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- Cornelissen, G, et al.
(författare)
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Black carbon-dominated PCDD/Fs sorption to soils at a former wood impregnation site
- 2008
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Ingår i: Chemosphere. - : Elsevier. - 0045-6535 .- 1879-1298. ; 72:10, s. 1455-1461
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Tidskriftsartikel (refereegranskat)abstract
- The influence of black carbon (BC) on the sorption of 17 native polychlorinated-p-dibenzodioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) was studied in five soil samples from a sawmill site where wood used to be impregnated with chlorophenol preservatives. The presence of BC caused measured total organic carbon (TOC)-water distribution ratios (KTOC) to be a median factor of 51 (interquartile range 18-68, n = 85) higher than modeled amorphous organic carbon (AOC)-water distribution ratios (KAOC). KTOC was a factor of 73 ± 27 above KAOC for PCDFs (n = 10) and a factor of 20 ± 13 (n = 7) for PCDDs. The reason for this difference is probably that attaining a planar configuration after sorption to BC is less thermodynamically favorable for PCDDs than for PCDFs. BC-water distribution ratios were calculated from KTOC, KAOC and BC contents, and ranged from 109.9 (2,3,7,8-Tetra-CDD) to 1011.5 l kg-1 (Octa-CDF). More than 90% of the PCDD/Fs in the soil was calculated to be BC-sorbed. Dissolved organic carbon (DOC)-water distribution ratios were measured to be in the same order of magnitude as KAOC. This study shows that strong sorption to BC should be included when assessing ecotoxicological risk or modeling transport to groundwater of PCDD/Fs in soil.
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| 2. |
- Sundqvist, Kristina, et al.
(författare)
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Receptor Modeling of PCDD/FS in Sediment of the Sundsvall Bay, Sweden
- 2008
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Ingår i: Organohalogen Compounds. ; 70:1641-4
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Tidskriftsartikel (refereegranskat)abstract
- In the Sundsvall Bay area, located in the southern Bothnian Sea (a sub-basin of the Baltic Sea), industrial history have included a large variety of activities, from small sawmills to large pulp and paper mills as well as chloralkali production. Previously, several sawmills in the area used chlorophenol formulations for wood preservation, and these were contaminated by PCDD/Fs. Chloralkali production using graphite electrodes and bleaching of pulp using chlorine are manufacturing processes also known to have caused PCDD/Fs emissions. A chemical industry has been active in the area since the 1930s and an aluminum smelter was built in 1942. Aluminum production, like many high temperature processes, is known to produce PCDD/Fs.The aim of this study was to investigate the possibility of using receptor modeling for identification and apportioning of the major sources of PCDD/Fs in the Sundsvall Bay. The Sundsvall Bay was chosen as the first study area of this modeling technique along the Swedish coast since there are several possible sources of PCDD/Fs in the area and a relatively large number of sediment samples have been analyzed. Current PCDD/F emissions have been investigated by sampling river water, industrial effluent entering the bay and, in addition, soil from two contaminated sawmill sites.
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