Environmental fish exposure to bisphenol A: what is the level of evidence?

Two years ago, a directive of the European Commission banned the use of baby bottles containing the organic compound bisphenol A (BPA). Nevertheless, BPA is continuously released into the environment from polycarbonate warehouse and is regularly detected in the aquatic environment. Being highly lipophilic, BPA bioaccumulates, a phenomenon that indicates the potential risks posed on the aquatic biota (fish). Toxicological studies demonstrated that at high concentrations (>100-500 μg L-1), BPA is associated with cardiotoxicity and increased mortality, as well as with severe gonadal alterations in fish embryo. Noteworthy, in the environment BPA is usually found in the form of organic micropollutants mixtures, together with other organic toxicants, and therefore additive or synergic effects cannot be excluded. Definition of a cut-off value of BPA concentration in the aquatic environment is still pending and assessment of consequences on fish are based on measurement of global estrogenicity of water samples; preliminary data suggest transcriptomic-based tests will provide evidence for more sensitive and specific assays for BPA effects.