Input/output balance of estrogenic active compounds in a major municipal sewage plant in Germany

24 h samples of untreated and treated wastewater were taken in parallel fro m a modern municipal sewage plant in southern Germany in March and June 199 8. After solid phase extraction, total estrogenic activity was quantitative ly measured with a miniaturized E-screen assay and the levels of nine estro genic phenolic chemicals analyzed by HRGC/LRMS, 17 beta-estradiol equivalen t concentrations (EEQ) were 58 and 70 ng/l in the influent and 6 ng/l in th e effluent, indicating that the load of estrogenic activity of the wastewat er was reduced by about 90% in the sewage plant. Less than 3% of the estrog enic activity was found in the sludge. 4-t-octylphenol, 4-nonylphenol, bisp henol A, 2-hydroxybiphenyl, and 4-chloro-3-methylphenol were detected in th e untreated wastewater at levels from 0.13 to 3.6 mu g/l. 4-t-octylphenol, dr-nonylphenol, and bisphenol A were present in the effluent at concentrati ons from 0.16 to 0.36 mu g/l, 2-hydroxybiphenyl and 4-chloro-3-methylphenol were not detectable. The contribution of the quantified levels of phenolic xenoestrogens to total estrogenic activity in the sewage was 0.7-4.3%. (C) 2000 Elsevier Science Ltd. All rights reserved.