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CAS No. 67-66-3

Chloroform (CHCl3) is a colorless liquid that quickly evaporates into gas. It can harm the eyes, skin, liver, kidneys, and nervous system. Chloroform can be toxic if inhaled or swallowed. Exposure to chloroform may also cause cancer. Workers may be harmed from exposure to chloroform. The level of exposure depends upon the dose, duration, and work being done.

Chloroform is used in many industries. It is released from pulp and paper mills, hazardous waste sites, chlorinated water, and certain landfills. Chloroform is used in some refrigerants, solvents, and chemical manufacturing. Some examples of workers at risk of being exposed to chloroform include the following:

  • Workers involved in paper manufacture or recycle industries
  • Service employees exposed to some air conditioner refrigerants
  • Equipment operators working at sanitary landfills
  • Workers who work in water treatment plants

NIOSH recommends that employers use Hierarchy of Controls to prevent injuries. If you work in an industry that uses chloroform, 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 chloroform. Useful search terms for chloroform include “methane trichloride” and “trichloromethane.”

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