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Registry of Toxic Effects of Chemical Substances (RTECS)

Phosphorothioic acid, O,O-dimethyl O-(4-(methylthio)-m-tolyl) ester

RTECS #

TF9625000

CAS #

55-38-9

Updated

September 201

Molecular Weight

278.34

Molecular Formula

C10H15O3PS2

Synonyms

4-Methylmercapto-3-methylphenyl dimethyl thiophosphate
B 29493
BAY 29493
Baycid
Bayer 29493
Bayer 9007
Bayer S-1752
Baytex
ENT 25,540
Entex
Fenthion
Fenthion (ACGIH)
Fenthion 4E
Fenthion-methyl
Lebaycid
m-Cresol, 4-(methylthio)-, O-ester with O,O-dimethyl phosphorothioate
Mercaptophos
MPP (pesticide)
NCI-C08651
O,O-Dimethyl O-(3-methyl-4-methylmercaptophenyl)phosphorothioate
O,O-Dimethyl O-(4-(methylthio)-m-tolyl) phosphorothioate
O,O-Dimethyl O-(4-methylthio-3-methylphenyl) phosphorothioate
O,O-Dimethyl O-3-methyl-4-methylthiophenyl phosphorothioate
O,O-Dimethyl O-4-(methylmercapto)-3-methylphenyl phosphorothioate
O,O-Dimethyl-O-(3-methyl-4-methylthio-fenyl)-monothiofosfaat (Dutch)
O,O-Dimethyl-O-(3-methyl-4-methylthiophenyl)-monothiophosphat (German)
O,O-Dimethyl-O-(3-methyl-4-methylthio-phenyl)-thionophosphat (German)
O,O-Dimethyl-O-4-(methylmercapto)-3-methylphenyl thiophosphate
O,O-Dimetil-O-(3-metil-4-metiltio-fenil)-monotiofosfato (Italian)
OMS 2
Phosphorothioic acid O,O-dimethyl O-(3-methyl-4-(methylthio)phenyl) ester
Queletox
S 1752
Spotton
Sulfidophos
Talodex
Thiophosphate de O,O-dimethyle et de O-(3-methyl-4-methylthiophenyle) (French)
Tiguvon

Mutation Data and Reference

System TestRoute/Organism/TissueDoseReference
mutation in microorganisms/Salmonella typhimurium333 µg/plate (-enzymatic activation step)ENMUDM 8(Suppl 7),1,1986
sister chromatid exchangelung/hamster40 mg/LENMUDM 4,621,1982

Reproductive Effects Data and References

Route/OrganismDoseEffectReference
intraperitoneal/mouse 40 mg/kg (11D pregnant)Reproductive: Effects on embryo or fetus: Fetotoxicity (except death, e.g., stunted fetus)

Reproductive: Specific developmental abnormalities: Craniofacial (including nose and tongue)

Reproductive: Specific developmental abnormalities: Musculoskeletal system
TXAPA9 24,324,1973
oral/rat 10 mg/kg (6-15D pregnant)Reproductive: Other effects on femaleTIHEEC 14,869,1998
oral/mouse 1050 mg/kg (multigenerations)Reproductive: Effects on fertility: Female fertility index (e.g., # females pregnant per # sperm positive females; # females pregnant per # females mated)

Reproductive: Effects on newborn: Viability index (e.g., # alive at day 4 per # born alive)

Reproductive: Effects on newborn: Weaning or lactation index (e.g., # alive at weaning per # alive at day 4)
TXAPA9 26,29,1973

Tumorigenic Data and References

Route/OrganismDoseEffectReference
oral/mouse lowest published toxic dose: 1730 mg/kg/103W- continuousTumorigenic: Equivocal tumorigenic agent by RTECS criteria

