Environmental occurrence, analysis, and toxicology of toxaphene compounds

Toxaphene production, in quantities similar to those of polychlorinated bip henyls, has resulted in high toxaphene levels in fish from the Great lakes and in Arctic marine mammals (up to 10 and 16 mu g g(-1) lipid). Because of the large variability in total toxaphene data, few reliable conclusions ca n be drawn about trends or geographic differences in toxaphene concentratio ns. New developments in mass spectrometric detection using either negative chemical ionization or electron impact modes as well as in multidimensional gas chromatography recently have led researchers to suggest congener-speci fic approaches. Recently, several nomenclature systems have been developed for toxaphene compounds. Although all systems have specific advantages and limitations, it is suggested that an international body such as the interna tional Union of Pure and Applied Chemistry make an attempt to obtain unifor mity in the literature. Toxicologic information on individual chlorobornane s is scarce, bur some reports have recently appeared. Neurotoxic effects of toxaphene exposure such as those on behavior and learning have been report ed. Technical toxaphene and some individual congeners were found to be weak ly estrogenic in in vitro test systems; no evidence for endocrine effects i n vivo has been reported. in vitro studies show technical toxaphene and tox aphene congeners to be mutagenic. However, in vivo studies have not shown g enotoxicity; therefore, a nongenotoxic mechanism is proposed. Nevertheless, toxaphene is believed to present a potential carcinogenic risk to humans. Until now, only Germany has established a legal tolerance level for toxaphe ne-0.1 mg kg(-1) wet weight for fish.