o-Toluidine

RTECS #

XU2975000

CAS #

95-53-4
See: NMAM or OSHA Methods

Updated

March 2019

Molecular Weight

107.17

Molecular Formula

C₇H₉N

Synonyms

1-Amino-2-methylbenzene
1-Methyl-2-aminobenzene
2-Amino-1-methylbenzene
2-Aminotoluene
2-Methyl-1-aminobenzene
2-Methylaniline
2-Methylbenzenamine
2-Toluidine
Aniline, 2-methyl-
Benzenamine, 2-methyl- (9CI)
C.I. 37077
o-Aminotoluene
o-Methylaniline
o-Methylbenzenamine
ortho-Toluidine
o-Toluidin (Czech)
o-Toluidine (ACGIH:OSHA)
o-Toluidyna (Polish)
o-Tolylamine
RCRA waste number U328

Skin and Eye Irritation and References

Route/Organism	Dose	Effect	Reference
eye /rabbit	750 µg/24H	severe	85JCAE -,460,1986
skin /rabbit	10 mg/24H open irritation test	mild	AIHAAP 23,95,1962
skin /rabbit	500 mg/24H	mild	85JCAE -,460,1986

Mutation Data and Reference

System Test	Route/Organism/Tissue	Dose	Reference
body fluid assay	Salmonella typhimurium/rat	300 mg/kg	MUREAV 79,173,1980
body fluid assay	ovary/rat	400 mg/kg	MUREAV 143,263,1985
Cytogenetic Analysis	liver/rat	175 mg/L	PMRSDJ 5,387,1985
Cytogenetic Analysis	liver/hamster	12 mg/L	PMRSDJ 5,397,1985
Cytogenetic Analysis	lung/hamster	1 gm/L	PMRSDJ 5,427,1985
Cytogenetic Analysis	ovary/hamster	250 mg/L	PMRSDJ 5,413,1985
Cytogenetic Analysis	intraperitoneal/mouse	45 mg/kg	HPV300 -,-,2001
DNA Damage	intraperitoneal/mouse	100 mg/kg	HPV300 -,-,2001
DNA Damage	oral/rat	500 mg/kg	HPV300 -,-,2001
DNA Damage	ovary/hamster	20 mmol/L	PMRSDJ 5,367,1985
DNA Damage	other cell types/rat	8 mmol/L/20H	TXCYAC 179,115,2002
DNA Damage	other cell types/human	16 mmol/L/20H	TXCYAC 179,115,2002
DNA Damage	liver/rat	319 mg/L	PMRSDJ 5,353,1985
DNA Damage	oral/mouse	600 mg/kg	MUREAV 440,1,1999
DNA inhibition	intraperitoneal/mouse	20 gm/kg	ARGEAR 51,605,1981
DNA inhibition	HeLa cell/human	4 mmol/L	CRNGDP 13,2389,1992
DNA inhibition	oral/mouse	200 mg/kg	HPV300 -,-,2001
DNA repair	/Escherichia coli	20 µL/plate	JJIND8 62,873,1979
gene conversion and mitotic recombination	/Saccharomyes cerevisiae	378 mg/L	PMRSDJ 5,271,1985
micronucleus test	multiple/non-mammalian species	4 ppm	MUREAV 292,83,1993
micronucleus test	lymphocyte/human	2 mmol/L	MUREAV 291,93,1993
micronucleus test	intraperitoneal/rat	300 mg/kg	MUREAV 583,133,2005
micronucleus test	oral/rat	600 mg/kg	MUREAV 583,133,2005
morphological transform	embryo/mouse	500 mg/L	PMRSDJ 5,659,1985
morphological transform	embryo/hamster	100 mg/L	PMRSDJ 5,665,1985
morphological transform	fibroblast/mouse	300 mg/L/10D	MUREAV 702,100,2010
mutation in mammalian somatic cells	lymphocyte/mouse	10 mg/L	PMRSDJ 5,587,1985
mutation in mammalian somatic cells	lymphocyte/human	450 mg/L	PMRSDJ 5,497,1985
mutation in microorganisms	/Saccharomyes cerevisiae	378 mg/L (+/-enzymatic activation step)	PMRSDJ 5,271,1985
mutation in microorganisms	lymphocyte/human	300 mg/L (+enzymatic activation step)	PMRSDJ 5,497,1985
mutation in microorganisms	/Salmonella typhimurium	40 µg/plate (-enzymatic activation step)	PJABDW 53,34,1977
mutation in microorganisms	/Salmonella typhimurium	250 ng/plate (+enzymatic activation step)	AGSREJ 13,13,1995
mutation in microorganisms	lymphocyte/mouse	12500 µg/L (+enzymatic activation step)	PMRSDJ 5,525,1985
mutation in microorganisms	embryo/mouse	250 mg/L (+enzymatic activation step)	PMRSDJ 5,639,1985
phage inhibition capacity	/Escherichia coli	100 mmol/L	MDMIAZ 31,11,1979
sex chromosome loss and nondisjunction	liver/hamster	60 mg/L	PMRSDJ 5,397,1985
sister chromatid exchange	lymphocyte/human	200 µmol/L	MUREAV 211,77,1989
sister chromatid exchange	liver/rat	21800 µg/L	PMRSDJ 5,387,1985
sister chromatid exchange	intraperitoneal/hamster	200 mg/kg	MUREAV 113,33,1983
sister chromatid exchange	oral/hamster	200 mg/kg	MUREAV 113,33,1983
sister chromatid exchange	ovary/hamster	125 mg/L	PMRSDJ 5,451,1985
sister chromatid exchange	lung/hamster	2500 µmol/L	PMRSDJ 5,469,1985
specific locus test	oral/Drosophila melanogaster	1 mmol/L	PMRSDJ 5,313,1985
Unscheduled DNA Synthesis	HeLa cell/human	50 µL/L	PMRSDJ 5,347,1985
Unscheduled DNA Synthesis	liver/rat	1 mmol/L	PMRSDJ 5,371,1985

