Occurrence and Estrogenic Potency of Bisphenol Analogs in Sewage Sludge from Wastewater Treatment Plants in Central China.

Land application is suggested to be the most economical sludge disposal method but is also a potential source of bisphenol analogs (BPs) to the environment. In this study, BP concentrations in sewage sludge from Henan province ranged from 15.1 to 2237 ng g-1 dw. BPA was dominant with mean concentration of 140 ng g-1 dw, followed by BPS (mean 43.4 ng g-1 dw), BPF (mean 7.98 ng g-1 dw), BPAF (mean 1.04 ng g-1 dw), BPAP (mean 0.88 ng g-1 dw), BPB (mean 0.38 ng g-1 dw), and BPZ (mean 0.33 ng g-1 dw). Apart from BPB, no significant correlations were found between BPs and wastewater treatment plants characteristics, probably because adsorption does not play a major role in the removal of BPs. The estimated total emission flux of BPs from sludge-amended soils are approximately 62.7 kg year-1. BPA is the largest contributor with emission flux of 45.3 kg year-1. Hazard quotient values for BPs in sludge-amended soils are 3-6 orders of magnitude lower than 1 with total 17β-estradiol equivalents ranging from 0.33 to 26.8 pg g-1 E2EQ dw. Overall, although being partially replaced by other analogs, BPA is still widely used in Henan province.