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CAS No. 95-53-4
ortho-Toluidine (CH3C6H4NH2) is a colorless to pale-yellow liquid. It is a toxic substance harmful to the eyes, skin, and when swallowed or inhaled. ortho-Toluidine can cause cancer. Workers may be harmed from exposure to ortho-toluidine. The level of exposure depends upon the dose, duration, and work being done.
ortho-Toluidine is used in many industries. It is used in some hair dyes, weed and pest killers, rubber, and in some laboratory processes. Some examples of workers at risk of being exposed to ortho-toluidine include the following:
- Workers who are exposed to certain hair dyes
- Factory workers involved in rubber manufacture
- Employees who are exposed to cigarette smoke
- Laboratory workers who stain tissues or analyze glucose
NIOSH recommends that employers use Hierarchy of Controls to prevent injuries. If you work in an industry that uses ortho-toluidine, please read chemical labels and the accompanying Safety Data Sheets for hazard information. Visit NIOSH’s page on Managing Chemical Safety in the Workplace to learn more about controlling chemical workplace exposures.
The following resources provide information about occupational exposure to ortho-toluidine. Useful search terms for ortho-toluidine include “2-aminotoluene,” “o-aminotoluene,” “1-methyl-2-aminobenzene,” “2-methylaniline,” “o-methylaniline,” “o-toluidine,” and “o-tolylamine.”
If you work with this chemical, it is important to limit your exposure as much as possible.
Learn more about o-toluidine and how to keep workers safe.
Learn how o-toluidine looks and smells, How exposure occurs, Who is most likely to be exposed, Health problems it can cause
Learn what you can do to keep yourself and your family safe, Read worker health study summaries related to o-toluidine
The NIOSH Pocket Guide to Chemical Hazards (NPG) helps workers, employers, and occupational health professionals recognize and control workplace chemical hazards.
The NIOSH Manual of Analytical Methods (NMAM) is a collection of methods for sampling and analysis of contaminants in workplace air, and in the blood and urine of workers who are occupationally exposed.
The Health Hazard Evaluation Program (HHE) conducts onsite investigations of possible worker exposure to chemicals. Search the HHE database for more information on ortho-toluidine.
- NIOSHTIC-2 search results on ortho-toluidine—NIOSHTIC-2 is a searchable database of worker safety and health publications, documents, grant reports, and journal articles supported in whole or in part by NIOSH.
- Immediately Dangerous to Life or Health (IDLH) Value Profile: Toluidine—NIOSH reviews relevant scientific data and researches methods for developing IDLH values.
- NIOSH Worker Health Study Summaries: o-Toluidine Exposure—NIOSH conducts research to prevent illnesses and injuries in the workplace. The NIOSH Worker Notification Program notifies workers and other stakeholders about the findings of these research studies.
- Preventing Bladder Cancer from Exposure to o-Toluidine and Aniline—DHHS (NIOSH) Publication No. 90-116. This report increases awareness and recommends work practices to reduce exposures.
- NIOSH Cancer, Reproductive Health, and Cardiovascular Disease Program—DHHS (NIOSH) Publication No. 2016-137. The NIOSH Cancer, Reproductive Health, and Cardiovascular Disease (CRC) Program works with partners in industry, labor, trade associations, professional organizations, and academia.
- Morton International Chemical Company, Paterson, New Jersey—Health Hazard Evaluation (HHE) Report 90-0391-2346
- NIOSH Alert: Request for Assistance in Preventing Bladder Cancer from Exposure to o-Toluidine and Aniline—MMWR, May 31, Vol. 40, No. 21
- Amine, Aromatic Method 2002—Sampling and measurement, NMAM, fourth edition
- Aniline, o-Toluidine, and Nitrobenzene Method 2017—Sampling and measurement, NMAM, fourth edition
- Aniline and o-Toluidine in Urine Method 8317—Sampling and measurement, NMAM, fourth edition
- A Study of Causes of Death at a Rubber and Plastics Chemical Manufacturing Company
- Assessment of Exposure to o-Toluidine and Other Aromatic Amines in a Rubber Chemical Manufacturing Plant
- EPA Chemistry Dashboard: 2-MethylanilineExternal
- EPA Hazardous Air Pollutants’ Fact Sheet Chemical Cross ReferenceExternal
- IARC Monographs (Vol. 100F): ortho-ToluidineExternal
- IARC Monographs (Vol. 99): ortho-ToluidineExternal
- NLM TOXNET: 2-AminotolueneExternal
- NLM Haz-Map: o-ToluidineExternal
- NTP Report on Carcinogens (Fourteenth Edition): o-ToluidineExternal
- NTP Report on Carcinogens: Monograph on ortho-ToluidineExternal
- NTP Scientific Review of o-ToluidineExternal
- OSHA Hazard CommunicationExternal
- OSHA Sampling and Analytical Methods: o-, m-, p-ToluidineExternal
- New Jersey Hazardous Substance Fact Sheet: o-ToluidineExternal
- American Cancer Society: Known and Possible Human CarcinogensExternal
- Canadian Centre for Occupational Health and Safety (CCOHS) Fact Sheet: ortho-ToluidineExternal
- European Chemicals Agency (ECHA): o-ToluidineExternal
- Gestis Substance DatabaseExternal
- International Chemical Safety Cards: ortho-ToluidineExternal
- IPCS INCHEM CICAD No. 7: ortho-ToluidineExternal
- IPCS INCHEM Summaries & Evaluations: ortho-ToluidineExternal
- OECD Global Portal to Information on Chemical SubstancesExternal
- OECD SIDS Initial Assessment Report: ortho-ToluidineExternal