|A High Throughput Method for the Analysis of Lewisite Metabolites in Urine.|
|Mon 3:00 PM - Session: Environment and Chemical Disaster|
|A high throughput method for the determination of Lewisite [dichloro(2-chlorovinyl)arsine] exposure by measuring the metabolite 2-chlorovinylarsonous acid (CVAA) by liquid chromatography-inductively coupled plasma-mass spectrometry (LC-ICP-MS) method has been developed. Standard/sample preparation was performed by diluting 400 microliters of urine and 40 microliters of spike standard/water with 1,000 microliters of diluent (12 mM tetrabutylammonium hydroxide, 5 mM succinic acid, 2 % v/v isopropyl alcohol, 200 ppb acetoarsonic acid (AsAc) internal standard, pH 5.5). The samples were centrifuged for four minutes at 1.6 x 104 revolutions per minute and the supernatant was transferred to an autosampler vial. Isocratic elution of CVAA yielded a retention factor of ~three on a reverse phase-polar embedded column with a cycle time of four minutes per sample. Use of the dynamic reaction cell (DRC), typically used to remove isobaric interferences was not required. One hundred samples in a ten hour work day can be analyzed including calibration standards, quality control samples and blanks.
The method demonstrates linearity over at least three orders of magnitude and had a limit of detection of ten ppb as arsenic. The relative standard deviation of quality control samples ranged from 3 to 7 % with recoveries of 98-100%. The developed method is sensitive and selective with zero false positives in 100 different blank samples analyzed before instrument intervention. The described method offers a rapid, accurate and quantitative way to determine lewisite exposure.