Cancer, perchloroethylene exposure

Is the risk of cancer posed by perchloroethylene "unreasonable" under the language of TSCA No clear answer emerges from the illustrative analysis. Whether a risk is unreasonable is not a matter to be determined from scientific evidence on toxicity and exposure, but rather a determination that will hinge on judgment. We concluded from our calculations that the uncertainty in projected annual cancer incidence from PCE was nearly five orders of magnitude, and such large uncertanties in health impacts may be typical for many chemical agents. 

Chronic-Duration Exposure and Cancer. Data in humans are limited to one study that reported increases in serum bile acids in workers chronically exposed to vapors of hexachlorobutadiene (0.005-0.02 ppm). Because workers were also potentially exposed to other chemicals (carbon tetrachloride and perchloroethylene), these effects cannot be attributed to hexachlorobutadiene exposure alone. No studies are available on the effects of hexachlorobutadiene in humans after oral or dermal exposure. 

Mundt KA, BirkT, Burch MT Critical review of the epidemiological literature on occupational exposure to perchloroethylene and cancer. Int Arch Occup Environ Health 2003 76 473. [PMID 12898270]... 

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. 

WeissNS. 1995. Cancer in relation to occupational exposure to perchloroethylene. Cancer Causes Control 6 257-266. 

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