Trichloroethylene

Trichloroethylene is a chemical compound with the formula C₂HCl₃. It is known as TCE for short. TCE is a pleasant-smelling colourless liquid. TCE is used as a solvent to dissolve oils. It was previously used in anaesthesia after chloroform, TCE for use in anaesthesia was dyed blue so it would not be confused with chloroform which smells, weighs and looks the same. It was sold under the name Trilene and Trimar. It should not be confused with the similar 1,1,1-trichloroethane, which was commonly known as chlorothene and also used as an industrial solvent.

Bottle of trichloroethylene for anaesthesia, from the United Kingdom

TCE was a very common dry cleaning solvent but it was way too strong and caused damage to clothes. Dry cleaners today use the safer perchloroethylene (PCE). TCE is still sometimes used as a stain remover.

TCE is used as a solvent to clean oils from metals but it can break down in presence of metals so producers add various chemicals into commercial TCE to prevent any unwanted reactions.

Hazards

Breathing TCE vapours can cause unconsciousness. It should be used in well-ventilated places. Its effects are similar to being drunk with alcohol. TCE has low toxicity in short-term. It is metabolised to chloral hydrate. It can harm the liver in long time. TCE is a weak carcinogen.^[1]

TCE is unstable under light and bases can break it down to HCl and dichloroacetylene, a neurotoxin.