Assessment of the physiological impact of endocrine disrupting chemicals on salmonid fish from selected sites in Scotland and Northern Ireland

• Main Authors: Pottinger, T.G., Carrick, T.R., Lyle, A.A., Rosell, R., Nolan, M., Scott, A.P.
• Format: Report
• Language: English
• Published: SNIFFER 2001
• Subjects: Ecology and Environment; Zoology; Biology and Microbiology; Atlantic salmon
• Online Access: http://nora.nerc.ac.uk/id/eprint/512345/; https://nora.nerc.ac.uk/id/eprint/512345/1/Sniffer%20Final%20Report%20SR%200003%20-%202001.pdf; http://www.sniffer.org.uk/index.php/download_file/711

1. Recent research in the UK and elsewhere has demonstrated that industrial and domestic effluents may contain compounds of both natural and synthetic origin which are steroid estrogens, or mimic the activity of steroid estrogens. Although present in solution at very low concentrations the sensitivity of the endocrine system of animals to interference is such that these contaminants represent a potentially disruptive threat. 2. A survey of gonadal structure in roach populations in English rivers revealed that a high proportion (25% – 60%) of male fish within the sampled populations displayed evidence of abnormal gonadal development in the form of ovarian tissue within the testes. These effects were most pronounced at sites where discharged effluents represented a high proportion of total flow in the river. The functional significance of these observations has yet to be established. 3. Concerns have been raised regarding the possible susceptibility of valuable salmon and trout populations to endocrine disruptive processes. This report describes the results of a fieldbased investigation of indicators of estrogen exposure in salmonid fish exposed to potentially estrogenic effluent discharges at sites in Scotland and Northern Ireland. 4. This study addressed the possibility that native salmonid populations are being exposed to estrogenic contaminants via both domestic and industrial discharges and that this exposure may result in inappropriate and possibly detrimental physiological effects in exposed fish. 5. This objective was addressed by the sampling of brown trout and Atlantic salmon from sites receiving a STW discharge and from pristine sites. Blood levels of the estrogen-inducible yolk precursor vitellogenin were measured to assess whether there was evidence that the targeted populations were exposed to acute estrogen exposure. In addition, gonadal material sampled from each fish was examined microscopically for evidence of abnormal reproductive development, the presence of which would be indicative of early ...