Reproductive Effects Data and References

Route/Organism	Dose	Effect	Reference
skin/rat	9520 mg/kg (17W male)	Reproductive: Paternal effects: Spermatogenesis (including genetic material, sperm morphology, motility, and count) Reproductive: Effects on newborn: Physical	GTPZAB 27(9),47,1983
skin/rat	9520 mg/kg (17W prior to copulation)	Reproductive: Maternal effects: Menstrual cycle changes or disorders Reproductive: Effects on newborn: Growth statistics (e.g., reduced weight gain) Reproductive: Effects on newborn: Physical	GTPZAB 27(9),47,1983
skin/rat	952 mg/kg (17W prior to copulation)	Reproductive: Maternal effects: Ovaries, fallopian tubes Reproductive: Maternal effects: Menstrual cycle changes or disorders	GTPZAB 27(9),47,1983

Tumorigenic Data and References

Route/Organism	Dose	Effect	Reference
oral/rat	lowest published toxic dose: 109 gm/kg/2Y- continuous	Tumorigenic: Neoplastic by RTECS criteria Blood: Tumors	FCTOD7 25,619,1987
oral/rat	toxic dose: 7250 mg/kg/23W- continuous	Tumorigenic: Equivocal tumorigenic agent by RTECS criteria Kidney, Ureter, and Bladder: Bladder tumors	APMIAL 26,447,1949
subcutaneous/mouse	lowest published toxic dose: 320 mg/kg (15-21D pregnant)	Tumorigenic: Neoplastic by RTECS criteria Lung, Thorax, or Respiration: Tumors Reproductive: Tumorigenic effects: Transplacental tumorigenesis	BEXBAN 78,1402,1974
subcutaneous/rabbit	lowest published toxic dose: 840 mg/kg/14W- intermittent	Tumorigenic: Equivocal tumorigenic agent by RTECS criteria Kidney, Ureter, and Bladder: Bladder tumors	IMEMDT 27,155,1982

