DEPURATION RATES OF CHLORDANE COMPOUNDS FROM RAT FAT

Rats were fed a diet containing 10 ppm of technical chlordane for 28 days. The depuration of the various chlordane compounds was then followed for 32 days. The concentrations of 14 components or metabolites of technical chlordane were measured in the adipose tissues of 21 rats, using electron capture, negative ionization mass spectrometry, coupled with capillary gas chromatography. The half-lives of the two major octachloro isomers, gamma- and alpha-chlordane, were determined to be 7.1 and 5.9 days, respectively. The half-lives of the nonachlors were 9.7 (cis-nonachlor), 14.3 (trans-nonachlor), and 54.1 days (nonachlor III). The depuration rates seem to be controlled by three structural features of the molecules: the total number and configuration of the chlorines on ring 1 and the number of chlorines on carbon 2.