A comparative study of the excretion of Fujiwara reaction-positive substances in urine of humans and rodents given trichloro-or tetrachloro-derivatives of ethane and ethylene.

Ikeda, M., and Ohtsuji, H. (1972). Brit. J. industr. Med., 29, 99-104. A comparative study on the excretion of Fujiwara reaction-positive substances in urine of humans and rodents given trichloroor tetrachloro-derivatives of ethane and ethylene. 1,1,1-Trichloroethane, 1,1,2trichloroethane, 1,1,1 ,2-tetrachloroethane, 1,1 ,2,2-tetrachloroethane, trichloroethylene, and tetrachloroethylene were administered to rats and mice as vapours at 200 p.p.m. for 8 hours and urine was collected for 48 hours. The urine was analysed by the Fujiwara reaction for total trichlorocompounds (TTC), trichloroacetic acid (TCA), and trichloroethanol (TCE). All compounds except 1,1,2-trichloroethane yielded substantial TCA and TCE but 1,1,1,2tetrachloroethane and trichloroethylene much more than the rest. The results obtained during two periods of 48 hours after intraperitoneal injection were similar. The variations in the amounts of metabolites are shown to be consistent with the vapour pressures of the solvents (compounds with high vapour pressures are lost from the lungs before being metabolized) and with their known chemical properties, according to which 1,1,1-trichlorocompounds should yield TCE and TCA readily, whereas 1,1,2-chlorocompounds should not. Excretion of metabolites from men exposed intermittently to vapours of tetrachloroethylene and trichloroethylene were also studied. Both gave enough TCE and TCA, but trichloroethylene gave considerably more, in accordance with its relative instability to oxidation.