Simultaneous detection of the tetrachloroethylene metabolites S-(1,2,2-trichlorovinyl) glutathione, S-(1,2,2-trichlorovinyl)-L-cysteine, and N-acetyl-S-(1,2,2-trichlorovinyl)-L-cysteine in multiple mouse tissues via ultra-high performance liquid chromatography electrospray ionization tandem mass spectrometry

ABSTRACT

Tetrachloroethylene (perchloroethylene; PERC) is a high-production volume chemical and ubiquitous environmental contaminant that is hazardous to human health. Toxicity attributed to PERC is mediated through oxidative and glutathione (GSH) conjugation metabolites. The conjugation of PERC by glutathione-s-transferase to generate S-(1,2,2-trichlorovinyl) glutathione (TCVG), which is subsequently metabolized to form S-(1,2,2-trichlorovinyl)-L-cysteine (TCVC) is of special importance to human health. Specifically, TCVC may be metabolized to N-acetyl-S-(1,2,2-trichlorovinyl)-L-cysteine (NAcTCVC) which is excreted through urine, or to electrophilic metabolites that are nephrotoxic and mutagenic. Little is known regarding toxicokinetics of TCVG, TCVC, and NAcTCVC as analytical methods for simultaneous determination of these metabolites in tissues have not yet been reported. Hence, an ultra-high-performance liquid chromatography electrospray ionization tandem mass spectrometry-based method was developed for analysis of TCVG, TCVC, and NAcTCVC in liver, kidneys, serum, and urine. The method is rapid, sensitive, robust, and selective for detection all three analytes in every tissue examined, with limits of detection (LOD) ranging from 1.8 to 68.2 femtomoles on column, depending on the analyte and tissue matrix. This method was applied to quantify levels of TCVG, TCVC, and NAcTCVC in tissues from mice treated with PERC (10 to 1000 mg/kg, orally) with limits of quantitation (LOQ) of 1–2.5 pmol/g in liver, 1–10 pmol/g in kidney, 1–2.5 pmol/ml in serum, and 2.5–5 pmol/ml in urine. This method is useful for further characterization of the GSH conjugative pathway of PERC in vivo and improved understanding of PERC toxicity.

Acknowledgments

The views expressed in this paper are those of the authors and do not necessarily reflect the views or policies of NIH or EPA. The authors express their gratitude to Dr. Avram Gold from the Department of Environmental Sciences and Engineering, University of North Carolina at Chapel Hill for providing chemical standards and to Drs. Terry Wade and Anthony Knap from the Geochemical Environmental Research Group at Texas A&M University for assistance with analytical instrumentation.

Funding

J.A.C. was a recipient of a National Research Service Award through the National Institutes of Health (F32 ES026005). This work was supported, in part, by a cooperative agreement STAR RD83561202 from US EPA to Texas A&M University.

Supplemental data for this article can be accessed on the publisher’s website.

Additional information

Funding

J.A.C. was a recipient of a National Research Service Award through the National Institutes of Health (F32 ES026005). This work was supported, in part, by a cooperative agreement STAR RD83561202 from US EPA to Texas A&M University.