Assessing the contribution of diffuse domestic burning as a source of PCDD/Fs, PCBs, and PAHs to the UK atmosphere

Ambient air samples were taken concurrently at four sites in northwest England to assess the role of domestic burning of coal/wood on ambient levels of PCDD/Fs, PCBs (including co-PCBs), and PAHs. Fifty-six samples (ca, 800 m(3) each) were taken in January and February 1998 at an urban site, a rural reference site, and two village sites, which relied on domestic burning for space heating. Correlations with meteorological parameters found the urban site to he a source area of all POPs investigated, while the village sites had a local impact of PAHs and, to a lesser extent, PCDD/Fs. PCDD/F-levels changed simultaneously at all sites, pointing toward a combination of regional meteorological effects and increased domestic burning. Two sampling events, marked by low ambient temperatures a nd wind speeds, showed substantial increases in PCDD/F and PAH concentrations (by factors of 2-5). We estimate that local sources at the villages accounted for similar to 25% of the Sigma TEQ (with similar to 75% stemming from advective transport) and similar to 75% of the Sigma PAHs in the ambient air at those sites (similar to 25% advective transport) during our winter sampling events. This study singled out PCDFs, notably the lower chlorinated ones, as good indicators of domestic burning, together with a range of PAHs. The co-PCBs #126 and 169 were found to behave like PCDD/Fs and PAHs rather than the more abundant "regular" PCBs, confirming that they have different sources to the environment.