Skin and Appendages: Tumors
NCITR* NCI-TR-103,1979

Acute Toxicity Data and References

Route/OrganismDoseEffectReference
inhalation/guinea pig Lowest published lethal concentration: 1 gm/m3/2H85GYAV -,27,1971
inhalation/mouse Lowest published lethal concentration: 1 gm/m3/2H85GYAV -,27,1971
inhalation/rabbit Lowest published lethal concentration: 1 gm/m3/2H85GYAV -,27,1971
inhalation/rat lethal concentration (50 percent kill): 800 mg/m3/4H85INA8 6,646,1991
intracerebral/mouse lethal dose (50 percent kill): 50 mg/kgPCBPBS 8,302,1978
intramuscular/Dog lethal dose (50 percent kill): 40 mg/kgVMRVAN (2-3),273,1967
intramuscular/domestic animal lethal dose (50 percent kill): 46 mg/kgBiochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Reactivates cholinesteraseVETNAL 54(12),94,1978
intramuscular/mammal (species unspecified) lethal dose (50 percent kill): 46200 µg/kgBehavioral: Somnolence (general depressed activity)

Behavioral: Food intake (animal)

Behavioral: Muscle contraction or spasticity
VETNAL 54(12),94,1978
intraperitoneal/chicken lethal dose (50 percent kill): 20 mg/kgEQSFAP 3,173,1974
intraperitoneal/guinea pig lethal dose (50 percent kill): 310 mg/kgTXAPA9 6,86,1964
intraperitoneal/mouse lowest published toxic dose: 300 mg/kgBrain and Coverings: Other degenerative changesTOLED5 135,89,2002
intraperitoneal/mouse lethal dose (50 percent kill): 125 mg/kgTXAPA9 6,86,1964
intraperitoneal/rat lethal dose (50 percent kill): 260 mg/kgTXAPA9 6,86,1964
intravenous/mouse lethal dose (50 percent kill): 320 mg/kgCSLNX* NX#00142
oral/chicken lethal dose (50 percent kill): 20 mg/kgEQSFAP 3,173,1974
oral/duck lethal dose (50 percent kill): 5900 µg/kgDOEAAH 35,25,1979
oral/guinea pig lethal dose (50 percent kill): 260 mg/kgTXAPA9 6,86,1964
oral/mammal (species unspecified) lethal dose (50 percent kill): 105 mg/kgBehavioral: Somnolence (general depressed activity)

Behavioral: Food intake (animal)

Behavioral: Muscle contraction or spasticity
VETNAL 54(12),94,1978
oral/man lowest published toxic dose: 1429 µL/kgLung, Thorax, or Respiration: Other changes

Kidney, Ureter, and Bladder: Other changes

Skin and Appendages: Other: Sweating
JJAMA* 14,789,1990
oral/man lowest published toxic dose: 3571 µL/kgEye: Miosis (pupilliary constriction)

Behavioral: General anesthetic

Behavioral: Convulsions or effect on seizure threshold
YAKUD5 32,1456,1990
oral/man lowest published toxic dose: 643 µL/kgPeripheral Nerve and Sensation: Fasciculations

Behavioral: Ataxia

Cardiac: Pulse rate decreased with fall in BP
HETOEA 14,600,1995
oral/man lowest published toxic dose: 257 mg/kgCardiac: Pulse rate increased without fall in BP

Gastrointestinal: Hypermotility, diarrhea

Gastrointestinal: Nausea or vomiting
JTCTDW 19,425,1982
oral/mouse lethal dose (50 percent kill): 88100 µg/kgHOEKAN 30,53,1980
oral/pigeon lethal dose (50 percent kill): 1780 µg/kgASTTA8 (680),157,1979
oral/quail lethal dose (50 percent kill): 11 mg/kgTXAPA9 20,57,1971
oral/rabbit lethal dose (50 percent kill): 150 mg/kgBehavioral: Muscle weakness

Gastrointestinal: Changes in structure or function of salivary glands

Kidney, Ureter, and Bladder: Other changes
BWHOA6 29,205,1963
oral/rabbit lowest published toxic dose: 150 mg/kgLung, Thorax, or Respiration: Structural or functional change in trachea or bronchi

