Comparison of steroid hormone concentrations in domestic and hospital wastewater treatment plants

Influent and effluent samples originating from two wastewater treatment plants (WWTPs) (treating hospital wastewater and domestic wastewater, Belgium) have been analyzed in order to estimate their steroid hormone content. The natural estrogens estrone (E1), 17 beta-estradiol (E2), and the synthetic 17 alpha-ethinylestradiol (EE2) together with other steroid hormones progesterone (P) and testosterone (T) metabolites were detected in these samples. The hormone concentrations in both the hospital and the domestic WWTP samples were not significantly different and ranged from 100 ng P/L. E2 was detected once at a concentration of 17 ng/L. In the domestic WWTP which comprises a conventional activated sludge treatment in parallel with a membrane bioreactor, no differences in estrogen removal efficiency could be observed for both treatments. In comparison to chemical analysis data, the Yeast Estrogen Screen (YES) appears to underestimate the influent estrogen concentrations, probably due to influent toxicity for the YES. Effluent estrogen concentrations, on the other hand, were overestimated by the YES test, probably due to the presence of other estrogenic compounds in the effluent