Evaluation of methodology for determination of polyhalogenated dibenzo-p-dioxins and dibenzofurans in ambient air

General Metals Works PS-1 PUF air samplers and an analytical method based on high resolution gas chromatography - high resolution mass spectrometry (HRGC-HRMS) were evaluated for determination of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/PCDFs) and polybrominated dibenzo-p-dioxins and dibenzofurans (PBDDs/PBDFs) in ambient air. Dilute solutions of these compounds and 13C12-1234-TCDD were used to spike the filters of PS-1 air samplers which were then operated 24 hours to sample 350-400 cu m ambient air. After sampling, each quartz-fiber filter and polyurethane foam (PUF) were spiked with 13C12-labeled PCDD, PCDF, PBDD, and PBDF internal standards before separate Soxhlet extractions with benzene. The extracts were subjected to clean-up procedures using microcolumns of silica gel, alumina and carbon and then analyzed by HRGC-HRMS. Results derived from this study satisfied QA/QC requirements for analytical data and demonstrated that the methodology could accurately determine pg/cu m and sub-pg/cu m levels of these compounds in ambient air. Background levels detected in ambient air are also discussed.