Acute Toxicity Data and References

Route/Organism	Dose	Effect	Reference
inhalation/man	lowest published toxic concentration: 25 mg/m³	Kidney, Ureter, and Bladder: Urine volume increased Kidney, Ureter, and Bladder: Hematuria Blood: Methemoglobinemia- Carboxhemoglobinemia	GTPZAB 14(8),7,1970
inhalation/rat	lethal concentration (50 percent kill): 862 ppm/4H	Behavioral: Somnolence (general depressed activity) Behavioral: Tremor Lung, Thorax, or Respiration: Cyanosis	NTIS** OTS0570956
intraperitoneal/mouse	lethal dose (50 percent kill): 113 mg/kg		HPV300 -,-,2001
oral/cat	lethal dose (50 percent kill): >50 mg/kg		HPV300 -,-,2001
oral/cat	lowest published lethal dose: 150 mg/kg	Behavioral: Coma Lung, Thorax, or Respiration: Dyspnea Blood: Methemoglobinemia- Carboxhemoglobinemia	XPHBAO 271,49,1941
oral/frog	lowest published lethal dose: 151 mg/kg	Behavioral: Coma Lung, Thorax, or Respiration: Dyspnea Blood: Methemoglobinemia- Carboxhemoglobinemia	XPHBAO 271,49,1941
oral/mammal (species unspecified)	lethal dose (50 percent kill): 1700 mg/kg		GTPZAB 32(10),25,1988
oral/mouse	lethal dose (50 percent kill): 520 mg/kg	Blood: Normocytic anemia Blood: Pigmented or nucleated red blood cells Blood: Methemoglobinemia- Carboxhemoglobinemia	IMEMDT 27,155,1982
oral/mouse	lethal dose (50 percent kill): 520 mg/kg		HPV300 -,-,2001
oral/rabbit	lethal dose (50 percent kill): 840 mg/kg		HPV300 -,-,2001
oral/rabbit	lethal dose (50 percent kill): 840 mg/kg	Blood: Normocytic anemia Blood: Pigmented or nucleated red blood cells Blood: Methemoglobinemia- Carboxhemoglobinemia	IMEMDT 27,155,1982
oral/rat	lethal dose (50 percent kill): 670 mg/kg	Blood: Normocytic anemia Blood: Pigmented or nucleated red blood cells Blood: Methemoglobinemia- Carboxhemoglobinemia	IMEMDT 27,155,1982
oral/rat	lowest published toxic dose: 60 mg/kg	Liver: Other changes Kidney, Ureter, and Bladder: Other changes Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Multiple enzyme effects	TXCYAC 186,67,2003
oral/rat	lethal dose (50 percent kill): 635 mg/kg		HPV300 -,-,2001
skin/rabbit	lethal dose (50 percent kill): 3250 µL/kg		AIHAAP 23,95,1962
skin/rabbit	lethal dose (50 percent kill): 3250 mg/kg		HPV300 -,-,2001
subcutaneous/rat	lethal dose (50 percent kill): 1115 mg/kg		HPV300 -,-,2001

Other Multiple Dose Data and References

Route/Organism	Dose	Effect	Reference
intraperitoneal/rat	lowest published toxic dose: 225 mg/kg/3D- intermittent	Liver: Other changes Kidney, Ureter, and Bladder: Other changes Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Multiple enzyme effects	HPV300 -,-,2001
oral/rat	lowest published toxic dose: 131040 mg/kg/104W- intermittent	Liver: Other changes Kidney, Ureter, and Bladder: Other changes Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Multiple enzyme effects	HPV300 -,-,2001
oral/rat	lowest published toxic dose: 1125 mg/kg/5D- continuous	Blood: Changes in spleen Nutritional and Gross Metabolic: Weight loss or decreased weight gain Related to Chronic Data: Death in the "MULTIPLE DOSE" data type field	FAATDF 3,285,1983
oral/rat	lowest published toxic dose: 10200 mg/kg/30D- intermittent	Kidney, Ureter, and Bladder: Proteinuria Blood: Normocytic anemia Nutritional and Gross Metabolic: Weight loss or decreased weight gain	VINIT* #4035-77
oral/rat	lowest published toxic dose: 1125 mg/kg/5D- intermittent	Blood: Methemoglobinemia- Carboxhemoglobinemia Blood: Changes in spleen	CICAD* VI:7,1,1998
oral/rat	lowest published toxic dose: 1148 mg/kg/4W- continuous	Liver: Other changes Blood: Changes in serum composition (e.g. TP, bilirubin, cholesterol) Nutritional and Gross Metabolic: Weight loss or decreased weight gain	IJTOFN 24,365,2005
oral/rat	lowest published toxic dose: 2086 mg/kg/2W- continuous	Nutritional and Gross Metabolic: Weight loss or decreased weight gain	IJTOFN 24,365,2005
oral/rat	lowest published toxic dose: 2190 mg/kg/30D- continuous	Blood: Methemoglobinemia- Carboxhemoglobinemia	IJTOFN 24,365,2005
oral/rat	lowest published toxic dose: 4004 mg/kg/91D- continuous	Blood: Methemoglobinemia- Carboxhemoglobinemia	IJTOFN 24,365,2005

