Identification of potential carcinogens in technical grade 1,1,1-trichloroethane.

Gas chromatography and gas chromatography-mass spectrometry were employed to analyze 22 samples of technical grade 1,1,1-trichloroethane for impurities. Eighteen contained vinylidene chloride (1,1-dichloroethylene) (30-900 micrograms/ml) and further contaminants were identified as 1,1-dichloroethane (11), trichloroethylene (12), and 1,1,2-trichloroethane (9). Nitromethane (18), 1,2-epoxybutane (19), tert. butanol (7), and dioxane (10) were detected as stabilizers. It is recommended that the manufacturers should eliminate vinylidene chloride and stabilizers which carry a carcinogenic and/or mutagenic risk, from technical samples of 1,1,1-trichloroethane.