| Abstract
| - Soil extracts from five Superfund Contract LaboratoryProgram (CLP) laboratories were analyzed for organochlorinepesticides using gas chromatographic separation withion trap mass spectrometric detection in both electronimpact (GC/EIMS) and tandem mass spectrometry (GC/MS/MS) modes. These results were compared with thosefrom the standard CLP dual-column gas chromatographyelectron capture detection (GC/ECD) pesticide method. Thiswas accomplished to (a) determine the number of falsepositives and false negatives in the CLP data, (b) evaluateion trap GC/MS/MS as a potential technique to replace/augment conventional ECD-dual-column methodology, and(c) to compare conventional ion trap GC/EIMS with therelatively new ion trap GC/MS/MS. In all, 16 pesticide extractsfrom five CLP laboratories were analyzed for 20 pesticidesby GC/EIMS and GC/MS/MS, and the data were comparedwith the results from the CLP method (ECD-dual-columnpesticide method). Of a possible 960 parameters (20analytes × 16 samples × 3 data sets), there were 253detections with concentrations ranging from 1 pg/μL to 77 ng/μL. The respective number of false positives and falsenegatives were 27 and 1 for GC/MS/MS, 6 and 10 for GC/EIMS, and 25 and 9 for the CLP data. Causes of erroneousresults are discussed.
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