Enantioselective degradation of α-hexachlorocyclohexane and cyclodiene insecticides in roe-deer liver samples from different regions of Germany

Remarkably high concentrations of α-hexachlorocyclohexane (α-HCH), cis-heptachlorepoxide and oxychlordane were found in roe-deer liver samples both from the northern and southern German states Schleswig-Holstein and Baden-Württemberg, respectively. The data revealed no significant regional differences, but they showed some common characteristics: a preferential degradation of (+)-α-HCH, and a preferential enrichment of (+)-oxychlordane and of (+)- cis-heptachlorepoxide as determined by chiral capillary gas chromatography using modified cyclodextrin phases. Calculation of the spearman rank correlation coefficients r s supported the assumption that higher concentrations of α-HCH may result in a stronger decomposition of the (+)-enantiomer, while higher levels of cis-heptachlorepoxide and oxychlordane appear to lead to a faster decomposition of the respective (-)-enantiomer or a preferential formation of the respective (+)-enantiomer.