Agent Name


CAS Number




Major Category



(O,O-Dimethyl-phthalimidiomethyl-dithiophosphate); APPA; Decemthion; Decemthion P-6; Decemtion P-6; ENT 25,705; Fosmet; Ftalophos; Imidan; Imidan 5 Dust; Imidan WP; Imidathion; Kemolate; N-(Dimethoxyphosphinothioylthiomethyl)phthalimide; N-(Mercaptomethyl)phthalimide S-(O,O-dimethyl phosphorodithioate); O,O-Dimethyl S-(N-phthalimidomethyl)dithiophosphate; O,O-Dimethyl S-(phthalimididomethyl)phosphorodithioate; O,O-Dimethyl S-(phthalimidomethyl) dithiophosphate; O,O-Dimethyl S-(phthalimidomethyl)phosphorodithioate; O,O-Dimethyl S-phthalimidomethyl phosphorodithioate; O,O-Dimethyl phosphorodithioate S-ester with N-(mercaptomethyl)phthalimide; PMP; PMP (pesticide); Percolate; Phosphorodithioic acid O,O-dimethyl ester S-ester with N-(mercaptomethyl) phthalimide; Phosphorodithioic acid, O,O-dimethyl ester, S-ester with N-(mercaptomethyl)phthalimide; Phosphorodithioic acid, S-((1,3-dihydro-1,3-dioxo-isoindol-2-yl)methyl) O,O-dimethyl ester; Phtalofos; Phthalimide, N-(mercaptomethyl)-, S-ester with O,O-dimethyl phosphorodithioate; Phthalimidomethyl O,O-dimethyl phosphorodithioate; Phthalophos; Prolate; Prolate 5 Dust; Prolate 8-OS; Prolate E; R 1504; R-1504; S-((1,3-Dihydro-1,3-dioxo-2H-isoindol-2-yl)methyl) O,O-dimethyl phosphorodithioate; S-((1,3-Dioxo-2H-isoindol-2-yl)methyl) O,O-dimethyl phosphorodithioate; Safidon; Simidan; Smidan; Stauffer R 1504; [ChemIDplus] UN2783


Organophosphate Insecticides


Colorless to off-white solid; [ICSC] Technical product is off-white or pink solid with an offensive odor; [HSDB] Colorless solid; [MSDSonline]


Used as non-systemic acaricide and insecticide for fruits, nuts, berries, cotton, ornamentals, other crops, and livestock; [HSDB]


A cholinesterase inhibitor that may cause CNS effects resulting in convulsions and respiratory depression; Can be absorbed through skin; [ICSC] Highly toxic cholinesterase inhibitor; [CAMEO] A man who attempted suicide by ingestion was brought by friend to emergency room with symptoms including oral and bronchial secretions and respiratory distress requiring intubation; Within an hour health care personal began developing symptoms of poisoning; A nursing assistant who had contact with the patients skin and bodily fluids required intubation and was hospitalized for 9 days; Two nurses who were exposed only by inhalation in close proximity to the patient developed symptoms including confusion, nausea, abdominal cramps, and dyspnea; Many poisoning cases have been reported from the use of animal dips and shampoos by pet owners, groomers, and veterinary assistants; [HSDB] Not likely to be teratogenic, based on animal studies; [REPROTOX] 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]


Cancelled--no longer registered for residential pesticide uses (domestic pets and home gardens) in the US; [HSDB]

Reference Link

EPA Pesticide Chemical Search

Exposure Assessment

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]

Vapor Pressure

4.9E-7 mm Hg

Lethal Concentration

LC50 (rat) > 152 mg/m3

Explanatory Notes

The Guide in the Emergency Response Guidebook is for "Organophosphorus pesticide, solid, toxic."

Reference Link

INCHEM JMPR: Phosmet (addendum) - 2003

Adverse Effects

Hepatotoxin, Secondary

Other Poison


Links to Other NLM Databases
Health Studies

Human Health Effects from Hazardous Substances Data Bank:

Toxicity Information


Chemical Information

Search ChemIDplus

Biomedical References

Search PubMed

Related Information in HazMap

Occupational diseases associated with exposure to this agent:


Industrial Processes with risk of exposure: