Multi-phase distribution and risk assessment of endocrine disrupting chemicals in the surface water of the Shaying River, -Huai River Basin, China

Herein we investigated the multi-phase distribution and estrogenic effects of endocrine disrupting chemicals (EDCs) in suspended particulate matter (SPM), colloids, and soluble phases from the Shaying River to assess the composition of estrogenic compounds and associated estrogenic risk. The yeast two hybrid (YES) method, cross flow ultrafiltration (CFUF), and LC-MS/MS were employed. Risk quotient (RQ) values ranged from 0.72 to 3.88, revealing that the Shaying River posed high estrogenic risk to aquatic organisms. The contribution ratios of the target EDCs to the EEQ(YES) ranged from 62.7% to 92.5%, indicating that these chemicals were major contributors of estrogenic effects in the Shaying River. Further, 54.0-77.8% of the detected EDCs were distributed in the soluble phase, 15.1-31.7% were bound to colloidal substances, and 3.90-19.4% EDCs were associated with SPM. Significant correlation between total EDC abundance and COD contents was detected, and the concentrations of endogenous estrogens (E1, E2, and E3) were positively correlated with total nitrogen (TN) and total phosphorus (TP). In addition, the in-situ SPM-soluble (Kpoc) and colloid-soluble partition (Kcoc) coefficients were calculated. The log Kpoc values of target compounds varied from 4.10 to 5.19, while log Kcoc values ranged from 4.25 to 5.56. Their Kcoc values were larger than the Kpoc values, indicating that organic colloids were the most important carriers of EDCs in the aquatic environment.