Toxaphene: a challenging analytical problem

Abstract

The analysis of toxaphene, a highly complex mixture of chlorinated bornanes, bornenes and camphenes, is a challenging problem, especially as individual congeners are present at trace levels in biota and other relevant samples. The complicated nomenclature of the compounds of interest is briefly discussed. Gas chromatographic techniques are the most important tools in toxaphene analysis because of their high resolution. The main focus of attention is devoted to important steps in the GC-based analytical procedure, such as sample preparation and injection, separation by single-column and multidimensional GC, both heart-cut and comprehensive, and detection by electron capture and, increasingly, MS-based detection/identification. The gradual shift from total toxaphene to individual compound analysis is discussed, and the growing interest in enantiomer-selective separations is highlighted. The problems encountered when selecting appropriate indicator compounds for rapid toxaphene screening are also addressed.

Development of a reference dose for the persistent congeners of weathered toxaphene based on in vivo and in vitro effects related to tumor promotion

“…There has been considerable and continuing debate over the appropriate analytical methods for WT (de Geus et al, 2000). The key message here is that it will likely be necessary to know the concentration of P 3PC for risk assessment and this concentration needs to be related to the total WT concentration.…”

“…A numerical comparison and sample calculations are provided in Section 4. In addition, the analytical methods used need to be considered; different methods give different analytical results (de Geus et al, 2000) 2. Derivation of a reference dose for tumor promotion based on appearance of GSTp-AHF in rat liver…”

“…Once in the environment, TT undergoes weathering by both biotic and abiotic processes and the number and identity of the congeners in weathered toxaphene (WT) are different than those in TT. Hence, toxaphene has presented a significant challenge to analytical chemists (de Geus et al, 1999(de Geus et al, , 2000. In addition, WT appears to have toxicity characteristics that are different from TT.…”

Environmental Occurrence, Analysis, and Toxicology of Toxaphene Compounds

“…Most attention has been devoted to measuring the EFs of B[12012]- (202) (130) and de Geus et al (125) show that other compounds can be much more interesting 'Enantiomer fraction is the abundance of the first eluting enantiomer relative to the abundance of the sum of both enantiomers (126). hData from Kallenborn et al (124).…”

“…In addition, because of the reciprocal-like scale, ERs larger than unity appear to deviate more than ERs smaller than unity (e.g., 6.7 and 5.0 vs 0.15 and 0.20). To avoid these disadvantages, the (+)-enantiomer or the first eluting enantiomer can be expressed as a proportion of the sum of the two (126 (127,128) successfully used such an approach to study the a-chiral biotransformation of toxaphene congeners by microsomes from harbor seal, whitebeaked dolphin, sperm whale, and laysan albatross.…”