Reviews

Organization	Standard	Reference
American Conference of Governmental Industrial Hygienists (ACGIH)	Threshold Limit Value-time-weighted average 2 ppm (skin)	DTLVS* TLV/BEI,2013
American Conference of Governmental Industrial Hygienists (ACGIH)	Threshold Limit Value-Confirmed animal carcinogen	DTLVS* TLV/BEI,2013
International Agency for Research on Cancer (IARC)	Cancer Review:Animal Sufficient Evidence	IMEMDT 99,451,2010
International Agency for Research on Cancer (IARC)	Cancer Review:Animal Sufficient Evidence	IMEMDT 100F,99,2012
International Agency for Research on Cancer (IARC)	Cancer Review:Animal Sufficient Evidence	IMEMDT 77,564,2000
International Agency for Research on Cancer (IARC)	Cancer Review:Human Limited Evidence	IMEMDT 77,564,2000
International Agency for Research on Cancer (IARC)	Cancer Review:Human Sufficient Evidence	IMEMDT 99,451,2010
International Agency for Research on Cancer (IARC)	Cancer Review:Human Sufficient Evidence	IMEMDT 100F,99,2012
International Agency for Research on Cancer (IARC)	Cancer Review:Group 2A	IMEMDT 77,564,2000
International Agency for Research on Cancer (IARC)	Cancer Review:Group 1	IMEMDT 100F,99,2012
International Agency for Research on Cancer (IARC)	Cancer Review:Group 1	IMEMDT 99,451,2010
TOXICOLOGY REVIEW		MUREAV 543,201,2003
TOXICOLOGY REVIEW		MUREAV 567,109,2004
TOXICOLOGY REVIEW		TCMUD8 23(Suppl 1),187,2003
TOXICOLOGY REVIEW		TXCYAC 196,1,2004
TOXICOLOGY REVIEW		MUREAV 588,88,2005
TOXICOLOGY REVIEW		FCTOD7 44,1699,2006
TOXICOLOGY REVIEW		MUREAV 627,10,2007
TOXICOLOGY REVIEW		ENTOX* -,104,2005
TOXICOLOGY REVIEW		MUREAV 627,59,2007
TOXICOLOGY REVIEW		ENTOX* -,206,2005
TOXICOLOGY REVIEW		BCLPT* 96,131,2005
TOXICOLOGY REVIEW		MUREAV 584,1,2005
TOXICOLOGY REVIEW		MUREAV 654,114,2008
TOXICOLOGY REVIEW		MUTAEX 23,153,2008
TOXICOLOGY REVIEW		MUREAV 751,49,2012
TOXICOLOGY REVIEW		MUREAV 752,99,2013
TOXICOLOGY REVIEW		MUREAV 769,34,2014
TOXICOLOGY REVIEW		MUREAV 768,27,2016
TOXICOLOGY REVIEW		MUREAV 802,1,2016
TOXICOLOGY REVIEW		MUTAEX 33,179,2018

