| "In order to improve the treatment efficiency of estrogens in wastewater treatment plants (WWTPs), elucidation of fate of the estrogen and estrogenic compounds are necessary. In this study,clarification of the fates of estrogen, estrogen sulfates, estrogenic compounds (artificial estrogen and nonylphenol and its relatives) and estrogenic activity by instrumental analysis and estrogenic activity by in vitro assay was carried out in a WWTP. The surveys were conducted in winter and summer season. From the results, decline of removal efficiencies for nitrogen and estrogens in the WWTP were observed in winter. The concentration of estrone increased along the treatment process. Moreover, it seemed that estrone and estrogenic activity circulated between biological reaction tank and final sedimentation tank with activated sludge, while those were rarely removed by biological treatment in summer. The comparison between estrogenic activity detected by the assay and theoretical activity calculated from the results of instrumental analysis suggested that E1and E2 were the chemicals predominantly contributing to the estrogenic activity in the samples." |
