| 1. |
- Agrell, Cecilia, et al.
(författare)
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PCB congeners in precipitation, wash out ratios and depositional fluxes within the Baltic Sea region, Europe
- 2002
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Ingår i: Atmospheric Environment. - 1352-2310. ; 36:2, s. 371-383
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Tidskriftsartikel (refereegranskat)abstract
- Concentrations of PCB congeners were determined in precipitation and the annual and seasonal depositional fluxes were calculated for 16 (mostly rural) stations around the Baltic Sea during 1990-1993. The concentrations of individual congeners in precipitation were found to be influenced by atmospheric concentrations of PCBs, ambient temperature, precipitation volume and physico-chemical properties of the compounds. Median levels of PCBs in precipitation differed one order of magnitude between stations. When analyzing all data together to obtain regional trends, concentrations of PCBs in precipitation decreased with increasing temperature. This relationship was the same for all stations but differed in the magnitude of the slope for individual congeners. Low chlorinated PCB congeners showed steeper slopes for the temperature relationship than did high chlorinated congeners, a result explained by high atmospheric concentrations of the low chlorinated congeners during low temperatures. Annual wash out ratios were between 31 and 72 x 103 and tended to be higher for the high chlorinated congeners. Wash out ratios decreased with increasing temperature for all congeners except PCB-33. At snow scavenging events, the wash out ratio of PCBs increased with a factor of 2. Latitudinal trends for PCB concentrations in precipitation and deposition were generally not statistically significant. The calculated yearly deposition of PCBs to the Baltic Sea was 390 and 5-18 kg for individual congeners, with PCB-138 having the highest flux. Deposition of PCB congeners varied seasonally, with a factor between 2 and 3, and was generally highest during fall. Relatively higher deposition of low chlorinated congeners compared to high chlorinated congeners was found during winter. (C) 2002 Elsevier Science Ltd. All rights reserved.
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| 2. |
- Agrell, Cecilia, et al.
(författare)
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Polybrominated diphenyl ethers (PBDES) at a solid waste incineration plant I: Atmospheric concentrations
- 2004
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Ingår i: Atmospheric Environment. - : Elsevier BV. - 1352-2310. ; 38:30, s. 5139-5148
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Tidskriftsartikel (refereegranskat)abstract
- In the first of two papers, the atmospheric poly brominated diphenyl ether (PBDE) concentrations at a municipal solid waste incineration (MSW) plant with electronic recycling is compared with that at an industrial urban reference site producing asphalt and concrete. In the second paper, atmospheric deposition and washout behaviour is presented (Atmos. Environ. (2004a)). PBDEs (BDE28, -47, -66, -100, -154, -153, -183, -209) in the gaseous and particulate phase were measured with high resolution in time during the colder parts of the year to minimise the influence of potential historical pollution at the sites through volatilisation. This also means that reported levels are lower compared to other reported data. Results of BDE47 (TetraBDE) and BDE209 (DecaBDE) as representatives of "old" vs. "new" PBDEs as well as SigmaPBDE, excluding BDE209, are presented. Median SigmaPBDE, BDE47 and BDE209 concentration were 6.3, 2.1 and 10.4 pg m(-3) at the MSW and 3.5, 1.7 and 6.5 pg m-3 at the reference site. The total concentrations (gaseous and particulate phase) were significantly higher at the MSW compared to the reference site for SigmaPBDE and BDE47 but not for BDE209. The same results were obtained regarding concentrations in the gaseous phase. Particle concentrations were significantly higher at the MSW for SigmaPBDE, BDE47 and BDE209. Within each site, the gaseous-phase concentration was significantly higher than the particulate-phase concentration except for BDE209 at the MSW. Thus, the proportion of BDE209 detected in the particulate phase was higher at the MSW compared to the reference site. Together with the results of the second paper, we suggest that treatment of waste is presently a source of "old" PBDEs to the environment, whereas the rather similar BDE209 concentrations at the two sites are more a result of proximity to potential diffuse sources.
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| 3. |
- ter Schure, Arnout, et al.
(författare)
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Polybrominated diphenyl ethers at a solid waste incineration plant II: atmospheric deposition
- 2004
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Ingår i: Atmospheric Environment. - : Elsevier BV. - 1352-2310. ; 38:30, s. 5149-5155
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Tidskriftsartikel (refereegranskat)abstract
- In the second of two papers, the atmospheric polybrominated diphenyl ethers (PBDE) deposition (wet and dry) at a municipal solid waste incineration (MSW) plant with electronics recycling is compared with that at an industrial urban reference site (URS) producing asphalt and concrete. Results of BDE209 and SigmaPBDE excluding BDE209 as representatives of "new" vs. "old" PBDEs are presented. Volume weighted mean SigmaPBDE and BDE209 concentrations at the MSW were 6.2 and 14.4 ng l(-1), and at the URS were 2.5 and 14.1 ng l(-1). Median SigmaPBDE and BDE209 deposition fluxes were 21.3, 63.8 and 7.0, 14.7 ng m(-2) day(-1) at the MSW and URS, respectively. The concentrations in precipitation and the deposition fluxes were significantly higher at the MSW compared to the URS. Measured total washout- ratios (W-T) were dependent on particle scavenging and the median WT for all congeners was 5.4x 10(5). Median dry particle deposition velocities ranged from 0.4 to 49 cm s(-1), depending on congener, showing that PBDEs are effectively removed from the atmosphere by particle deposition. PBDE fluxes increased at the reference site when winds were blowing from west south-west, i.e. from the direction of the MSW. PBDE deposition and washout ratios were not influenced by temperature or rain volume, suggesting a constant emission from the MSW regardless of weather conditions. Together with the results of paper I (Agrell et al., 2004, Atmospheric Environment, this issue) we therefore suggest that treatment of waste, e.g. electronics recycling, is more a source of "old" PBDEs to the environment, whereas the rather similar BDE209 concentrations at the two urban sites are more a result of proximity to potential diffuse sources. (C) 2004 Elsevier Ltd. All rights reserved.
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