Lung, Thorax, or Respiration: Emphysema

Blood: Hemorrhage
JTCTDW 46,711,2008
oral/rat lethal dose (50 percent kill): 180 mg/kgKSKZAN 16(2),59,1978
oral/wild bird lethal dose (50 percent kill): 1300 µg/kgTXAPA9 21,315,1972
oral/woman lowest published toxic dose: 525 mg/kgEye: Miosis (pupilliary constriction)

Behavioral: Muscle contraction or spasticity

Lung, Thorax, or Respiration: Respiratory depression
HETOEA 9,187,1990
oral/woman lowest published toxic dose: 1200 µL/kgBehavioral: Coma

Cardiac: Pulse rate decreased with fall in BP

Gastrointestinal: Hypermotility, diarrhea
HETOEA 14,600,1995
skin/duck lethal dose (50 percent kill): 44 mg/kgTXAPA9 47,451,1979
skin/mouse lethal dose (50 percent kill): 500 mg/kgOYYAA2 1,74,1967
skin/rat lethal dose (50 percent kill): 330 mg/kgBehavioral: Tremor

Behavioral: Convulsions or effect on seizure threshold

Behavioral: Excitement
TXAPA9 2,88,1960
subcutaneous/mouse lethal dose (50 percent kill): 144 mg/kgOYYAA2 1,74,1967
subcutaneous/rat lowest published toxic dose: 0.8 gm/kgBrain and Coverings: Other degenerative changes

Lung, Thorax, or Respiration: Other changes

Liver: Other changes
BCLPT* 100,308,2007
subcutaneous/rat lowest published toxic dose: 0.8 gm/kgCardiac: Cardiomyopathy including infarction

Biochemical: Metabolism (intermediary): Other proteins

Biochemical: Metabolism (intermediary): Effect on inflammation or mediation of inflammation
JTCTDW 46,67,2008
subcutaneous/rat lowest published toxic dose: 0.8 gm/kgGastrointestinal: Changes in structure or function of exocrine pancreas

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

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Multiple enzyme effects
JTCTDW 46,141,2008
unreported route/human lowest published lethal dose: 50 mg/kg85INA8 5,267,1986

Other Multiple Dose Data and References

Route/OrganismDoseEffectReference
intraperitoneal/rat lowest published toxic dose: 1200 mg/kg/60D- continuousRelated to Chronic Data: Death in the "MULTIPLE DOSE" data type fieldTXAPA9 6,86,1964
oral/domestic bird lowest published toxic dose: 7500 µg/kg/5D- continuousBehavioral: Food intake (animal)

Nutritional and Gross Metabolic: Weight loss or decreased weight gain

Related to Chronic Data: Death in the "MULTIPLE DOSE" data type field
AECTCV 11,617,1982
oral/rat lowest published toxic dose: 172 mg/kg/6D- intermittentPeripheral Nerve and Sensation: Structural change in nerve or sheath

Blood: Changes in bone marrow not included in above

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase
ZYYZEW 2,126,1988
skin/chicken lowest published toxic dose: 35 mg/kg/7D- intermittentBehavioral: Ataxia

Nutritional and Gross Metabolic: Weight loss or decreased weight gain

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Other esterases
JTEHD6 21,455,1987
skin/chicken lowest published toxic dose: 24 mg/kg/24W- intermittentBlood: Changes in serum composition (e.g. TP, bilirubin, cholesterol)

Musculoskeletal: Other changes

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase
VHTODE 41,302,1999
skin/rat lowest published toxic dose: 380 mg/kg/19D- 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
BWHOA6 29,205,1963
skin/rat lowest published toxic dose: 3225 mg/kg/43W- intermittentBrain and Coverings: Other degenerative changesTXAPA9 104,440,1990
skin/rat lowest published toxic dose: 365 mg/kg/5D- intermittentRelated to Chronic Data: Death in the "MULTIPLE DOSE" data type fieldBWHOA6 29,205,1963
subcutaneous/rat lowest published toxic dose: 5200 mg/kg/1Y- intermittentEye: Retinal changes pigmentary deposition, retinitis, other)

