Quantification of phytoestrogens in industrial waste streams

Chemical compounds, including plant-based phytoestrogens, can function as hormone mimics and alter endocrine signaling in wildlife. In the present study, the waste streams from 19 plant-processing industries, including biofuel manufacturers, were sampled and analyzed for the phytoestrogens genistein, daidzein, coumestrol, formononetin, biochanin A, and zearalenone, via liquid chromatography/mass spectrometry. Eight of these industries contained phytoestrogens at environmentally relevant levels (≥1,000 ng/L), with the highest at approximately 250,000 ng/L. The influent and effluent streams of three municipal wastewater treatment plants receiving flow from some of these industries also were sampled and analyzed for the same phytoestrogens. It appeared that aerobic biological treatment, such as activated sludge, was able to remove these compounds from the liquid stream. Nevertheless, the effluent stream from one of the wastewater treatment plants had a phytoestrogen concentration above 1,000 ng/L. Results of the present study indicate the need for caution when designing facilities to treat the effluents from biofuel and other plant-processing industries.