Agent Name
CAS Number
Major Category
Pirimiphos-methyl formula graphical representation
2-Diethylamino-6-methylpyrimidin-4-yl dimethyl phosphorothionate; Actelic; Actellic; Actellifog; Aktelik; Aktellik; BLEX; Fosforan pirimidyny [Polish]; Methylpirimiphos; O,O-Dimethyl O-(2-(diethylamino)-6-methyl-4-pyrimidinyl) phosphorothioate; O-(2-Diethylamino-6-methylpyrimidin-4-yl) O,O-dimethyl phosphorothioate; OMS 1424; PP511; Pirimifosmethyl; Pirimiphos methyl; Primiphos-methyl; Plant protection PP511; Pyridimine phosphate; Pyrimiphos methyl; Pyrimiphos-methyl [ISO-French]; R 33986; Silosan; Sybol 2; O-(2-(Diethylamino)-6-methyl-4-pyrimidinyl) O,O-dimethylphosphorothioate; [ChemIDplus]
Organophosphate Insecticides
Straw colored liquid; mp = 15-18 deg C (technical grade); [HSDB]
Used as insecticide and veterinary ectoparasiticide; [Merck Index] Used to control insects and mites in vegetables, warehouses, stored grain, animal housings, and domestic and industrial areas; [HSDB] Registered in the US as general use classification insecticide for sorghum and corn (seed and stored), cattle ear tags, and fogging iris bulbs; [Reference #1]
Effects observed in two week study with rats include weight loss, decreased hemoglobin, and reticulocytosis; Minor reversible bile duct proliferation and liver damage observed in 90 day feeding study with dogs; Caused minor skin and eye irritation in rabbits; No evidence of skin sensitization in guinea pigs; [HSDB] “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]
Reference Link #1
Biomedical References

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
1.5E-05 mm Hg
Lethal Concentration
LC (rat) > 5040 mg/m3/4h
Reference Link #2

Adverse Effects

Hepatoxic (a) from occupational exposure (secondary effect) or (b) in animal studies or in humans after ingestion
Other Poison

Diseases, Processes, and Activities Linked to This Agent


Occupational diseases associated with exposure to this agent:


Industrial Processes with risk of exposure: