Methyl demeton
Agent Name
Methyl demeton
Alternative Name
Demeton-methyl
CAS Number
8022-00-2
Formula
C6-H15-O3-P-S2
Major Category
Pesticides
Synonyms
Demeton-methyl; Bayer 21/116; Demeton M; Demeton methyl; Demeton-methyl; Metasystox; Metasystox forte; Methyl demeton 25 EC; Methyl mercaptophos; Methyl systox; Methyl-mercaptophos; Methylmerkaptofos [Czech]; Phosphorothioic acid, O-(2-(ethylthio)ethyl) O,O-dimethyl ester, mixt. With S-(2-(ethylthio)ethyl) O,O-dimethyl ester; S(and O)-2-(Ethylthio)ethyl O,O-dimethyl phosphorothioate; [ChemIDplus] UN3018
Category
Organophosphate Insecticides
Description
Oily, colorless to pale-yellow liquid with an unpleasant odor. [insecticide] [Note: Technical grade consists of 2 isomers: thiono & thiolo.]; [NIOSH]
Sources/Uses
Used to kill insects on garden crops, fruit, and hops; [ACGIH]
Comments
It is less toxic than demeton. [ACGIH] A cholinesterase inhibitor that may cause CNS effects; Can be absorbed through skin; [ICSC] “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
Not registered for use in the US; [EPA PPIS]
Biomedical References
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)
0.05 mg/m3, inhalable fraction and vapor
MAK
4.8 mg/m3
Vapor Pressure
0.0004 mm Hg
Lethal Concentration
LCLo (cat) = 20 mg/m3/4hr
Explanatory Notes
The Guide in the Emergency Response Guidebook is for "Organophosphorus pesticide, liquid, toxic."
Adverse Effects
Other Poison
Organophosphate
Diseases, Processes, and Activities Linked to This Agent
Diseases
Occupational diseases associated with exposure to this agent:
Processes
Industrial Processes with risk of exposure: