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- Larsson, Per
(author)
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Atmospheric deposition of persistent pollutants governs uptake in freshwater zooplankton
- 1989
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In: Atmospheric Environment. - : Elsevier BV. - 1352-2310 .- 1873-2844 .- 0004-6981. ; 23:10, s. 2151-2158
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Journal article (peer-reviewed)abstract
- The atmospheric fallout of PCBs, ∑DDT and γ-HCH (lindane) to a pond in southern Sweden was studied in relation to uptake by freshwater Zooplankton. The extent of the atmospheric deposition of PCBs and lindane was reflected in the uptake by the Zooplankton; high deposition in the spring and autumn resulted in high uptake by the organisms while a lower uptake during summer was a result of lower deposition. The atmospheric deposition of ∑DDT was dominated by p,p-DDT, p,p-DDE and o,p-DDT, while p,p-DDE and p,p-DDD were dominant in Zooplankton. These differences in ∑DDT composition are probably attributed to microbial conversion; as a result, levels in the Zooplankton appeared not to be governed by atmospheric deposition. The availability of the previously airborne, persistent pollutants to Zooplankton was a function of the compounds chemical properties, e.g. water solubility, and the form of deposition. The results show that atmospheric deposition is an important route by which persistent pollutants are transported to Holarctic, aquatic ecosystems.
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2. |
- Larsson, Per, et al.
(author)
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Atmospheric transport of chlorinated hydrocarbons to Sweden 1985 compared to 1973
- 1989
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In: Atmospheric Environment. - : Elsevier BV. - 1352-2310 .- 1873-2844 .- 0004-6981. ; 23:8, s. 1699-1711
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Journal article (peer-reviewed)abstract
- The atmospheric fallout of DDT and DDE (ΣDDT) over Sweden has decreased during the last decade. Today long-range transport from southern sources outside the country dominates the inflow. This was reflected in a decreasing south-to-north gradient of the compounds in atmospheric deposition and in the lower atomosphere. The fallout of PCBs was similar in 1984–1985 and 1972–1973, and today local contamination by combustion is more prominent than it was 10 years ago, even though PCB restrictions have been in force during the interim. Since PCB deposition is higher in the coastal areas than in the inland regions, other sources, such as volatilization from the seas and long-range transport also contribute to PCBs in fallout. The levels of PCB and ΣDDT in the lower atmosphere were positively correlated with temperature. Consequently, the compounds tended to be in the gas phase during the warmer summer period whereas during winter they were more liable to be adsorbed to particles, partition to airborne water and contribute in fallout. From each sampling station a chromatographic 'fingerprint' of pollutants in airborne fallout and in the lower atmosphere was obtained. The fingerprint was the combined result of the station's location and climate. The results show that considerable amounts of chlorinated pollutants are being transported to and within Sweden via the atmosphere.
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