
Notes
Special requirements

^* All sampling instructions above are recommended guidelines for OSHA Compliance Safety and Health Officers (CSHOs), please see the corresponding OSHA method reference for complete details.

Bulk/Wipe Method
Wipe Sampler/Sampling media	Wipe with GFF (37 mm), Type A/E [AP4003705]
Bulk Method	Limit the amount of bulk submitted to 1 g or 1 mL.

On-Site Screening Techniques
Device
Model/Type
Sampling information (see manufacturer instructions)

**Exposure Limits**
OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak		NIOSH REL Up to 10-hour TWA (ST) STEL (C) Ceiling		ACGIH TLV© 8-hour TWA (ST) STEL (C) Ceiling		CAL/OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak
PEL-TWA	0.1 mg/m³	REL-TWA	0.05 mg/m³	TLV-TWA	0.05 mg/m³ (inhalable fraction and vapor) [2000]	PEL-TWA	0.1 mg/m³
PEL-STEL		REL-STEL		TLV-STEL		PEL-STEL
PEL-C		REL-C		TLV-C		PEL-C
Skin notation	Y	Skin notation	Y	Skin notation	Y	Skin notation	Y
Notes: See 29 CFR 1910.1000 Table Z-1.		Notes:		Notes: BEI®		Notes:
Health factors: See NIH-NLM PubChem.		IDLH	10 mg/m³
Carcinogenic classifications: IARC-3, TLV-A4, EPA-C		Notes:
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:

Additional Resources and Literature References

NOAA: CAMEO Chemicals - Parathion

NIOSH: Pocket Guide to Chemical Hazards - Parathion

Literature References

ACGIH: Documentation of the Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs) - 2017.
EPA Air Toxics Website: Parathion. U.S. Environmental Protection Agency Technology Transfer Network.
Lee, B.W., London, L., Paulauskis, J., Myers, J. and Christiani, D.C.: Association between human paraoxonase gene polymorphinsm and chronic symptoms in pesticide-exposed workers. J. Occup. Environ. Med. 45(2): 118-122, 2003.
Mutch, E., Daly, A.K., Leathart, J.B.S., Blain, P.G. and Williams, F.M.: Do multiple cytochrome P450 isoforms contribute to parathion metabolism in man? Arch. Toxicol. 77(6): 313-320, 2003.
Pohanish, R.P. (editor): Parathion. In, Sittig's Handbook of Toxic and Hazardous Chemicals and Carcinogens, Fourth Ed., Vol. 2. Norwich, NY: Noyes Publications, William Andrew Publishing, 2002, pp. 1788-1791.

Last Updated Date : 01/07/2021

PARATHION†

Chemical Identification

Physical Properties

Monitoring Methods Used by OSHA

Bulk/Wipe Method

On-Site Screening Techniques

Exposure Limits

Additional Resources and Literature References