Gas chromatographic separation of toxaphene residues by DB-XLB (original) (raw)

Residues of toxaphene, a persistent organochlorine biocide, are difficult to characterize in the environment due to their complex composition, selective recalcitrance, and lack of a comprehensive standards set. No single gas chromatographic column stationary phase completely separates toxaphene on a congener specific basis. Using GC-ECD and GC-MS, the performance of a slightly polar stationary phase (DB-XLB) was compared with that of a widely used nonpolar phase (DB-5). Commercially available standard mixtures and tissue samples from a toxaphene-contaminated coastal marsh were analyzed. Both DB-5 and DB-XLB fully resolved a similar number of target congeners (18 of 22). The XLB phase, however, better resolved congener pairs P31/32, P40/ 41, and several others (e.g. P26/-1, Hx-Sed, and Hp-Sed). Compared with DB-5 and several recently evaluated, slightly polar phases, DB-XLB offers excellent overall performance for single column analysis of environmentally relevant toxaphene residues.