title: Spatial Distribution of Atmospheric PCBs in Zurich, Switzerland: Do Joint Sealants Still Matter?
abstract: Passive air samplers were deployed at 23 sites across the city of Zurich, Switzerland to investigate the spatial distribution of polychlorinated biphenyls (PCBs) in air. Concentrations of the six indicator PCBs (iPCBs) in air ranged from 54 to 3160 pg·m(-3) in the two sampling campaigns (spring 2011 and spring 2013). Measurements at two sampling sites were significantly higher than the median in both years, because of the proximity to primary PCB sources. Concentrations at most other stations were in a narrow range, suggesting that atmospheric PCB concentrations in Zurich are mainly caused by a high number of rather small sources. A correlation of iPCB concentrations in air with the number of buildings constructed between 1955 and 1975 in the surrounding areas of the sampling sites was observed. This demonstrates that PCB-containing building materials, such as joint sealants, influence PCB levels in urban air. Additionally, atmospheric iPCB concentrations were measured in the surrounding of a housing complex with PCB-contaminated joint sealants. Using a Gaussian diffusion model, annual iPCB emissions of 110-190 g were calculated for this housing complex. This appreciable amount released by a single building points out that more efforts are required to further eliminate remaining PCB stocks.
authors.affiliation: Institute for Chemical and Bioengineering, ETH Zurich , Vladimir-Prelog-Weg 1, CH-8093 Zürich, Switzerland.|Empa, Swiss Federal Laboratories for Materials Science and Technology , Überlandstrasse 129, CH-8600 Dübendorf, Switzerland.
authors.forename: Pascal S
authors.initials: PS
authors.lastname: Diefenbacher
authors.affiliation: Empa, Swiss Federal Laboratories for Materials Science and Technology , Überlandstrasse 129, CH-8600 Dübendorf, Switzerland.
authors.forename: Andreas C
authors.initials: AC
authors.lastname: Gerecke
authors.affiliation: Institute for Chemical and Bioengineering, ETH Zurich , Vladimir-Prelog-Weg 1, CH-8093 Zürich, Switzerland.|Agroscope, Institute for Sustainability Sciences ISS , Reckenholzstrasse 191, CH-8046 Zürich, Switzerland.
authors.forename: Christian
authors.initials: C
authors.lastname: Bogdal
authors.affiliation: Institute for Chemical and Bioengineering, ETH Zurich , Vladimir-Prelog-Weg 1, CH-8093 Zürich, Switzerland.
authors.forename: Konrad
authors.initials: K
authors.lastname: Hungerbühler
mesh_terms: D000392:Air Movements; D000393:Air Pollutants / Q000032:analysis*; D002947:Cities; D004058:Diffusion; D004784:Environmental Monitoring; D015233:Models, Statistical; D011078:Polychlorinated Biphenyls / Q000032:analysis*; D013557:Switzerland
chemical_list: D000393:Air Pollutants; D011078:Polychlorinated Biphenyls