Toluene, o-nitro-

RTECS #

XT3150000

CAS #

88-72-2; 57158-05-1
See: NMAM or OSHA Methods

Updated

March 2019

Molecular Weight

137.15

Molecular Formula

C₇H₇NO₂

Synonyms

1-Methyl-2-nitrobenzene
2-Methylnitrobenzene
2-Nitrotoluene
2-Nitrotoluol
Benzene, 1-methyl-2-nitro- (9CI)
Nitrotoluene, ortho-
o-Methylnitrobenzene
o-Nitrotoluene
o-Nitrotoluene (ACGIH:OSHA)
ONT
ortho-Nitrotoluol

Mutation Data and Reference

System Test	Route/Organism/Tissue	Dose	Reference
DNA adduct	oral/rat	150 mg/kg	CBINA8 51,131,1984
sister chromatid exchange	ovary/hamster	355 mg/L	EMMUEG 10(Suppl 10),1,1987
Unscheduled DNA Synthesis	oral/rat	200 mg/kg	CNREA8 43,2836,1983
Unscheduled DNA Synthesis	liver/rat	500 µg/L	EMMUEG 26,147,1995

Reproductive Effects Data and References

Route/Organism	Dose	Effect	Reference
oral/rat	32123 mg/kg (13W male)	Reproductive: Paternal effects: Spermatogenesis (including genetic material, sperm morphology, motility, and count) Reproductive: Paternal effects: Testes, epididymis, sperm duct	NTPTR* NIH-93-3346
oral/rat	69154 mg/kg (13W prior to copulation)	Reproductive: Maternal effects: Menstrual cycle changes or disorders	NTPTR* NIH-93-3346
oral/mouse	140 gm/kg (13W male)	Reproductive: Paternal effects: Spermatogenesis (including genetic material, sperm morphology, motility, and count)	NTPTR* NIH-93-3346

Tumorigenic Data and References

Route/Organism	Dose	Effect	Reference
oral/mouse	lowest published toxic dose: 109.5 gm/kg/2Y- continuous	Tumorigenic: Equivocal tumorigenic agent by RTECS criteria Vascular: Tumors Gastrointestinal: Colon tumors	TXCYAC 183,221,2003
oral/mouse	lowest published toxic dose: 219 gm/kg/2Y- continuous	Tumorigenic: Equivocal tumorigenic agent by RTECS criteria Gastrointestinal: Colon tumors Liver: Tumors	TXCYAC 183,221,2003
oral/rat	lowest published toxic dose: 32.12 gm/kg/13W- intermittent	Tumorigenic: Carcinogenic by RTECS criteria Reproductive: Other reproductive system tumors	TOXID9 72,143,2003
oral/rat	lowest published toxic dose: 26.57 gm/kg/13W- intermittent	Tumorigenic: Carcinogenic by RTECS criteria Liver: Tumors	TOXID9 72,143,2003
oral/rat	lowest published toxic dose: 54600 mg/kg/26W- continuous	Tumorigenic: Neoplastic by RTECS criteria Reproductive: Other reproductive system tumors	NTPTR* NIH-96-3936
oral/rat	lowest published toxic dose: 27.4 gm/kg/2Y- continuous	Tumorigenic: Equivocal tumorigenic agent by RTECS criteria Skin and Appendages: Tumors	TXCYAC 183,221,2003
oral/rat	lowest published toxic dose: 87.6 gm/kg/2Y- continuous	Tumorigenic: Equivocal tumorigenic agent by RTECS criteria Liver: Tumors Skin and Appendages: Tumors	TXCYAC 183,221,2003
oral/rat	lowest published toxic dose: 10.1 gm/kg/12W- continuous	Tumorigenic: Equivocal tumorigenic agent by RTECS criteria Liver: Tumors Skin and Appendages: Tumors	TXCYAC 183,221,2003
oral/rat	lowest published toxic dose: 25.2 gm/kg/12W- continuous	Tumorigenic: Equivocal tumorigenic agent by RTECS criteria Lung, Thorax, or Respiration: Tumors Liver: Tumors	TXCYAC 183,221,2003
oral/rat	lowest published toxic dose: 45.6 gm/kg/2Y- continuous	Tumorigenic: Equivocal tumorigenic agent by RTECS criteria Skin and Appendages: Tumors	TXCYAC 183,221,2003
oral/rat	lowest published toxic dose: 182.5 gm/kg/2Y- continuous	Tumorigenic: Equivocal tumorigenic agent by RTECS criteria Liver: Tumors Skin and Appendages: Tumors	TXCYAC 183,221,2003

