| 1. |
- J. Tranvik, Lars, et al.
(författare)
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In situ mineralization of chlorinated phenols by pelagic bacteria in lakes of differing humic content
- 1991
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Ingår i: Environmental Toxicology and Chemistry. - : Wiley. - 0730-7268 .- 1552-8618. ; 10:2, s. 195-200
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Tidskriftsartikel (refereegranskat)abstract
- The microbial mineralization of phenol and three chlorinated phenols (3,4-dichlorophenol, 2,4,5-trichlorophenol and pentachlorophenol) in the water column of 23 pristine, oligotrophic lakes of different humic content was investigated. During short-term (∼2 d) in situ incubations of water samples amended with 14C-labeled phenolic compounds, the fraction of the added pollutant mineralized to 14CO2 was positively correlated with water color (an estimate of humic content) and the total organic carbon concentration of the water. The rate of mineralization per bacterial cell was not correlated with humic content, due to increased bacterial abundance with increasing humic content. Hence, the higher mineralization rate in humic lakes than in clear-water lakes was probably a result of higher bacterial abundance rather than being an effect of bacterial cells having a higher potential for the degradation of such compounds.
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| 2. |
- Larsson, Per, et al.
(författare)
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Reproductive status and lipid content as factors in PCB, DDT and HCH contamination of a pike population (Esox lucius L.)
- 1993
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Ingår i: Environmental Toxicology and Chemistry. - 0730-7268. ; 12:5, s. 855-861
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Tidskriftsartikel (refereegranskat)abstract
- Levels of persistent pollutants, including PCBs, SIGMADDT, and gamma-hexachlorocyclohexane, were examined in a pike population inhabiting a eutrophic lake in southern Scandinavia. For females, levels of persistent pollutants decreased linearly with age, weight, or length. This decline was ascribed to the seasonal elimination of the lipophilic pollutants in roe, which contained up to 10 times higher fat levels compared to muscle and over 10 times the amounts of pollutants. Male pike contained higher levels of pollutants than females, probably due to the lower elimination via gonadal products, as germinal tissue constitutes only 2% of the male total body weight and has a lower fat content than ovaries. Female germinal tissue can account for as much as 15% of the body weight. No major fat deposits other than those in germinal tissue were found in pike, which also had a low muscle fat content, suggesting that the importance of roe elimination in removing pollutants may be greater in pike than in salmonids. Uptake of persistent pollutants can vary greatly within a species, owing to differences in sex, age, and so forth, as well as between species, owing to differences in fat deposition strategies.
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| 3. |
- Tranvik, Lars, et al.
(författare)
-
In-situ mineralization of chlorinated phenols by pelagic bacteria in lakes of differing humic content
- 1991
-
Ingår i: Environmental Toxicology and Chemistry. - 0730-7268. ; 10:2, s. 195-200
-
Tidskriftsartikel (refereegranskat)abstract
- The microbial mineralization of phenol and three chlorinated phenols (3,4-dichlorophenol, 2,4,5-trichlorophenol and pentachlorophenol) in the water column of 23 pristine, oligotrophic lakes of different humic content was investigated. During short-term (approximately 2 d) in situ incubations of water samples amended with C-14-labeled phenolic compounds, the fraction of the added pollutant mineralized to (CO2)-C-14 was positively correlated with water color (an estimate of humic content) and the total organic carbon concentration of the water. The rate of mineralization per bacterial cell was not correlated with humic content, due to increased bacterial abundance with increasing humic content. Hence, the higher mineralization rate in humic lakes than in clear-water lakes was probably a result of higher bacterial abundance rather than being an effect of bacterial cells having a higher potential for the degradation of such compounds.
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