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- Larsson, D. G. Joakim, 1969, et al.
(författare)
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Ethinyloestradiol – an undesired fish contraceptive?
- 1999
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Ingår i: Aquatic Toxicology. - 0166-445X .- 1879-1514. ; 45:2-3, s. 91-97
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Tidskriftsartikel (refereegranskat)abstract
- Environmental oestrogens are natural or synthetic substances present in the environment, which imitate the effects of endogenous oestrogen. Oestrogenic substances were identified by gas chromatography/mass spectrometry in effluent water from a Swedish sewage treatment works receiving mainly domestic wastewater. Substances found include the synthetic oestrogen used in contraceptives 17 alpha-ethinyloestradiol (4.5 ng l(-1)), the natural oestrogens oestrone (5.8 ng l(-1)) and 17 beta-oestradiol (1.1 ng l(-1)), and the weaker non-steroidal oestrogens 4-nonylphenol (840 ng l(-1)) and bisphenol A (490 ng l(-1)). Ethinyloestradiol exceeded levels shown to be oestrogenic to fish by 45 times. The oestrogenicity of the effluent water was investigated by introducing juvenile rainbow trout (Oncorhynchus mykiss) in cages downstream of the sewage treatment works. After 2 weeks, all oestrogens indicated were present in the bile of the fish, and the oestrogen inducible protein, vitellogenin, was found in large amounts in the plasma (1.5 mg ml(-1)), as determined by enzyme-linked immunosorbent assay and Western blotting. Thus, a widely used synthetic oestrogen affects the endocrine systems of fish exposed to sewage effluent water.
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| 2. |
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| 3. |
- Ronisz, Dan, et al.
(författare)
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Seasonal variations in the activities of selected hepatic biotransformation and antioxidant enzymes in eelpout (Zoarces viviparus).
- 1999
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Ingår i: Comparative biochemistry and physiology. Part C, Pharmacology, toxicology & endocrinology. - 1367-8280. ; 124:3, s. 271-9
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Tidskriftsartikel (refereegranskat)abstract
- The eelpout (Zoarces viviparus) is used in Swedish and German environmental monitoring of pollutant effects in fish and is being considered for the same purpose in other countries, mainly around the Baltic Sea. The activities of several hepatic biotransformation and antioxidant enzymes were monitored during the period of 12 months from August 1996 to July 1997, using newly caught feral eelpout from Kattegat, off the west coast of Sweden. In females, the biotransformation enzyme activities showed significant seasonal variations, although the amplitude of the changes was limited; CYP1A-activity, measured as ethoxyresorufin-O-deethylase (EROD), was highest in February-March and decreased afterwards, possibly due to rising estrogen levels. UDP-glucuronosyltransferase activity was lowest in November, while the glutathione-S-transferase activity markedly decreased during the winter. The antioxidant enzymes, catalase, glutathione peroxidase and glutathione reductase showed small variations in their activity. The number of male fish was limited and the seasonal variations less clear. However, in both sexes, glutathione reductase and peroxidase activities were highest in autumn and May, respectively. This study establishes a baseline for the activities of the selected enzymes in female eelpout, which is important for the environmental monitoring using this fish species.
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