Phosphorothioic acid, O,O-dimethyl O-(2-(ethylthio)ethyl) ester, mixed with O,O-dimethyl S-(2-(ethylthio)ethyl) ester (7:3)

RTECS #

TG1760000

CAS #

8022-00-2
See: NMAM or OSHA Methods

Updated

September 2013

Molecular Weight

230.30

Molecular Formula

C₆H₁₅O₃PS₂

Synonyms

Bayer 21/116
Demeton methyl
Duratox
Metasystox
Methyl demeton
Methyl demeton (ACGIH)
Methyl systox
Methyl-mercaptophos
Methylmerkaptofos (Czech)
S(and O)-2-(Ethylthio)ethyl O,O-dimethyl phosphorothioate

Reproductive Effects Data and References

Route/Organism	Dose	Effect	Reference
inhalation/rat	200 ng/m³/24H (1-22D pregnant)	Reproductive: Effects on embryo or fetus: Fetotoxicity (except death, e.g., stunted fetus) Reproductive: Other developmental abnormalities Reproductive: Specific developmental abnormalities: Musculoskeletal system	HYSAAV 36(1),34,1971
inhalation/rat	700 ng/m³/24H (1-22D pregnant)	Reproductive: Effects on fertility: Pre- implantation mortality (e.g., reduction in number of implants per female; total number of implants per corpora lutea)	HYSAAV 36(1),34,1971
inhalation/rat	100 µg/m³/24H (1-22D pregnant)	Reproductive: Effects on fertility: Litter size (e.g., # fetuses per litter; measured before birth)	HYSAAV 36(1),34,1971
inhalation/rat	500 µg/m³/24H (1-22D pregnant)	Reproductive: Specific developmental abnormalities: Central nervous system Reproductive: Effects on newborn: Sex ratio	HYSAAV 36(1),34,1971

Acute Toxicity Data and References

Route/Organism	Dose	Effect	Reference
inhalation/cat	Lowest published lethal concentration: 20 mg/m³/4H		85GMAT -,85,1982
intravenous/rat	lethal dose (50 percent kill): 12 mg/kg		BJIMAG 15,158,1958
oral/cat	lowest published lethal dose: 30 mg/kg		85GMAT -,85,1982
oral/mouse	lethal dose (50 percent kill): 26 mg/kg		85JDAH -,197,1974
oral/rabbit	lethal dose (50 percent kill): 46 mg/kg		GISAAA 27(8),97,1962
oral/rat	lethal dose (50 percent kill): 75 mg/kg		FATOAO 22,259,1959
skin/rabbit	lowest published lethal dose: 75 mg/kg		GTPZAB 2(5),7,1958
skin/rat	lethal dose (50 percent kill): 300 mg/kg		WRPCA2 9,119,1970
unreported route/mammal (species unspecified)	lethal dose (50 percent kill): 80 mg/kg		30ZDA9 -,346,1971
unreported route/mouse	lethal dose (50 percent kill): 3500 µg/kg	Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase	PCJOAU 3,508,1969

Other Multiple Dose Data and References

Route/Organism	Dose	Effect	Reference
oral/cat	lowest published toxic dose: 470 mg/kg/94D- intermittent	Blood: Changes in serum composition (e.g. TP, bilirubin, cholesterol) Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase Related to Chronic Data: Death in the "MULTIPLE DOSE" data type field	FATOAO 22,559,1959
oral/rat	lowest published toxic dose: 404 mg/kg/78W- intermittent	Brain and Coverings: Other degenerative changes Liver: Other changes Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase	FATOBP 8,122,1973
oral/rat	lowest published toxic dose: 1230 mg/kg/18W- intermittent	Blood: Changes in serum composition (e.g. TP, bilirubin, cholesterol) Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase Related to Chronic Data: Death in the "MULTIPLE DOSE" data type field	FATOAO 22,559,1959

Reviews

Organization	Standard	Reference
American Conference of Governmental Industrial Hygienists (ACGIH)	Threshold Limit Value-time-weighted average 0.05 mg/m³ (inhal, vapor, skin)	DTLVS* TLV/BEI,2013

Standards and Regulations

Organization	Standard	Reference
Mine Safety and Health Administration (MSHA) STANDARD-air	time-weighted average 0.5 mg/m³ (skin)	DTLVS* 3,165,1971
Occupational Exposure Limit IN ARGENTINA, BULGARIA, COLOMBIA, JORDAN check ACGIH TLV;
Occupational Exposure Limit IN SINGAPORE, VIETNAM check ACGIH TLV
Occupational Exposure Limit-AUSTRALIA	time-weighted average 0.5 mg/m³, JUL2008
Occupational Exposure Limit-AUSTRIA	MAK-TMW 0.05 ppm (0.5 mg/m³);KZW 0.5 ppm (5 mg/m³), skin, 2007
Occupational Exposure Limit-BELGIUM	time-weighted average 0.5 mg/m³, Skin, MAR2002
Occupational Exposure Limit-DENMARK	time-weighted average 0.05 ppm (0.5 mg/m³), skin, MAY2011
Occupational Exposure Limit-FRANCE	VME 0.5 mg/m³, Skin, FEB2006
Occupational Exposure Limit-GERMANY	MAK 0.5 ppm (4.8 mg/m³), 2011
Occupational Exposure Limit-ICELAND	time-weighted average 0.05 ppm (0.5 mg/m³), skin, NOV2011
Occupational Exposure Limit-KOREA	time-weighted average 0.5 mg/m³, skin, 2006
Occupational Exposure Limit-MEXICO	time-weighted average 0.5 mg/m³;short term exposure limit 1.5 mg/m³ (skin), 2004
Occupational Exposure Limit-NEW ZEALAND	time-weighted average 0.5 mg/m³, skin, JAN2002
Occupational Exposure Limit-PERU	time-weighted average 0,5 mg/m³, JUL2005
Occupational Exposure Limit-RUSSIA	short term exposure limit 0.1 mg/m³, Skin, JUN2003
Occupational Exposure Limit-SWITZERLAND	MAK-week 0.05 ppm (0.5 mg/m³), skin, JAN2011
Occupational Exposure Limit-THE NETHERLANDS	MAC-TGG 0.5 mg/m³, Skin, 2003

NIOSH Documentation and Surveillance

Organization	Standard	Reference
National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Level TO METHYL DEMETON-air	10H time-weighted average 0.5 mg/m³ (Sk)	NIOSH* DHHS #92-100,1992
National Occupational Hazard Survey 1974	Hazard Code 26540; Number of Industries 1; Total Number of Facilities 165; Number of Occupations 2; Total Number of Employees Exposed 331

Page last reviewed: November 16, 2018

Content source: National Institute for Occupational Safety and Health