Method 8280B Solids
Polychlorinated Dibenzodioxins (PCDDs) and Polychlorinated Dibenzofurans (PCDFs) by High Resolution Gas Chromatography/Low Resolution Mass Spectrometry (HRGC/LRMS)
This method is for the determination of 2,3,7,8-tetrachlorinated dibenzo-p-dioxin (2,3,7,8-TCDD), 2,3,7,8-tetrachlorinated dibenzofuran (2,3,7,8-TCDF), and the 2,3,7,8-substituted penta-, hexa-, hepta-, and octachlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) in soil, fly ash, and chemical waste samples at part-per-billion (ppb) concentrations. The sample is extracted with a combination of a Dean-Stark water trap and Soxhlet extractor using toluene. Soil, fly ash, and other solids may also be extracted using pressurized fluid extraction (PFE) by Method 3545 or microwave extraction by Method 3546. After extraction C13-labeled standards are spiked into the sample to monitor clean-up efficiency. Clean-up options for the extracts are an acid-base wash, gel permeation, alumina, silica gel and Florisil column clean-ups. After clean-up the extract is concentrated and analyzed by high resolution gas chromatography/low resolution mass spectrometry (HRGC/LRMS).
This is an isotope dilution method.
A calculation of the TEQ (toxicity equivalent concentration) is done for each sample using international toxicity equivalency factors (TEFs). A high TEQ, greater than 0.7 ppb for soils and fly ash or 7 ppb for chemical wastes, will require analysis on a second GC column unless 2,3,7,8-TCDF is separated from its closest eluting isomers from analysis on the primary column.
This method replaces Methods 8280 and 8280A.