NIOSH logo and tagline

Acetimidic acid, thio-N-((methylcarbamoyl)oxy)-, methyl ester

RTECS #
AK2975000
CAS #
16752-77-5
See: NMAM or OSHA Methods
Updated
September 2018
Molecular Weight
162.23
Molecular Formula
C5H10N2O2S
Synonyms
1N-X1179-412
2-Methylthio-acetaldehyd-O-(methylcarbamoyl)-oxim (German)
2-Methylthio-propionaldehyd-O-(methylcarbamoyl)-oxim (German)
3-Thiabutan-2-one, O-(methylcarbamoyl)oxime
Acetimidic acid, N-((methylcarbamoyl)oxy)thio-, methyl ester (8CI)
Acetimidothioic acid, methyl-, N-(methylcarbamoyl) ester
DPX-X1179-412
Du Pont insecticide 1179
Dupont 1179
ENT 27,341
Ethanimidothioic acid, N-(((methylamino)carbonyl)oxy)-, methyl ester (9CI)
IN 1179
Insecticide 1,179
Lannate
Lannate 10L candidate
Lannate L
Lannate LV
Mesomile
Methomex
Methomyl
Methomyl (ACGIH)
Methyl N-(((methylamino)carbonyl)oxy)ethanimidothioate
Methyl O-(methylcarbamoyl)thiolacethohydroxamate
Methyl-N-((methylcarbamoyl)oxy)thioacetimidate
Metomil (Italian)
N-(((Methylamino)carbonyl)oxy)ethanimidothioic acid methyl ester
N-((Methylcarbamoyl)oxy)thioacetimidic acid methyl ester
NU-Bait II
Nudrin
RCRA waste number P066
SD 14999
S-Methyl N-(methylcarbamoyloxy) thioacetimidate
S-Methyl N-(methylcarbamoyloxy)thioacetimidate
WL 18236

Mutation Data and Reference

System TestRoute/Organism/TissueDoseReference
Cytogenetic Analysislymphocyte/human180 µmol/LEMMUEG 23,306,1994
Cytogenetic Analysisoral/mouse20 mg/kgENVRAL 42,362,1987
Cytogenetic Analysisovary/hamster1.3 mg/L/2HFCTOD7 45,928,2007
DNA Damageother cell types/Drosophila melanogaster4 mmol/L/48HFCTOD7 53,352,2013
DNA DamageHeLa cell/human8 mmol/L/24HFCTOD7 53,352,2013
DNA Damagekidney/human8 mmol/L/24HFCTOD7 53,352,2013
DNA DamageHeLa cell/human8 mmol/L/30MFCTOD7 53,352,2013
DNA Damageintraperitoneal/mouse5 mg/kgEMMUEG 24,235,1994
DNA Damageintraperitoneal/mouse10 mg/kgEMMUEG 24,235,1994
DNA Damagelymphocyte/human500 µmol/LEMMUEG 23,306,1994
DNA Damagelymphocyte/human1 mmol/LEMMUEG 23,306,1994
micronucleus testlymphocyte/human10 µmol/LEMMUEG 23,306,1994
mutation in microorganisms/Saccharomyes cerevisiae50 ppm (-enzymatic activation step)RSTUDV 6,161,1976
sperm morphologyoral/mouse20 mg/kgENVRAL 42,362,1987

Reproductive Effects Data and References

Route/OrganismDoseEffectReference
oral/rat 32.5 mg/kg (65D male)Reproductive: Paternal effects: Spermatogenesis (including genetic material, sperm morphology, motility, and count)

Reproductive: Paternal effects: Testes, epididymis, sperm duct

Reproductive: Paternal effects: Prostate, seminal vesicle, Cowper's gland, accessory glands
FCTOD7 48,3221,2010
oral/rat 32.5 mg/kg (65D male)Reproductive: Effects on fertility: Female fertility index (e.g., # females pregnant per # sperm positive females; # females pregnant per # females mated)FCTOD7 48,3221,2010

