Spatial distribution and comprehensive evaluation of emerging organic pollutants in effluents from wastewater treatment plants in northern cities of China

This study investigated the occurrence of 42 pharmaceuticals and personal care products (PPCPs), 4 steroid estrogens and 15 phthalates in the effluents of 12 wastewater treatment plants (WWTPs) in 11 northern cities of China. Of the 61 emerging organic pollutants (EOPs), 49 EOPs were detected, and the detection frequencies of 18 compounds were over 90%. PPCPs were the predominant species and contributed to approximately half of the total EOP concentrations in the most of the investigated WWTPs. The four EOPs with the highest mean concentrations of the 49 were metoprolol (798.0 ng L-1), carbamazepine (597.5 ng L-1), sulpiride (543.5 ng L-1) and dimethyl phthalate (502.6 ng L-1). The levels of some detected EOPs showed positive correlations with the total nitrogen level. In the ecological risk evaluation, roxithromycin, diclofenac acid, sulfamethoxazole, ofloxacin, clindamycin, sulpiride, ibuprofen, 17 alpha-ethynylestradiol, and dimethyl phthalate exhibited high or medium risks in the effluents. Four representative compounds, diclofenac acid, roxithromycin, sulfamethoxazole, and dimethyl phthalate, could be selected as indicators for predicting overall EOP levels.