Depuration rates of chlordane compounds from rat fat

Abstract

m 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, y-and a-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 111). 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.

Maternal Transfer of Chlordane and Its Metabolites to the Eggs of a Stream Mayfly Centroptilum triangulifer

“…Metabolically, this is consistent with the relative ease of enzymatic oxidation of the heptachloro and octachloro components over the nonachloro compounds (23)(24)(25). The greater number of chlorines apparently blocks access to the carbon bonds for oxidation (see Chart 1) (26). The half-life of nonachlor, which is indicative of susceptibility to metabolism and excretion, was determined to be approximately three times that of the octachloro compounds in rats (26).…”

“…The greater number of chlorines apparently blocks access to the carbon bonds for oxidation (see Chart 1) (26). The half-life of nonachlor, which is indicative of susceptibility to metabolism and excretion, was determined to be approximately three times that of the octachloro compounds in rats (26).…”

A Multi-elemental Approach to Identification of Subpopulations of North Atlantic Minke Whales Balaenoptera Acutorostrata

“…Among 102 PCB congeners and several other OCs in the blubber of the same minke whales (Hobbs et al 2003), the following eight were selected for the analysis: PCB153, PCB138 and PCB180, p,p′‐DDE, HCB, trans‐nonachlor, mirex and dieldrin. These OCs are known to have long half‐lives in mammals (Matthews & Dedrick 1984, Dearth & Hites 1991).…”

“…These OCs are known to have long half-lives in mammals (Matthews & Dedrick 1984, Dearth & Hites 1991.…”

Chlordane as undesirable substance in animal feed - Scientific Opinion of the Panel on Contaminants in the Food Chain

“…This configuration is the same as for trans-nonachlor and MC5, which both accumulate more in human tissues than cis-nonachlor, and MC7, which have chlorine in exo-configuration at C2 (Dearth and Hites, 1991b; Zhu et al, 1995). This is further evidenced by the fact that transnonachlor and U82 both have similar half-lives, 15 and 16 days, respectively, in rats, only exceeded by U81 (octachlordane, structure not known) and MC6 (nonachlordane) (>30 days) (Dearth and Hites, 1991c).…”