Evidence of hepatic conversion of C6 and C8 chlorotrifluoroethylene (CTFE) oligomers to their corresponding CTFE acids.

The toxicity of polychlorotrifluoroethylene oil (3.1 oil) hydraulic fluid is believed to be related to the conversion of neutral chlorotrifluoroethylene (CTFE) oligomers to their corresponding halogenated fatty acids. Male Fischer-344 rats were orally gavaged (1.25 g/kg/d) with two batch formulated 3.1 oils (3.1 oil-C6 and 3.1 oil-C6:C8) and C6 CTFE (trimer) and C8 CTFE (tetramer) oligomers, respectively. All rats exposed to test compounds for 7 days demonstrated significant 2-fold increases in liver weight over controls. After 24-h and 7-day dosings, the amount of tetramer acid formed in the liver was 2x and 11x the amount of trimer acid formed, respectively. In addition to the formation of tetramer acid, rats dosed with tetramer also indicated comparable amounts of trimer acid. These data indicate that toxicity induced by the 3.1 oil may be due to the retention of the tetramer and the resulting persistent high concentrations of halogenated fatty acids.