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(T/FF225) A multi-generation study of the effects of Bisphenol A on the fathead minnow (Pimephales promelas). Sohoni, P.1, Tyler, C.2, Hurd, K.3, Caunter, J.3, Hetheridge, M.3, Williams, T.3, Evans, M.3, Toy, R.4, Friederich, U.5, Sumpter, J.1, 1 2 3 4 5 ABSTRACT- To investigate the possible effects of long-term exposure to Bisphenol A (BPA), a multi-generation study was conducted, in which 3 generations of the fathead minnow were exposed to water concentrations of BPA covering the range 1 - 1280 micrograms/litre. Exposure to BPA began when the F0 generation fish were sub-adults, and the experiment lasted a total of 431 days, so that the F1 generation fish were exposed for all of their lives, and the F2 generation fish until 60 days post-hatch. The two highest concentrations of BPA (640 and 1280 micrograms/litre) inhibited growth of both the F0 and F1 generations. Vitellogenin concentrations, which are indicative of exposure to an oestrogenic chemical, were markedly elevated in males exposed to concentrations of BPA at and above 160 micrograms/litre. Female fish, which had much higher vitellogenin concentrations initially, showed much less of a response to BPA. Gonadal growth was inhibited in both sexes by the two highest concentrations of BPA. The most sensitive parameter affected by BPA was spermatogenesis, which was inhibited at concentrations at and above 16 micro-grams/litre. However, reproductive output, assessed by measuring egg production and hatchability, was affected only at the two highest concentrations of BPA. Essentially the same effects occurred in both the F0 and F1 generations. However, the F1 generation appreared somewhat more sensitive (lower concentrations produced significant effects), but this comparison was complicated by the fact that the FO generation fish were exposed to BPA for only the second half of their lives, whereas the F1 generation fish were exposed throughout their entire lives. The results demonstrate that BPA acts as a weak oestrogen to fish when administered via the water, with effects on breeding at and above a concentration of 640 micro-grams/litre. Key words: Bisphenol A, long-term effects, fish, multi-generation test |