Acute Toxicity Data and References

Route/OrganismDoseEffectReference
In Vitro/Human, HeLa cell Inhibitor Concentration (50 percent kill): 21.46 mmol/L/24HIn Vitro Toxicity Studies: Cell viability (dye exclusion): trypan blue assay etc.FCTOD7 53,352,2013
In Vitro/Human, HeLa cell Inhibitor Concentration Low: 5 mmol/L/12HIn Vitro Toxicity Studies: Cell viability (dye exclusion): trypan blue assay etc.FCTOD7 53,352,2013
In Vitro/Human, kidney Inhibitor Concentration Low: 10 mmol/L/12HIn Vitro Toxicity Studies: Cell viability (dye exclusion): trypan blue assay etc.FCTOD7 53,352,2013
In Vitro/Human, kidney Inhibitor Concentration (50 percent kill): 8.2 mmol/L/24HIn Vitro Toxicity Studies: Cell viability (dye exclusion): trypan blue assay etc.FCTOD7 53,352,2013
In Vitro/ntbInhibitor Concentration Low: 10 mmol/L/12HIn Vitro Toxicity Studies: Cell viability (dye exclusion): trypan blue assay etc.FCTOD7 53,352,2013
In Vitro/ntbInhibitor Concentration (50 percent kill): 9.74 mmol/L/48HIn Vitro Toxicity Studies: Cell viability (dye exclusion): trypan blue assay etc.FCTOD7 53,352,2013
inhalation/duck lethal concentration (50 percent kill): 1890 ppmTXAPA9 40,1,1977
inhalation/quail lethal concentration (50 percent kill): 3680 ppmTXAPA9 40,1,1977
inhalation/rat lethal concentration (50 percent kill): 77 ppm/4HEye: Lacrimation

Behavioral: Tremor

Lung, Thorax, or Respiration: Dyspnea
TXAPA9 40,1,1977
inhalation/rat lethal concentration (50 percent kill): 450 mg/m3HBPTO* 2,1094,2001
inhalation/rat lethal concentration (50 percent kill): 0.3 gm/m3/4HENTOX* -,57,2005
intraperitoneal/mouse lowest published toxic dose: 5.2 mg/kgBehavioral: Convulsions or effect on seizure thresholdTOSCF2 72,289,2003
intraperitoneal/mouse lowest published lethal dose: 6.4 mg/kgBehavioral: Convulsions or effect on seizure thresholdTOSCF2 72,289,2003
intraperitoneal/rat lowest published toxic dose: 2.3 mg/kgLung, Thorax, or Respiration: Respiratory depression

Nutritional and Gross Metabolic: Body temperature decrease
CTOXAO 47,725,2009
intraperitoneal/rat lowest published toxic dose: 7.5 mg/kgBrain and Coverings: Changes in surface EEG

Behavioral: Convulsions or effect on seizure threshold

Behavioral: Ataxia
TXAPA9 219,122,2007
intraperitoneal/rat lowest published toxic dose: 2.3 mg/kgLung, Thorax, or Respiration: Respiratory depression

Lung, Thorax, or Respiration: Other changes

Nutritional and Gross Metabolic: Body temperature decrease
TOXID9 -,444,2009
intraperitoneal/rat lowest published toxic dose: 2.3 mg/kgBrain and Coverings: Other degenerative changes

Lung, Thorax, or Respiration: Respiratory depression

Nutritional and Gross Metabolic: Body temperature decrease
FCLPH* 23(Suppl 1),8,2009
intraperitoneal/rat lethal dose (50 percent kill): 6290 µg/kgBehavioral: Tremor

Behavioral: Convulsions or effect on seizure threshold

Behavioral: Straub Tail
ETOPFR 7,119,1999
oral/chicken lethal dose (50 percent kill): 28 mg/kgEye: Lacrimation

Behavioral: Convulsions or effect on seizure threshold

Lung, Thorax, or Respiration: Dyspnea
TXAPA9 40,1,1977
oral/chicken lethal dose (50 percent kill): 28 mg/kgENTOX* -,57,2005
oral/Dog lethal dose (50 percent kill): 20 mg/kg85INA8 6,906,1991
oral/duck lethal dose (50 percent kill): 15 mg/kgSHELL*
oral/guinea pig lowest published lethal dose: 15 mg/kgTXAPA9 40,1,1977
oral/human lowest published lethal dose: 12 mg/kgBrain and Coverings: Other degenerative changes

Peripheral Nerve and Sensation: Flaccid paralysis without anesthesia (usually neuromuscular blockage)

