Perchloroethylene

Perchloroethylene, also known as tetrachloroethene or perc, is a chlorinated hydrocarbon solvent widely used in dry cleaning and metal degreasing. It is produced industrially in large quantities from chlorinated hydrocarbons and is valued for its stability, solvent power, and relatively low odor. It is a colorless, dense liquid that is immiscible with water and has a boiling point of 121.4°C. It evaporates slowly and can persist in the environment when released.

In terms of health effects, inhalation or dermal exposure can affect the central nervous system, producing dizziness, fatigue, or confusion. Prolonged exposure has been linked to liver and kidney effects, and in risk assessments it is classified by IARC as a Group 2A carcinogen (probably carcinogenic to humans). Perc is persistent in soil and groundwater and can contaminate drinking-water sources; it volatilizes to air, contributing to urban and indoor air concentrations near facilities.

Regulation and environmental management: Many countries regulate occupational exposure to perchloroethylene and require engineering controls, ventilation, spill containment, and waste handling as hazardous material. In the dry-cleaning industry, efforts have shifted toward alternative solvents and closed systems to reduce emissions. Cleanup of spills and contaminated groundwater typically involves soil excavation, pump-and-treat, or advanced oxidation methods.

Safety and handling: Use only in well-ventilated areas with appropriate containment. Wear personal protective equipment, avoid skin and eye contact, and store in sealed containers away from heat or ignition sources. It is incompatible with some materials and oxidizers and should be disposed of as hazardous waste.