Standards and Regulations

Organization	Standard	Reference
Mine Safety and Health Administration (MSHA) STANDARD-air	time-weighted average 5 ppm (22 mg/m³)	DTLVS* 3,261,1971
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 2 ppm (8.8 mg/m³), Carcinogen, JUL2008
Occupational Exposure Limit-AUSTRIA	TRK-TMW 0.1 ppm (0.5 mg/m³);KZW 0.4 ppm (2 mg/m³), skin, 2007
Occupational Exposure Limit-BELGIUM	time-weighted average 2 ppm (8.9 mg/m³), Skin, Carcinogen, MAR2002
Occupational Exposure Limit-DENMARK	time-weighted average 2 ppm (9 mg/m³), skin, carc, MAY2011
Occupational Exposure Limit-FINLAND	time-weighted average 2 ppm, short term exposure limit 4 ppm, skin, NOV2011
Occupational Exposure Limit-FRANCE	VME 2 ppm (9 mg/m³), C2 Carcinogen, FEB2006
Occupational Exposure Limit-HUNGARY	ceiling concentration 0.5 mg/m³, Skin, Carcinogen, SEP2000
Occupational Exposure Limit-ICELAND	time-weighted average 2 ppm (9 mg/m³), carc, skin, NOV2011
Occupational Exposure Limit-JAPAN	Occupational Exposure Limit 1 ppm (4.4 mg/m³), skin, 2A carc, MAY2012
Occupational Exposure Limit-KOREA	time-weighted average 2 ppm (9 mg/m³), carcinogen, skin, 2006
Occupational Exposure Limit-MEXICO	time-weighted average 5 ppm (22 mg/m³) (skin), 2004
Occupational Exposure Limit-NEW ZEALAND	time-weighted average 0.2 ppm (0.89 mg/m³), skin, JAN2002
Occupational Exposure Limit-NORWAY	time-weighted average 1 ppm (4.5 mg/m³), JAN1999
Occupational Exposure Limit-PERU	time-weighted average 2 ppm (8.8 mg/m³), JUL2005
Occupational Exposure Limit-POLAND	MAC(time-weighted average) 3 mg/m³, MAC(short term exposure limit) 9 mg/m³, JAN1999
Occupational Exposure Limit-RUSSIA	time-weighted average 0.5 mg/m³, short term exposure limit 1 mg/m³, Skin, JUN2003
Occupational Exposure Limit-SWITZERLAND	MAK-week 0.1 ppm (0.5 mg/m³), carc 2, skin, JAN2011
Occupational Exposure Limit-THE PHILIPPINES	time-weighted average 5 ppm (22 mg/m³), Skin, JAN1993
Occupational Exposure Limit-TURKEY	time-weighted average 5 ppm (22 mg/m³), Skin, JAN1993
Occupational Exposure Limit-UNITED KINGDOM	time-weighted average 0.2 ppm (0.89 mg/m³), skin, OCT2007
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Construction)	8H time-weighted average 5 ppm (22 mg/m³) (skin)	CFRGBR 29,1926.55,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Federal Contractors)	8H time-weighted average 5 ppm (22 mg/m³) (skin)	CFRGBR 41,50-204.50,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (General Industry)	8H time-weighted average 5 ppm (22 mg/m³) (skin)	CFRGBR 29,1910.1000,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Shipyards)	8H time-weighted average 5 ppm (22 mg/m³) (skin)	CFRGBR 29,1915.1000,1993

NIOSH Documentation and Surveillance

Organization	Standard	Reference
National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Level TO o-TOLUIDINE-air	Carcinogen lowest feasible concentration (Sk)	NIOSH* DHHS #92-100,1992
National Occupational Exposure Survey 1983	Hazard Code 73470; Number of Industries 32; Total Number of Facilities 2517; Number of Occupations 25; Total Number of Employees Exposed 30019; Total Number of Female Employees Exposed 15501
National Occupational Hazard Survey 1974	Hazard Code 73470; Number of Industries 21; Total Number of Facilities 2912; Number of Occupations 20; Total Number of Employees Exposed 13053

Status in Federal Agencies

Organization	Reference
EPA GENETOX PROGRAM 1988, Inconclusive: Histidine reversion-Ames test
EPA GENETOX PROGRAM 1988, Negative: Sperm morphology-mouse; S cerevisiae-homozygosis
EPA GENETOX PROGRAM 1988, Positive: Carcinogenicity-mouse/rat
EPA GENETOX PROGRAM 1988, Positive: Cell transform.-RLV F344 rat embryo
EPA GENETOX PROGRAM 1988, Positive: E coli polA without S9
EPA TSCA Section 8(b) CHEMICAL INVENTORY
EPA TSCA Section 8(d) unpublished health/safety studies
EPA TSCA TEST SUBMISSION (TSCATS) DATA BASE, JANUARY 2001
NIOSH Analytical Method, 1994: Amines, aromatic, 2002
NTP 14th Report on Carcinogens,2016:Known to be a human carcinogen
OSHA ANALYTICAL METHOD #ID-73

Page last reviewed: November 16, 2018

Content source: National Institute for Occupational Safety and Health