tetrachloroethylene

Tetrachloroethylene, also known as perchloroethylene or perc, is a chlorinated hydrocarbon solvent used widely in industry. It is a colorless liquid at room temperature with a characteristic, mild odor. It is nonflammable, has a boiling point around 121°C, and is denser than water, with vapor that is heavier than air. It is only sparingly soluble in water and is relatively immiscible with many organic solvents.

The principal use of tetrachloroethylene is as a dry cleaning solvent for textiles. It is also employed as a degreasing agent for metal parts and in various industrial cleaning applications. In addition, it has been used in some chemical synthesis and extraction processes.

Environmentally, tetrachloroethylene is comparatively persistent. It readily volatilizes from surface water and soil, but can contaminate soils and groundwater through leaks, spills, or improper disposal, particularly near dry-cleaning facilities. Remediation typically involves soil vapor extraction, air stripping, or in-situ or ex-situ groundwater treatment.

Health effects are a major concern with tetrachloroethylene. Acute exposure can cause dizziness, headaches, confusion, and impaired coordination. Prolonged or high-level exposure can affect the liver and kidneys and may impact the nervous system. IARC classifies tetrachloroethylene as probably carcinogenic to humans, reflecting evidence of cancer risk from occupational exposure.

Safety and regulation emphasize controlling worker exposure and emissions. Use requires adequate ventilation, engineering controls, and personal protective equipment. Many jurisdictions regulate occupational exposures and environmental releases due to health and environmental concerns.

See also: dry cleaning, chlorinated solvents, IARC classification.