Agent Name

EPN

Alternative Name

O-Ethyl-O-(4-nitrophenyl)phenylthiophosphonate

CAS Number

2104-64-5

Formula

C14-H14-N-O4-P-S

Major Category

Pesticides

Synonyms

O-Ethyl-O-(4-nitrophenyl)phenylthiophosphonate; O-Ethyl O-(4-nitrophenyl) benzenephosphonothioate; Ethyl p-nitrophenyl benzenethionophosphonate; O-Ethyl-O-(4-nitrophenyl)phenylthiophosphonate;

Category

Organophosphate Insecticides

Description

Yellow solid with an aromatic odor. [pesticide] [Note: A brown liquid above 97 degrees F.] [NIOSH]

Comments

A small number of the organophosphates (OPs) can Induce Delayed Neuropathy (OPIDN). OPIDN usually occurs after ingestion and is usually nonoccupational. [Levy, p. 431] The average of two baseline respective cholinesterase activity determinations three days apart, with no exposures to enzyme inhibiting pesticides for at least 30 days, is recommended for each worker prior to exposure to cholinesterase inhibitors because of large inter-individual differences in published baseline values. To be established at least once a year. Removal from workplace exposures is recommended until the cholinesterase activity returns to within 20% of baseline. [TLVs and BEIs]

Restricted

"No ACTIVE registrants found for selected chemical." [NPIRS] Use as mosquito larvacide cancelled in 1983; All registrations voluntarily cancelled in 1987; [EPA: Status of Chemicals in Special Review]

Reference Link

NIOSH Occupational Health Guidelines for Chemical Hazards: EPN

Exposure Assessment
BEI

Acetylcholinesterase activity in red blood cells = 70% of individual's baseline; Butylcholinesterase activity in serum or plasma = 60% of individual's baseline; Sample at end of shift; [TLVs and BEIs]

Skin Designation (ACGIH)

Yes

TLV (ACGIH)

0.1 mg/m3, inhalable fraction

PEL (OSHA)

0.5 mg/m3

MAK

0.5 mg/m3, inhalable fraction

IDLH (NIOSH)

5 mg/m3

Vapor Pressure

9.5E-7 mm Hg

Explanatory Notes

See "2018 Notice of Intended Changes." [TLVs and BEIs]

Adverse Effects
Neurotoxin

Motor Neuropathy

Other Poison

Organophosphate

ACGIH Carcinogen

Not Classifiable

Links to Other NLM Databases
Health Studies

Human Health Effects from Hazardous Substances Data Bank:

Toxicity Information

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Chemical Information

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Related Information in HazMap
Diseases

Occupational diseases associated with exposure to this agent: