title: Laboratory investigation of PCB bake-out from tertiary contaminated concrete for remediation of buildings.
abstract: Polychlorinated biphenyls (PCBs) have been used in flexible construction products from the 1950s to the 1970s. Despite a relatively low vapour pressure, PCBs have over the years emitted to the indoor air and adsorbed to other surfaces, creating tertiary sources. While necessary to protect the environment and health of building occupants, remediation of the contaminated buildings is an expensive and difficult process. The aim of this study was to investigate the effect of bake-out as a method for removing PCB from contaminated indoor surfaces. Four painted and four sandblasted samples of concrete wall were kept at 50 or 65 °C for 10 or 20 days in small scale chambers, which were ventilated with clean air at area specific rates comparable to full scale rooms. The air concentrations were measured several times during the bake-out. Concentrations of PCB in paint, plaster and concrete were measured before and after the experiment. For the painted samples, PCB28 and PCB52 followed by PCB138 and PCB153 were the predominant congeners measured in air. A significant reduction of the PCB concentration was only found for more volatile congeners in paint, while no significant effects were observed in the plaster or concrete. For the most effective setting (65 °C, 20 days), the concentration of PCB∑7in the paint was reduced by 40%. For the sandblasted samples, the less volatile congeners PCB138 and PCB153 were predominant in the air during bake-out. No effect was observed on the initially low concentrations of the sandblasted samples, possibly due to analytical limitations.
authors.affiliation: Department of Energy, Environment and Indoor Climate, Danish Building Research Institute, Aalborg University, A.C. Meyers Vaenge 15, DK-2450 Copenhagen SV, Denmark; Danish Environmental Analysis (Dansk MiljøAnalyse), Skelstedet 5, DK- 2950 Vedbaek, Denmark. Electronic address: bk@dma.nu.
authors.forename: Barbara
authors.initials: B
authors.lastname: Kolarik
authors.affiliation: Department of Energy, Environment and Indoor Climate, Danish Building Research Institute, Aalborg University, A.C. Meyers Vaenge 15, DK-2450 Copenhagen SV, Denmark.
authors.forename: Helle Vibeke
authors.initials: HV
authors.lastname: Andersen
authors.affiliation: Department of Energy, Environment and Indoor Climate, Danish Building Research Institute, Aalborg University, A.C. Meyers Vaenge 15, DK-2450 Copenhagen SV, Denmark; National Research Centre for the Working Environment, Lersø Parkalle 105, DK-2100 Copenhagen Ø, Denmark.
authors.forename: Marie
authors.initials: M
authors.lastname: Frederiksen
authors.affiliation: Department of Energy, Environment and Indoor Climate, Danish Building Research Institute, Aalborg University, A.C. Meyers Vaenge 15, DK-2450 Copenhagen SV, Denmark.
authors.forename: Lars
authors.initials: L
authors.lastname: Gunnarsen
mesh_terms: D016902:Air Pollution, Indoor / Q000032:analysis*; D052918:Environmental Restoration and Remediation / Q000379:methods*; D007753:Laboratories; D010150:Paint / Q000032:analysis; D011078:Polychlorinated Biphenyls / Q000032:analysis*; D013696:Temperature; D013997:Time Factors; D055548:Vapor Pressure
chemical_list: D011078:Polychlorinated Biphenyls
keywords: Building materials; Indoor air; Mitigation; Polychlorinated biphenyls; Tertiary sources; Thermal stripping