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase
HBPTO* 2,1097,2001
oral/monkey lowest published lethal dose: 40 mg/kgTXAPA9 40,1,1977
oral/mouse lethal dose (50 percent kill): 10 mg/kgJAFCAU 26,550,1978
oral/pigeon lethal dose (50 percent kill): 10 mg/kgASTTA8 (680),157,1979
oral/quail lethal dose (50 percent kill): 23700 µg/kgASTTA8 (680),157,1979
oral/rat lethal dose (50 percent kill): 12 mg/kgHBPTO* 2,1094,2001
oral/rat lethal dose (50 percent kill): 20 mg/kgBehavioral: Tremor

Cardiac: Change in rate

Skin and Appendages: Other: Sweating
FCTOD7 48,3221,2010
oral/rat lowest published toxic dose: 0.6 mg/kgBrain and Coverings: Other degenerative changes

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase
TOXID9 44,395,2005
oral/rat lowest published toxic dose: 0.1 mg/kgBehavioral: Change in motor activity (specific assay)TOXID9 44,397,2005
oral/rat lowest published toxic dose: 0.25 mg/kgBiochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesteraseTXCYAC 331,1,2015
oral/wild bird lethal dose (50 percent kill): 10 mg/kgTXAPA9 21,315,1972
skin/rabbit lethal dose (50 percent kill): 556 mg/kgHBPTO* 2,1094,2001
skin/rat lethal dose (50 percent kill): 1000 mg/kgHBPTO* 2,1094,2001
subcutaneous/rat lethal dose (50 percent kill): 9 mg/kgTXAPA9 25,569,1973
unreported route/rat lethal dose (50 percent kill): 17 mg/kgVCVGK* -,512,1994

Other Multiple Dose Data and References

Route/OrganismDoseEffectReference
oral/Dog lowest published toxic dose: 18200 mg/kg/2Y- continuousKidney, Ureter, and Bladder: Changes in tubules (including acute renal failure, acute tubular necrosis)

Blood: Changes in bone marrow not included in above

Related to Chronic Data: Death in the "MULTIPLE DOSE" data type field
TXAPA9 40,1,1977
oral/rat lowest published toxic dose: 32.5 mg/kg/65D- intermittentEndocrine: Androgenic

Related to Chronic Data: Changes in prostate weight

Related to Chronic Data: Changes in testicular weight
FCTOD7 48,3221,2010
oral/rat lowest published toxic dose: 14700 µg/kg/5D- intermittentPeripheral Nerve and Sensation: Structural change in nerve or sheath

Liver: Other changes

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase
WDZAEK 6,37,1992
oral/rat lowest published toxic dose: 102 mg/kg/60D- intermittentLiver: Other changes

Blood: Changes in serum composition (e.g. TP, bilirubin, cholesterol)

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Other transferases
JDGRAX 22,259,1998
oral/rat lowest published toxic dose: 15960 mg/kg/95W- continuousBlood: Changes in bone marrow not included in above

Nutritional and Gross Metabolic: Weight loss or decreased weight gain

Related to Chronic Data: Changes in testicular weight
TXAPA9 40,1,1977
oral/rat lowest published toxic dose: 264 mg/kg/33D- intermittentBrain and Coverings: Other degenerative changes

Blood: Changes in serum composition (e.g. TP, bilirubin, cholesterol)

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase
CMSHAF 23,375,1991
oral/rat lowest published toxic dose: 9 mg/kg/90D- intermittentNutritional and Gross Metabolic: Weight loss or decreased weight gainJDGRAX 18,145,1989
skin/rabbit lowest published toxic dose: 3 gm/kg/3W- intermittentBehavioral: Somnolence (general depressed activity)

Lung, Thorax, or Respiration: Dyspnea

Related to Chronic Data: Death in the "MULTIPLE DOSE" data type field
TXAPA9 40,1,1977

