17α-ethynylestradiol and its two main conjugates in seven municipal wastewater treatment plants: Analytical method, their occurrence, removal and risk evaluation

• Published in: The Science of the total environment 2022-03, Vol.812, p.152489-152489, Article 152489
• Main Authors: Wan, Yi-ping, Chai, Bing-wen, Wei, Qiang, Hayat, Waseem, Dang, Zhi, Liu, Ze-hua
• Format: Article
• Language: English
• Subjects: Analytical method; EE2 conjugates; Estrogenic effects; Estrogens; Ethinyl Estradiol - analysis; Municipal wastewater; Removal; Waste Disposal, Fluid; Waste Water - analysis; Water Pollutants, Chemical - analysis; Water Purification
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2021.152489

This work shows the existence of both 17-ethinylestradiol-3-sulfate (EE2-3S) and 17-ethinylestradiol-3-glucuronide (EE2-3G) in seven municipal WWTPs with substantial concentrations (n.d-50.10 ng/L). The calculated removal efficiencies of 17-ethinylestradiol (EE2) in the seven municipal WWTPs ranged from 40.8%–100% with an average removal efficiency of 83.3%. However, upon the inclusion of EE2 concentration transformed from EE2-3S and EE2-3G, the corresponding removal efficiencies were increased to 91.4%–100% with an average removal efficiency of 97.3%. This work is the first to clearly illustrate that EE2 conjugates in raw wastewater could greatly underestimate the removal effectiveness of municipal WWTPs on EE2, indicating the importance of the EE2 conjugates in municipal wastewater having been hardly paid with attention. The EE2-derived estrogen equivalence (EEQ) values in the effluents of seven WWTPs ranged from 0 to 0.98 ng E2/L having an average level of 0.45 ng E2/L, which were relatively low. However, upon the inclusion of EE2 transformable from EE2-3S and EE2-3G in effluents, the EE2-derived EEQ values in effluents would be increased to 0.77–4.85 ng E2/L having an average level of 2.71 ng E2/L, which clearly suggested that ignorance of EE2 conjugates in effluent would largely underestimate EE2's environmental risk to receiving water bodies. Synopsis: The conjugated EE2 has been dominant in municipal wastewater treatment plants (WWTPs) and cannot be ignored. [Display omitted] •EE2 and its two main conjugates were detected in municipal influents and effluents.•EE2-3G rather EE2 was the dominant form in municipal wastewater.•EE2 conjugates greatly affect EE2 removal efficiency in municipal WWTP.•Ignorance of EE2 conjugates in effluent underestimate EE2 environmental risk.