Biodegradation of bisphenol A in the aquatic environment

Biodegradation potential of bisphenol A (BPA) in the aquatic environments w as investigated using 3 activated sludge and 44 river water microcosms. The biodegradation potential was exhibited by most of the tested microcosms; 3 activated sludge and 40 river water microcosms. However, only 8 river wate r microcosms could completely mineralize BPA, and the others showed accumul ation of common metabolites which were detected as 2 peaks according to a h igh-pressure liquid chromatograph. In total 19 BPA-degrading bacteria were isolated from activated sludge and river water samples, and their BPA degra dation property was also investigated. Although all the BPA-degrading bacte ria could grow on BPA and remove about 70-80% of TOC derived from BPA, they accumulated 2 common metabolites, and they could not be removed by the pro longed cultivation up to more than 1 month. These 2 metabolites were identi fied as 2,3-bis(4-hydroxyphenyl)-1,1-propanediol and p-hydroxyphenacyl alco hol in the culture of a typical BPA-degrading bacterium. The experimental r esults suggested that BPA-degrading bacteria ubiquitously exist in the aqua tic environments, but that they cannot completely degrade BPA, leading to t he accumulation of more recalcitrant metabolites. For complete BPA degradat ion, the presence of microbes which can degrade the metabolites seems neces sary together with SPA-degrading bacteria.