Acute Toxicity Data and References

Route/Organism	Dose	Effect	Reference
inhalation/mouse	lethal concentration (50 percent kill): 328 mg/m³	Brain and Coverings: Recordings from specific areas of CNS Liver: Fatty liver degeneration Blood: Methemoglobinemia- Carboxhemoglobinemia	GTPZAB 22(7),52,1978
inhalation/rat	lethal concentration (50 percent kill): 790 mg/m³	Brain and Coverings: Recordings from specific areas of CNS Liver: Fatty liver degeneration Blood: Methemoglobinemia- Carboxhemoglobinemia	GTPZAB 22(7),52,1978
oral/mouse	lethal dose (50 percent kill): 970 mg/kg		GTPZAB 25(8),50,1981
oral/rabbit	lethal dose (50 percent kill): 1750 mg/kg	Brain and Coverings: Recordings from specific areas of CNS Liver: Fatty liver degeneration Blood: Methemoglobinemia- Carboxhemoglobinemia	GTPZAB 22(7),52,1978
oral/rat	lethal dose (50 percent kill): 891 mg/kg		HPV005 -,-,2006

Other Multiple Dose Data and References

Route/Organism	Dose	Effect	Reference
oral/mouse	lowest published toxic dose: 70343 mg/kg/13W- continuous	Olfaction: Change in olfactory nerve Liver: Changes in liver weight Kidney, Ureter, and Bladder: Changes in bladder weight	NTPTR* NIH-93-3346
oral/mouse	lowest published toxic dose: 8400 mg/kg/14D- intermittent	Blood: Changes in other cell count (unspecified)	DCTODJ 17,359,1994
oral/mouse	lowest published toxic dose: 6825 mg/kg/13W- continuous	Nutritional and Gross Metabolic: Weight loss or decreased weight gain	TXCYAC 183,221,2003
oral/mouse	lowest published toxic dose: 33600 mg/kg/8W- continuous	Nutritional and Gross Metabolic: Weight loss or decreased weight gain	TXCYAC 183,221,2003
oral/mouse	lowest published toxic dose: 109500 mg/kg/2Y- continuous	Gastrointestinal: Other changes Gastrointestinal: Tumors	CRNGDP 25,605,2004
oral/mouse	lowest published toxic dose: 840 mg/kg/2W- continuous	Liver: Other changes	CRNGDP 26,689,2005
oral/rat	lowest published toxic dose: 32123 mg/kg/13W- continuous	Liver: Changes in liver weight Blood: Changes in platelet count Related to Chronic Data: Changes in testicular weight	NTPTR* NIH-93-3346
oral/rat	lowest published toxic dose: 54600 mg/kg/26W- continuous	Liver: Changes in liver weight Nutritional and Gross Metabolic: Weight loss or decreased weight gain Related to Chronic Data: Changes in testicular weight	NTPTR* NIH-96-3936
oral/rat	lowest published toxic dose: 3937.5 mg/kg/15W- continuous	Nutritional and Gross Metabolic: Weight loss or decreased weight gain	TXCYAC 183,221,2003
oral/rat	lowest published toxic dose: 21000 mg/kg/30W- continuous	Nutritional and Gross Metabolic: Weight loss or decreased weight gain	TXCYAC 183,221,2003
oral/rat	lowest published toxic dose: 36.4 gm/kg/26W- intermittent	Blood: Changes in spleen	TOXID9 72,143,2003
oral/rat	lowest published toxic dose: 924 mg/kg/3W- intermittent	Blood: Methemoglobinemia- Carboxhemoglobinemia	TOXID9 72,143,2003

