To investigate the spatial and temporal distribution characteristics and assess the ecological risks associated with emerging contaminants (ECs) in the Beijiang drinking water source, non-targeted screening was conducted using the ultra-high performance liquid chromatography-mass spectrometry technique (UPLC-MS) for one year (June 2022 to May 2023). This study also involved the quantitative detection of eight typical ECs. The results showed that through the non-targeted screening, a total of 346 pollutants were identified, with industrial materials, pharmaceuticals, and pesticides being the predominant pollutants, collectively accounting for 88.2%. Concentrations of eight representative ECs ranged from n.d (undetected) to 180 ng·L-1, with detection rates exceeding 80% for six of them. Notably, higher concentrations were found in endocrine disruptors such as bisphenol A (BPA) and 4-nonylphenol (4-NP), along with the pesticides atrazine (ATZ) and propisochlor (PPS), with median concentrations ranging from 8.12 to 35.58 ng·L-1. The concentrations of ATZ, PPS, roxithromycin (ROX), and ibuprofen (IBU) were significantly higher in the spring season compared to those in other seasons (P<0.05). Elevated ecological risk levels (RQ>1) were observed at sampling point 1 (S1) and sampling point 3 (S3) for ATZ and Lomefloxacin (LOM), while for 4-NP, it was determined to be high only at sampling site 2 (S2). Given their high detection rates and ecotoxicity, particular attention should be paid to ATZ and 4-NP. The concentration level of ATZ exhibited significant seasonal variation due to its agricultural origin, so it is recommended to strengthen control during spring. Overall, this research provides critical insights into a comprehensive understanding of the presence and impact of ECs in this specific region.
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