Publication Abstract

A survey of oestrogenic activity in UK estuarine and coastal waters and its effects on gonadal development of the flounder

Y. Allen, A.P. Scott, P. Matthiessen, S. Haworth, J.E. Thain and S.W. Feist

Estrogenic discharges are known or suspected to be present in many UK estuaries and are also occuring from offshore oil and gas installations. The main aim of this study was to establish whether estrogens and their mimics are presnt in marine waters at concentrations which can produce biological responses in fish, and if so, to discover whether the effects are likely to be harmful to populations and communities through changes in reproductive and other physiological processes. Both laboratory studies and extensive field surveys were carried out with the euryhaline flounder (Platichthys flesus), using the amount of yolk protein in the blood of free-living male fish as an indicator of exposure to estrogens. Exposure to the synthetic estogen ethynylestradiol for three weeks confirmed that the fish were able to make the vitellogenin response and showed that this species is approximately one order of magnitude less than the freshwater species rainbow trout. The fish did not respond to the estrogen mimic nonyphenol at concentrations of 30 gg/L. Wild male flounder were sampled from four contaminated UK estuaries, the Tyne, Crouch, Thames and Mersey. Fish from one or more sites in each estuary had significantly elevated concentrations of vitellogenin in their blood when compared to concentrations in fish from the clean control (River Alde). Vitellogenin concentrations in the Tyne and Mersey were 4 and 6 orders of magnitude greater, respectively, than control concentrations. Elevated vitellogenin concentrations were also seen in some male flounder caught in coastal areas. Approximately 20% of male fish from the Mersey estuary contained oocytes in their testes, but this intersex condition was not seen elsewhere. The implications of these findings for fish populations are discussed.

Reference:

Y. Allen, A.P. Scott, P. Matthiessen, S. Haworth, J.E. Thain and S.W. Feist, 1999. A survey of oestrogenic activity in UK estuarine and coastal waters and its effects on gonadal development of the flounder. Environmental Toxicology and Chemistry, 18(8): 1791-1800