Reviews

OrganizationStandardReference
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-time-weighted average 2.5 mg/m3DTLVS* TLV/BEI,2013
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-Not classifiable as a human carcinogenDTLVS* TLV/BEI,2013
TOXICOLOGY REVIEWMUREAV 557,109,2004
TOXICOLOGY REVIEWMUTAEX 21,93,2006
TOXICOLOGY REVIEWENTOX* -,57,2005
TOXICOLOGY REVIEWJTEHD6 7,1,2004
TOXICOLOGY REVIEWFEREAC 71,43906,2006
TOXICOLOGY REVIEWHTOPA* 1,501,2002
TOXICOLOGY REVIEWFEREAC 73,47184,2008
TOXICOLOGY REVIEWMUTAEX 21,343,2006
TOXICOLOGY REVIEWMUREAV 721,27,2011
TOXICOLOGY REVIEWTXAPA9 258,309,2012
TOXICOLOGY REVIEWTOLED5 230,146,2014
TOXICOLOGY REVIEWMUREAV 767,67,2016
TOXICOLOGY REVIEWTXAPA9 268,157,2013
TOXICOLOGY REVIEWFCTOD7 83,300,2015
TOXICOLOGY REVIEWFCTOD7 105,456,2017

Standards and Regulations

OrganizationStandardReference
Environmental Protection Agency (EPA) Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) 1988 PESTICIDE SUBJECT TO REGISTRATION OR RE-REGISTRATIONFEREAC 54,7740,1989
Environmental Protection Agency (EPA) Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) 1998 STATUS OF PESTICIDESSupportedRBREV* -,131,1998
Occupational Exposure Limit IN ARGENTINA, BULGARIA, COLOMBIA, JORDAN check ACGIH TLV;
Occupational Exposure Limit IN SINGAPORE, VIETNAM check ACGIH TLV
Occupational Exposure Limit-AUSTRALIAtime-weighted average 2.5 mg/m3, JUL2008
Occupational Exposure Limit-AUSTRIAMAK-TMW 2.5 mg/m3;KZW 5 mg/m3, inhal, skin, 2007
Occupational Exposure Limit-BELGIUMtime-weighted average 2.5 mg/m3, MAR2002
Occupational Exposure Limit-DENMARKtime-weighted average 2.5 mg/m3, skin, MAY2011
Occupational Exposure Limit-FRANCEVME 2.5 mg/m3, Skin, FEB2006
Occupational Exposure Limit-ICELANDtime-weighted average 2.5 mg/m3, skin, NOV2011
Occupational Exposure Limit-KOREAtime-weighted average 2.5 mg/m3, 2006
Occupational Exposure Limit-MEXICOtime-weighted average 2.5 mg/m3, 2004
Occupational Exposure Limit-NEW ZEALANDtime-weighted average 2.5 mg/m3, JAN2002
Occupational Exposure Limit-NORWAYtime-weighted average 2.5 mg/m3, JAN1999
Occupational Exposure Limit-PERUtime-weighted average 2,5 mg/m3, JUL2005
Occupational Exposure Limit-RUSSIAshort term exposure limit 0.5 mg/m3, MAR2004
Occupational Exposure Limit-SWITZERLANDMAK-week 2.5 mg/m3, inhal, skin, JAN2011
Occupational Exposure Limit-THE NETHERLANDSMAC-TGG 2.5 mg/m3, Skin, 2003

NIOSH Documentation and Surveillance

OrganizationStandardReference
National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Level TO METHOMYL-air10H time-weighted average 2.5 mg/m3NIOSH* DHHS #92-100,1992
National Occupational Exposure Survey 1983Hazard Code B0027; Number of Industries 1; Total Number of Facilities 15; Number of Occupations 1; Total Number of Employees Exposed 2367; Total Number of Female Employees Exposed 1288

Status in Federal Agencies

OrganizationReference
EPA GENETOX PROGRAM 1988, Inconclusive: B subtilis rec assay; E coli polA without S9
EPA GENETOX PROGRAM 1988, Inconclusive: Histidine reversion-Ames test
EPA GENETOX PROGRAM 1988, Negative: D melanogaster Sex-linked lethal
EPA GENETOX PROGRAM 1988, Negative: In vitro UDS-human fibroblast; TRP reversion
EPA GENETOX PROGRAM 1988, Negative: S cerevisiae-homozygosis
EPA TSCA Section 8(d) unpublished health/safety studies
EPA TSCA TEST SUBMISSION (TSCATS) DATA BASE, JANUARY 2001
On EPA IRIS database
Page last reviewed: November 16, 2018