Superfund contract laboratory program method evaluation — ambient air volatile organic compounds from canisters

Abstract

A GC/MS system that is modified for the addition of internal standards has been used to run the Superfund method for volatile organic compounds in ambient air as described in the Statement of Work for the Superfund Contract Laboratory Program/Statement of Work (CLP/SOW). The analysis method applies to air samples retrieved from GL (SUMMA‐polished) stainless steel canisters. Generic performance criteria were tested by using full‐scan mass spectrometry. The method quantitation limit was determined to be less than the contract‐required quantitation limit (CRQL) for 37 of the 41 target compounds; replicate analyses of field samples achieved CLP/SOW‐specified values of precision (±25% difference relative to the average value for two analyses) for all target gas concentrations above the CRQLs; and audit accuracy values at a nominal 5‐ppb_v concentration averaged 9.6% unsigned average relative percentage difference. Field tests at the French Limited Super‐fund site near Crosby, Texas, support the choice of the scanning mode of mass spectrometer operation in that many nontargeted compounds occur at high concentrations. However, method quantitation limits for targeted compounds are increased by factors ranging from five to ten from those obtainable in the selected ion monitoring mode.