Survey of Estrogenic Activity in United Kingdom Estuarine and Coastal Waters and Its Effects on Gonadal Development of the Flounder Platichthys Flesus

Abstract

Abstract-Estrogenic discharges are known or suspected to be present in many United Kingdom estuaries and are also occurring from offshore oil and gas installations. The aim of this study was to establish whether estrogens and their mimics are present in marine waters at concentrations that 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. Laboratory studies and extensive field surveys were carried out with the euryhaline flounder (Platichthys flesus), using the amount of yolk protein vitellogenin in the blood of free-living male fish as an indicator of exposure to estrogens. Exposure to the synthetic estrogen ethynylestradiol for 3 weeks confirmed that the vitellogenin response was made and showed that this species is about one order of magnitude less sensitive than the freshwater species rainbow trout. The fish did not respond to the estrogen mimic nonylphenol at concentrations of 30 g/L. Wild male flounder were sampled from four contaminated United Kingdom 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 estuary (Alde River). Vitellogenin concentrations in the Tyne and Mersey fish were four and six 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.

Evidence for estrogenic endocrine disruption in an offshore flatfish, the dab (Limanda limanda L.)

“…This demonstrated elevated concentrations of the female egg-yolk protein precursor vitellogenin (VTG) in the blood plasma of caged male trout (Oncorhynchus mykiss) that were placed in UK rivers -especially near sewage treatment works (Purdom, Hardiman, Bye, Eno, Tyler, & Sumpter, 1994). The finding was extended by Cefas to male flounders (Platichthys flesus) in UK estuaries in the 1990s (Allen, Matthiessen, Scott, Haworth, Feist, & Thain, 1999a;Allen, Scott, Matthiessen, Haworth, Thain, & Feist, 1999b) and to cod (Gadus morhua) in the open sea within the last five years (Scott, Katsiadaki, Witthames, Hylland, Davies, McIntosh et al, 2006b). …”

Partitioning, bioavailability and effects of oestrogens and xeno-oestrogens in the aquatic environment

“…High levels of VTG (up to 20 mg ml -1 plasma) have also been measured in male flounder from other heavily industrialized British estuaries. In contrast, levels of VTG were low or undetectable in male flounder from estuaries draining rural areas, or from urban areas with relatively little heavy industrial activity Allen et al, 1999aAllen et al, , 1999b.…”

The occurrence, causes, and consequences of estrogens in the aquatic environment

“…In particular, Purdom et al [1] had shown that one of the steroid estrogens, the pharmaceutical ethinyl estradiol (EE2), was extraordinarily active in fish: very low to sub-ng/L concentrations induced vitellogenin synthesis in a concentration-dependent manner. Perhaps of even greater surprise, some estuaries proved to be estrogenic [6], although the causative chemicals were not identified at the time and have not been since.…”

“…It would be difficult to think of a more environmentally relevant parameter than reproduction when attempting 2084 All Supplemental Data may be found in the online version of this article. See Table S1 for the number of citations and rank of all the ''Top 100'' papers, which in this essay are references [3][4][5][6][7][9][10][11][12][13][14][15]19,20].…”