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- Livingstone, D R, et al.
(författare)
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Development of hepatic CYP1A and blood vitellogenin in eel (Anguilla anguilla) for use as biomarkers in the Thames Estuary, UK.
- 2002
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Ingår i: Marine environmental research. - 0141-1136. ; 50:1-5, s. 367-71
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Tidskriftsartikel (refereegranskat)abstract
- The potential of eel (Anguilla anguilla) as a monitoring species for the Thames Estuary, UK, was examined. Hepatic cytochrome P4501A [7-ethoxyresorufin O-deethylase (EROD) activity] and blood vitellogenin (Western analysis) were investigated as biomarkers of exposure to, respectively, organic contaminants and to contaminants showing estrogenic activity. Hepatic microsomal EROD activities in A. anguilla from seven sites in the Thames Estuary in May 1998 varied three-fold (111 +/- 24 to 355 +/- 42 pmol min-1 mg protein-1) (mean +/- S.E.M.) and showed correlation with salinity; however, the latter relationship was not maintained at other times of the year. The range of EROD activities was two- to eight-fold higher than the 37 +/- 8 pmol min-1 mg-1 for A. anguilla from the relatively clean Tamar Estuary. beta-Naphthoflavone treatment (5 mg kg-1 wet wt.; 2 days) of Thames A. anguilla produced a two-fold increase in hepatic microsomal EROD activity. Comparing the Thames EROD data with those for A. anguilla from well-characterised contaminated sites in the Netherlands (Van der Oost, R., Goksøyr, A., Celander, M., Heida, H., & Vermeulen, N. P. E. 1996. Aquatic Toxicology, 36, 189-222), the Thames is suggested to be moderately impacted by polycyclic aromatic hydrocarbons and related contaminants. 17-beta-Estradiol treatment produced the appearance of a plasma protein of 211 Kd app. mol. wt. (recognised by antibodies to vitellogenin of Morone saxatilis), but putative vitellogenin could not be detected in A. anguilla from selected sites in the Thames Estuary.
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| 2. |
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| 3. |
- Åkerblom, N, et al.
(författare)
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Impact of Polychlorinated Naphthalenes (PCNs) in Juvenile Baltic Salmon, Salmo salar: Evaluation of Estrogenic Effects, Development, and CYP1A Induction
- 2000
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Ingår i: Archives of Environmental Contamination and Toxicology. - : Springer Science and Business Media LLC. - 0090-4341 .- 1432-0703. ; 38:2, s. 225-33
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Tidskriftsartikel (refereegranskat)abstract
- Juvenile Baltic salmon, Salmo salar, were fed commercial salmon food contaminated with different concentrations of polychlorinated naphthalenes (PCNs; 0.1, 1, 2, or 10 μg PCN/g food). Among other effects, possible estrogenic impact caused by PCNs were evaluated. Fish were therefore fed a diet contaminated with 17β-estradiol (E2; 0.94 or 9.4 μg E2/g food), as a positive control. After 8, 13, 17, and 41 weeks, sampling took place. Growth, liver somatic index (LSI), EROD activity, and vitellogenin content in blood plasma were measured along with morphological studies of gonads and chemical analyses to determine the effects caused by PCNs. Exposure to PCNs did not seem to have any effects on body weight gain, since the group fed the high dose followed the growth in the control group during the entirely experimental period. After 41 weeks of exposure the groups fed 2 and 10 μg PCN/g food had significantly lower LSIs compared with the control, indicating liver toxic effects of PCNs. Furthermore, a dose-dependent induction of EROD activity was found. At week 41, the control group had an activity of 4.9 ± 4.8 pmol/mg prot/min, whereas it was between 69 ± 21 and 720 ± 370 pmol/mg prot/min in the exposed groups, respectively. Examination of gonadal morphology showed that PCNs also had negative effects on ovaries in Baltic salmon, including delayed development. The distribution between females and males, gonadal morphology, and vitellogenin content in blood plasma did, however, indicate that PCNs are not capable of causing effects similar to E2 or xenoestrogens. Exposure to both of the concentrations of E2 resulted in decreased body weight gain, increased LSI, and feminization of the gonads. E2 did, however, not induce any EROD activity.
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| 5. |
- Sandin, Per, et al.
(författare)
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Precautionary defaults - A new strategy for chemical risk management
- 2004
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Ingår i: Human and Ecological Risk Assessment. - : Informa UK Limited. - 1080-7039 .- 1549-7860. ; 10, s. 1-18
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Tidskriftsartikel (refereegranskat)abstract
- In order to give adequate support to risk managers, new risk assessment methods should be developed that are (1) scientifically sound, (2) simplified, and (3) suited for precautionary risk management. In this Perspective we propose that the notion of a precautionary default can be a useful tool in the development of such methods. A precautionary default is a cautious or pessimistic assumption that is used in the absence of adequate information and that should be replaced when such information is obtained. Furthermore, we point out some promising research areas for the development of such indicators, viz. connections between chemical characteristics such as persistence and effect parameters, monitoring of contaminants in polar regions, monitoring of contaminants in breast milk, application of results from (human) toxicology in ecotoxicology and vice versa, (eco) toxicological test systems that are sensitive to effects on reproduction, and the application of bioinformatic methods to complex data, both in genomic research and in ecotoxicology. We conclude that precautionary decision-making does not require less science, but to the contrary it requires more science and improved communication between scientists and risk managers.
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