ORIGINAL PAPER Toxaphene analysis in Great Lakes fish: a comparison of GC-EI/MS/MS and GC-ECNI-MS, individual congener standard and technical mixture for quantification of toxaphene Xiaoyan Xia & Bernard S. Crimmins & Philip K. Hopke & James J. Pagano & Michael S. Milligan & Thomas M. Holsen Received: 12 June 2009 / Revised: 10 July 2009 / Accepted: 16 July 2009 / Published online: 31 July 2009 # Springer-Verlag 2009 Abstract Toxaphene is considered to be a problematic organochlorine pollutant because of its bioaccumulation potential and persistence in aquatic environments. In this study, whole lake trout and walleye composites were used to evaluate two analytical techniques for total toxaphene and selected congener analysis. The efficacy of using gas chromatography electron ionization tandem mass spectrome- try (GC-EI/MS/MS) and electron capture negative ionization mass spectrometry (GC-ECNI-MS) were compared. Al- though the sensitivity using GC-ECNI-MS was approximate- ly five times greater than GC-EI/MS/MS, the latter provided more consistent inter-Parlar relative response factors (RRF). When using technical calibration mixtures, these results suggest a more accurate total toxaphene measurement was obtained using the GC-EI/MS/MS method. Total toxaphene concentrations in lake trout composites from both methods were highly correlated (R 2 =0.985) with the MS/MS concen- trations approximately half of those determined by ECNI, suggesting systematic high bias in toxaphene concentrations when measured using GC-ECNI. Keywords Toxaphene . Great Lakes . Gas chromatography coupled with electron ionization tandem mass spectrometry (GC-EI/MS/MS) . Gas chromatography/electron capture negative ion mass spectrometry (GC-ECNI-MS) . Fish tissue Introduction Toxaphene is a chlorinated pesticide mixture including mainly chlorinated bornanes and chlorinated bornenes. It was introduced in the United States by the Hercules Company in the late 1940s and was heavily used in the southern United States on cotton fields. Once applied, toxaphene can volatilize into the air where it can be transported to and deposited in regions far from where it was applied. As a result, toxaphene has been found in the air, rain, water, sediment, and fish in the Great Lakes region [1–10]. Toxaphene is considered carcinogenic [11] based on the data collected in toxicity studies in rats and other mammals. It is assumed to present a high risk for human health [12]. Human exposure to toxaphene occurs mainly through occupational exposure and the consumption of contaminated fish. Occupational exposure is now rare because toxaphene was banned by the U.S. EPA in 1982. Toxaphene is one of the organic contaminants monitored in the Great Lakes Fish Monitoring Program (GLFMP). The X. Xia : B. S. Crimmins Center for Air Resource Engineering and Science, Clarkson University, Potsdam, NY 13699, USA P. K. Hopke (*) Department of Chemical and Biomolecular Engineering, Clarkson University, CAMP Room 220, PO Box 5705, Potsdam, NY 13699-5705, USA e-mail: hopkepk@clarkson.edu J. J. Pagano Environmental Research Center, State University of New York at Oswego, Oswego, NY 13126, USA M. S. Milligan Department of Chemistry and Biochemistry, State University of New York at Fredonia, Fredonia, NY 14063, USA T. M. Holsen Department of Civil & Environmental Engineering, Clarkson University, Potsdam, NY 13699, USA Anal Bioanal Chem (2009) 395:457–463 DOI 10.1007/s00216-009-2988-1