Human exposure, perchloroethylene

Our assignment for EPA was to apply quantitative risk analysis methods to the determination of risk for a particular chemical. The health risks for perchloroethylene turned out to be highly uncertain, but by using decision analysis concepts we were able to display this uncertainty in terms of alternative assumptions about the dose response relationship. Similar methods might be used to characterize uncertainties about human exposure to a chemical agent or about the costs to producers and consumers of a restriction on chemical use. 

Hepatic Effects. Data in humans are limited to one study which reported significant dose-related increases in the concentration of serum bile acids in workers after inhalation exposure to hexachlorobutadiene (0.005-0.02 ppm) (Driscoll et al. 1992). The practical importance of this finding is reduced because workers were also potentially exposed to other solvents (carbon tetrachloride and perchloroethylene) and background information on other confounding variables was minimal. No studies were located regarding other hepatic effects in humans. 

Despite the widespread use, there are many health, safety, and environmental concerns associated with the use of perc. Perchloroethylene has been described as a probable human carcinogen based on both laboratory animal studies and human epidemiological studies (IARC, 1995). According to the USEPA (1998), there is a reasonable basis to conclude that there can be a health risk for cancer and some non-cancer effects to workers from the relatively high PCE exposures observed on the average in the dry cleaning industry. Risks also exist for apartment residents colocated with a perc dry cleaning facility. 

Eamest GS, Spencer AB. 1995. In-depth survey report Perchloroethylene exposures in commercial dry cleaners at Brown s Cleaners, Santa Monica, California. U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health. Report No. ECTB 201-16a. 47 pages. 

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