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!I t PROPERTIES OF MATERIALS AND TOXICOLOGICAL PROFILES Tetrachloroethylene Tetrachloroethylene (perchloroethylene) is a colorless, nonflammable liquid. It is moderately volatile and not very soluble in water (150 mg/1). Tetrachloroethylene resists hydrolysis and can be very stable in the environment..It can be biodegraded if the microorganisms are given time to adapt. Tetrachloroethylene is absorbed primarily by inhalation. Absorption is slow by ingestion and across the skin. Tetrachloroethylene is not highly metabolized. The half-life in the''body is about 65 hours for tetrachloroethylene and 144 hours for its metabolites. In high concentrations, tetrachloroethylene can act as an irritant of the eyes, nose and. throat. Prolonged dermal exposure can result in dermatitis. Tetrachloroethylene can act as a central nervous system depressant but primarily at high concentrations. Acute exposures can result in vertigo, fatigue, nausea and impaired coordination. Sustained atmospheric concentrations of 200 ppm can lead to narcosis and death. However, tetrachloroethylene has a low potential for producing organ damage in acute exposures. The LD 50s for oral administration were reported to be 8,850 mg/kg in rats and 8,100 mg/kg in mice. An LC50 for rats was reported as being 5,040 ppm for eight hours. The National Institute of Occupational Safety and Health time-weighted average has been set at 50 ppm (335 mg/cu m). Few problems from industrial exposures have been reported. Chronic exposure to tetrachloroethylene can result in liver and kidney damage. Tetrachloroethylene was found to cause liver tumors in mice but none in rats in National Cancer Institute bioassays. When administered to pregnant rats and mice, fetal weight was found to decrease and the number of resorptions increased, but no teratogenic effects were found. Mutagenicity studies with bacteria have given negative results. The EPA has set a suggested no-adverse-response level for tetrachloroethylene of 20 iug/I for long-term exposures. The EPA has set a recommended maximum contaminant level in drinking water of 0 ug/l. The EPA water quality criterion for tetrachloroethylene is 5,280 ug/I to protect freshwater aquatic life in acute exposures and 840 ug/I .in chronic exposures. E ,fpm Avalon Environmental Consultants 9627-001-6 Kashmar Singh Joes Truck Plaza ° January 9, 2001 Lathrop,California