Liver: Other changes

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase
ENVRAL 30,453,1983
subcutaneous/rat lowest published toxic dose: 260 mg/kg/13W- intermittentEye: Retinal changes pigmentary deposition, retinitis, other)TOXID9 15,26,1995
unreported route/rat lowest published toxic dose: 3000 mg/kg/40W- intermittentBrain and Coverings: Other degenerative changes

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase
HBPTO* 1,878,2001

Reviews

OrganizationStandardReference
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-time-weighted average 0.05 mg/m3 (inhal, vapor, skin)DTLVS* TLV/BEI,2013
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-Not classifiable as a human carcinogenDTLVS* TLV/BEI,2013
TOXICOLOGY REVIEWRREVAH 46,1,1973
TOXICOLOGY REVIEWCNDQA8 10(3),43,1975
TOXICOLOGY REVIEWRREVAH 63,1,1976
TOXICOLOGY REVIEWMUTAEX 21,93,2006
TOXICOLOGY REVIEWENTOX* -,325,2005
TOXICOLOGY REVIEWENTOX* -,306,2005
TOXICOLOGY REVIEWENTOX* -,308,2005
TOXICOLOGY REVIEWMUREAV 584,1,2005
TOXICOLOGY REVIEWHETOEA 26,321,2007
TOXICOLOGY REVIEWFCTOD7 47,2906,2009
TOXICOLOGY REVIEWFCTOD7 47,2926,2009
TOXICOLOGY REVIEWNTAPM* -,629,1995
TOXICOLOGY REVIEWTOLED5 190,107,2009
TOXICOLOGY REVIEWMUREAV 721,27,2011

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* -,120,1998
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 0.2 mg/m3, JUL2008
Occupational Exposure Limit-AUSTRIAMAK-TMW 0.2 mg/m3;KZW 2 mg/m3, inhal, skin, 2007
Occupational Exposure Limit-BELGIUMtime-weighted average 0.2 mg/m3, Skin, MAR2002
Occupational Exposure Limit-DENMARKtime-weighted average 0.1 mg/m3, skin, MAY2011
Occupational Exposure Limit-GERMANYMAK 0.2 mg/m3, inhal, 2011
Occupational Exposure Limit-ICELANDtime-weighted average 0.1 mg/m3, skin, NOV2011
Occupational Exposure Limit-JAPANOccupational Exposure Limit 0.2 mg/m3, skin, MAY2012
Occupational Exposure Limit-KOREAtime-weighted average 0.2 mg/m3, skin, 2006
Occupational Exposure Limit-NEW ZEALANDtime-weighted average 0.2 mg/m3, skin, JAN2002
Occupational Exposure Limit-PERUtime-weighted average 0,2 mg/m3, JUL2005
Occupational Exposure Limit-POLANDMAC(time-weighted average) 0.2 mg/m3, JAN1999
Occupational Exposure Limit-SWITZERLANDMAK-week 0.1 mg/m3, KZG-week 0.2 mg/m3, inhal, skin, JAN2011
Occupational Exposure Limit-THE NETHERLANDSMAC-TGG 0.1 mg/m3, 2003

NIOSH Documentation and Surveillance

OrganizationStandardReference
National Occupational Exposure Survey 1983Hazard Code X9267; Number of Industries 4; Total Number of Facilities 221; Number of Occupations 6; Total Number of Employees Exposed 2142; Total Number of Female Employees Exposed 442

Status in Federal Agencies

OrganizationReference
EPA GENETOX PROGRAM 1988, Inconclusive: B subtilis rec assay; E coli polA without S9
EPA GENETOX PROGRAM 1988, Inconclusive: D melanogaster Sex-linked lethal
EPA GENETOX PROGRAM 1988, Inconclusive: Histidine reversion-Ames test
EPA GENETOX PROGRAM 1988, Negative: In vitro UDS-human fibroblast; TRP reversion
EPA GENETOX PROGRAM 1988, Negative: S cerevisiae-homozygosis
NCI Carcinogenesis Bioassay (feed);clear evidence:mouseNCITR* NCI-TR-103,1979
NCI Carcinogenesis Bioassay (feed);no evidence:ratNCITR* NCI-TR-103,1979
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