The amounts of wastewaters produced around the world are vast. For example, in Finland approximately 100 000 cubic meters of urban wastewater effluents per inhabitant are discharged each year. A recent study in Finland confirmed that Finnish wastewater treatment plants are efficient in removing components that might cause acute effects in whole organisms. However, indications of estrogenic and genotoxic potential were detected in effluents discharged from these treatment plants. Thus, treated wastewater effluents still may cause harmful effects on the environment.
In the long run, compounds that are hormonally active or affect the genome may alter, for example, fish populations in the receiving waters. Indeed, it has already been noticed that estrogenic compounds from wastewater effluents have caused feminization of male fish in the nature.
Estrogenic activity in Finnish municipal wastewater effluents, Water Research, Volume 88, , Pages 740–749, 1 January 2016.
Effluents from wastewater treatment plants (WWTPs) are a major source of estrogenic compounds to the aquatic environment. In the present work, estrogenic activities of effluents from eight municipal WWTPs in Finland were studied. The main objectives of the study were to quantify the concentrations of selected estrogenic compounds, to evaluate their contribution to estrogenic potency and to test the feasibility of the commercial bioassays for wastewater analysis. The effluent samples were analyzed by two in vitro tests, i.e. ERα-CALUX(®) and ELISA-E2, and by liquid chromatography mass spectrometry for six estrogenic compounds: estrone (E1), 17β-estradiol (E2), estriol (E3), 17α-ethinylestradiol (EE2), 17α-estradiol and bisphenol A (BPA). Estrogenic effects were found in all of the effluent samples with both of the bioassays. The concentrations measured with ELISA-E2 (8.6-61.6 ng/L) were clearly higher but exhibited a similar pattern than those with chemical analysis (E2 < limit of quantification – 6.8 ng/L) and ERα-CALUX® (0.8–29.7 ng E2 EEQ/L). Due to the concentrations under limit of quantification, the evaluation of the chemical contribution to estrogenic potency was possible only for E1 and BPA, which contributed less than 10% to the observed effects, except in one sample with a high BPA contribution (17%). The contribution of E2 was significant in two samples where it was detected (28% and 67%). The results demonstrated that more comprehensive information on potential estrogenic activity of wastewater effluents can be achieved by using in vitro biotests in addition to chemical analysis and their use would be beneficial in monitoring and screening purposes.