Chloroform affects the central nervous system, liver, and kidneys. It was used as a surgical anaesthetic for many years before its harmful effects on the liver and kidneys were recognized. Short-term exposure to high concentrations of chloroform in the air causes tiredness, dizziness, and headache. Longer-term exposure to high levels of chloroform in the air, or in food and drinking water, can affect liver and kidney function. Toxic effects may include jaundice and burning urination. It is rapidly eliminated from the body. The US Department of Health and Human Services has determined that chloroform may reasonably be anticipated to be a carcinogen.
Chloroform can enter the body by breathing air, eating food, or drinking water that contains chloroform. Chloroform readily penetrates the skin and may enter the body by bathing or showering in water containing chloroform. Foods such as seafood, dairy products, meat, vegetables, bread, and beverages may contain small but measurable amounts of chloroform. Drinking-water supplies containing organic contaminants may contain chloroform as a by-product of chlorination of the water supply for disinfection purposes.
Chloroform is found in a wide variety of occupational settings as a result of its direct use in manufacturing processes, its use as a solvent for many different materials, and its formation during various chlorination processes. Occupational settings in which chloroform exposure may occur include: Chloroform manufacturing plants; Fluorocarbon-22 manufacturing plants; Ethylene dichloride manufacturing plants; Internal combustion engine industries; Pesticide manufacturing plants; Pulp and paper mills; Food processing industries; Paint stores (as a result of using chloroform-containing solvents for lacquers, gums, greases, waxes, adhesives, oils, and rubber).
The general population may be exposed to chloroform by breathing air and ingesting drinking water, beverages, and foods contaminated with chloroform. In addition, skin contact may occur during the use of various consumer products containing this compound or from exposure to chlorinated waters, such as swimming pool water. According to the USA EPA, more than four-fifths of the excess environmental risk of cancer in Philadelphia comes from drinking water contaminated chiefly by chloroform.
The risks of cancer, if any, from low-level exposures to chloroform in drinking water as a result of chlorination, however, are far outweighed by the benefits of chlorination in terms of greatly decreased incidence of waterborne diseases, themselves a potential public health threat and a previous major contributor to sickness and death.