Baseline contamination assessment for a new resource recovery facility in Germany part II: atmospheric concentrations of PCDD/F

The atmospheric levels of PCDD/Fs in both the gas and particle phases were measured continuously over 1 year at 7 sites in the outskirts of Augsburg, Germany, and at a rural site 15 km from the city. The homologue and congener patterns in the total air samples were similar among the different stations and stayed constant throughout the whole year. The PCDD/F levels were about two times higher at the sampling points on the edge of the city than at the remote location. There was a pronounced temporal variability of the total air concentrations, with levels in winter that were 9 times higher than the levels in summer. The gas/particle partitioning was characterised by higher gaseous fractions for more volatile compounds and higher ambient temperatures. It was concluded that the ambient air concentrations of the PCDD/Fs are determined by on-going local and regional emissions, with seasonal (winter) sources contributing the vast majority of the emissions fluxes.