Analysis of the Toxic Effects of Bisphenol A on the Groups of Vertebrate Animals: a Comprehensive Review of Research 2015-2021

The toxic effects of Bisphenol A (BPA) have been studied in individual experimental animals under different conditions. However, without a systematic approach, it is difficult to compare and analyse the results because of differences in doses (concentration), dosing periods (exposure), research methods, and the effects of BPA. We systematically compared and analysed recent research (between 2015 and 2021) that examined the effects of BPA on individual experimental vertebrates (fishes, amphibians, birds, and mammals). We divided the experiments into two categories: experiments on fish and amphibians by indirect administration, and experiments on birds and mammals by direct administration. The deleterious effects of exposure to BPA were classified into two types: morphological and anatomical effects, and physiological and neurocognitive effects. Experimental animals that had less weight, were younger, and were farther away from humans in evolutionary relationships, showed toxic effects even if they were exposed to low concentrations of BPA in the short term. Long-term administration of a small amount of BPA and short-term administration of a large amount of BPA also showed severe toxic effects. When the parents absorbed BPA during puberty, just before fertilisation, or during pregnancy, toxic effects were transmitted from dosed parents to offspring. With increasing amounts of BPA production and waste, there is a growing possibility that animals in various ecosystems will be exposed to BPA. Therefore, it is necessary to identify the harmful effects of BPA on various animals and the conditions under which it affects them. We hope that the results reported here will contribute to the development of standardized study designs for BPA research, to ensure that results can be more readily compared.