Reviews

Organization	Standard	Reference
American Conference of Governmental Industrial Hygienists (ACGIH)	Threshold Limit Value-time-weighted average 2 ppm (skin)	DTLVS* TLV/BEI,2013
International Agency for Research on Cancer (IARC)	Cancer Review:Animal Limited Evidence	IMEMDT 65,409,1996
International Agency for Research on Cancer (IARC)	Cancer Review:Animal Sufficient Evidence	IMEMDT 101,112,2013
International Agency for Research on Cancer (IARC)	Cancer Review:Human Inadequate Evidence	IMEMDT 65,409,1996
International Agency for Research on Cancer (IARC)	Cancer Review:Human Inadequate Evidence	IMEMDT 101,111,2013
International Agency for Research on Cancer (IARC)	Cancer Review:Group 3	IMEMDT 65,409,1996
International Agency for Research on Cancer (IARC)	Cancer Review:Group 2A	IMEMDT 101,112,2013
TOXICOLOGY REVIEW		MUREAV 588,88,2005
TOXICOLOGY REVIEW		BCLPT* 96,131,2005
TOXICOLOGY REVIEW		HETOEA 25,413,2006
TOXICOLOGY REVIEW		MUREAV 659,248,2008
TOXICOLOGY REVIEW		MUTAEX 23,271,2008
TOXICOLOGY REVIEW		MUREAV 721,27,2011
TOXICOLOGY REVIEW		MUREAV 751,49,2012
TOXICOLOGY REVIEW		RTOPDW 53,134,2009
TOXICOLOGY REVIEW		RTOPDW 60,120,2011

Standards and Regulations

Organization	Standard	Reference
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 (11 mg/m³), JUL2008
Occupational Exposure Limit-AUSTRIA	TRK-TMW 0.5 mg/m³;KZW 2 mg/m³, skin, 2007
Occupational Exposure Limit-BELGIUM	time-weighted average 2 ppm (11 mg/m³), Skin, MAR2002
Occupational Exposure Limit-DENMARK	time-weighted average 2 ppm (12 mg/m³), skin, MAY2011
Occupational Exposure Limit-ICELAND	time-weighted average 2 ppm (12 mg/m³), skin, NOV2011
Occupational Exposure Limit-KOREA	time-weighted average 2 ppm (11 mg/m³), skin, 2006
Occupational Exposure Limit-MEXICO	time-weighted average 5 ppm (30 mg/m³);short term exposure limit 10 ppm (60 mg/m³), 2004
Occupational Exposure Limit-NEW ZEALAND	time-weighted average 2 ppm (11 mg/m³), skin, JAN2002
Occupational Exposure Limit-NORWAY	time-weighted average 1 ppm (5.5 mg/m³), JAN1999
Occupational Exposure Limit-PERU	time-weighted average 2 ppm (11 mg/m³), JUL2005
Occupational Exposure Limit-SWEDEN	time-weighted average 1 ppm (6 mg/m³);short term exposure limit 2 ppm (11 mg/m³), Skin, JUN2005
Occupational Exposure Limit-SWITZERLAND	carc 2, JAN2011
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Construction)	8H time-weighted average 5 ppm (30 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 (30 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 (30 mg/m³) (skin)	CFRGBR 29,1910.1000,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Shipyards)	8H time-weighted average 5 ppm (30 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-NITROTOLUENE-air	10H time-weighted average 2 ppm (Sk)	NIOSH* DHHS #92-100,1992
National Occupational Hazard Survey 1974	Hazard Code 81910; Number of Industries 2; Total Number of Facilities 20; Number of Occupations 2; Total Number of Employees Exposed 285

Status in Federal Agencies

Organization	Reference
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
NCI Carcinogenesis Studies (feed);clear evidence:mouse,rat
NTP 14th Report on Carcinogens,2016:Reasonably anticipated to be human carcinogen
NTP Carcinogenesis studies; on test (two year studies), October 2000
NTP Toxicity studies, RPT# TOX-23, October 2000
NTP Toxicity studies, RPT# TOX-44, October 2000

Page last reviewed: November 16, 2018

Content source: National Institute for Occupational Safety and Health