ORTHO-TOLUIDINE
NOTE: This page is archived for historical purposes and is no longer being maintained or updated.
About o-Toluidine
Below is some information about o-toluidine and the health problems it may cause. This information may be helpful to determine whether you are or have been exposed to o-toluidine in your job or whether symptoms you’ve experienced could be related to o-toluidine exposure.
What it looks like
- At room temperature, it is a thick, light yellow liquid
- When exposed to air and light, it will darken to reddish/orange brown
What it smells like
- It has a fishy odor
- It has a low odor threshold, which means most people will smell it even at very low levels.
How you can be exposed
- Breathing it in
- Getting it on your skin
Who is most likely exposed
- Industrial workers who use it
Beyond the industrial setting, there is little information available about o-toluidine exposure among other workers and the general public. We know that others may also be exposed, but probably at lower levels, including:
- Hair stylists because o-toluidine is used in some hair dyes.
- Laboratory workers who use o-toluidine to stain tissues or as part of a reagent to analyze glucose.
- The general public because o-toluidine is in
- cigarette smoke
- certain hair dyes
- Prilocaine, a cream that is applied to the skin to numb it for minor dental and surgical procedures and blood draws. Our bodies convert Prilocaine to o-toluidine after it is absorbed.
- air, soil, or water contaminated with o-toluidine
Health problems it may cause
Short-term effects
- skin, eye, and respiratory irritation
- cyanosis from a decrease in the supply of oxygen to the body due to methemoglobinemia. This condition occurs when o-toluidine changes hemoglobin, which carries oxygen in the blood, to methemoglobin, which hinders the release of oxygen.
- central nervous system depression including dizziness, headache, and confusion
Long-term effects
- bladder cancer
- anemia
- decreased appetite and weight loss
- cyanosis and methemoglobinemia
- skin lesions
- central nervous system depression including dizziness, headache, and confusion
If you are an industrial worker who works with o-toluidine, learn how to keep yourself and your family safe.
- Page last reviewed: June 6, 2014 (archived document)
- Content source:
- National Institute for Occupational Safety and Health Division of Surveillance, Hazard Evaluations and Field Studies