TRICHLOROETHYLENE:A CURRENT REVIEW OF METABOLISM, MODE OF ACTION, AND REGULATORY CONSIDERATIONS

Trichloroethylene (TRI) is a volatile, mobile, clear, colorless liquid that has been widely used in industry as a solvent and cleaner and has become a major groundwater contaminant. TRI is a well-recognized animal carcinogen, exhibiting marked sex- and species-dependent differences in susceptibility and target organ specificity. Controversy exists, however, about the cancer risk to humans from TRI exposure. Bioassays in laboratory animals have demonstrated increased incidences of liver and lung tumors in mice, and low, not always consistent, incidences of kidney tumors in male rats. In humans, however, direct evidence of carcinogenicity from TRI exposure is equivocal, although a few epidemiological studies have linked TRI exposure with increased incidence of urinary-tract tumors and lymphomas in workers and with childhood leukemia. Some studies have found evidence of renal injury and increased incidence of renal tumors, although many of these studies have small cohorts, incomplete exposure information, an...