Goethe University Frankfurt am Main , Department Aquatic Ecotoxicology, Max-von-Laue-Str. 13, 60438 Frankfurt, Germany.
Federal Institute of Hydrology , Am Mainzer Tor 1, D-56068 Koblenz, Germany.
Environ Sci Technol. 2016 Oct 4;50(19):10606-10615. doi: 10.1021/acs.est.5b05732. Epub 2016 Feb 24.
Conventional activated sludge treatment of wastewater does not completely remove micropollutants. Here, extending anaerobic conditions may enhance biodegradation. To explore this, we combined iron-reducing or substrate-limiting and aerobic pilot-scale reactors directly at a wastewater treatment plant. To assess the removal of endocrine disrupting chemicals (EDCs) as group of micropollutants that adversely affects wildlife, we applied a bioanalytical approach. We used in vitro bioassays covering seven receptor-mediated mechanisms of action, including (anti)androgenicity, (anti)estrogenicity, retinoid-like, and dioxin-like activity. Untreated wastewater induced antiandrogenic, estrogenic, antiestrogenic, and retinoid-like activity. Full-scale as well as reactor-scale activated sludge treatment effectively removes the observed effects. Nevertheless, high antiandrogenic and minor dioxin-like and estrogenic effects persisted in the treated effluent that may still be environmentally relevant. The anaerobic post-treatment under substrate-limiting conditions resulted in an additional removal of endocrine activities by 17-40%. The anaerobic pre-treatment under iron-reducing conditions significantly enhanced the removal of the residual effects by 40-75%. In conclusion, this study demonstrates that a further optimization of biological wastewater treatment is possible. Here, implementing iron-reducing anaerobic conditions preceding aerobic treatment appears promising to improve the removal of receptor-mediated toxicity.
传统的活性污泥法处理废水不能完全去除微量污染物。在这里，延长厌氧条件可能会增强生物降解。为了探索这一点，我们在污水处理厂直接将铁还原或基质限制与好氧中试规模反应器相结合。为了评估内分泌干扰化学物质（EDCs）的去除情况，我们采用了一种生物分析方法。我们使用了涵盖七种受体介导作用机制的体外生物测定法，包括（抗）雄激素、（抗）雌激素、类视黄醇和二恶英样活性。未经处理的废水诱导了抗雄激素、雌激素、抗雌激素和类视黄醇样活性。全规模和反应器规模的活性污泥处理有效地去除了观察到的效果。然而，在处理后的废水中仍存在高抗雄激素和少量二恶英样和雌激素样作用，这可能仍然具有环境相关性。在基质限制条件下进行的厌氧后处理可使内分泌活性再去除 17-40%。在铁还原条件下进行的厌氧预处理可使残留效应的去除率提高 40-75%。总之，本研究表明，生物废水处理的进一步优化是可能的。在这里，在好氧处理之前实施铁还原厌氧条件似乎有望改善受体介导毒性的去除。
