Occurrence, Spatiotemporal Distribution, Source Apportionment, and Ecological Risk Assessment of PPCPs in the Taipu River, a Strategic Trans-Boundary Water Source in Eastern China

Pharmaceuticals and personal care products (PPCPs) are contaminants of emerging global concern, yet their long-term fate and distribution in strategic trans-boundary water source areas remain underexplored. This study conducted a comprehensive monitoring campaign spanning from 2018 to 2020, with six sampling campaigns carried out in August 2018, December 2018, May 2019, August 2019, December 2019, and May 2020, to investigate the occurrence, spatiotemporal dynamics, source apportionment, and ecological risks of 54 PPCPs in the surface water and sediments of the Taipu River in eastern China. Utilizing non-target screening via liquid chromatography high-resolution mass spectrometry (LC-HRMS), 54 PPCPs across 15 categories were detected, with average total concentrations of 28.60 ng/L in surface water and 13.01 ng/g in sediments. Sulfonamides, quinolones, and non-steroidal anti-inflammatory drugs (NSAIDs) dominated the aqueous phase (with bisphenol A and sulfamethoxazole highly prevalent), while hormones (e.g., estriol) and quinolones (e.g., ciprofloxacin (CIP)) exhibited significant accumulation in the benthic zone. Spatiotemporal analysis revealed a seasonal pattern where PPCP concentrations were higher in the dry season than in the wet season, primarily driven by hydrological dilution and climate-induced degradation. Furthermore, Positive Matrix Factorization (EPA PMF 5.0) extracted five distinct source factors for each matrix. Specifically, surface water pollution was primarily driven by domestic wastewater, municipal effluents, medical discharges, and localized pharmaceutical emissions, whereas sediments acted as a long-term sink predominantly for domestic wastewater, agricultural/veterinary runoff, and municipal/industrial emissions. Ecological risk assessment indicated that while most of the nine high-frequency contaminants posed low risks, specific compounds such as CIP, SM2, and E3 presented medium risks in surface water, whereas ENR, CIP, and SPI posed medium risks in sediments. These findings emphasize that the continuous multi-source input and the resulting pseudo-persistence of PPCPs in sediments warrant prioritized continuous attention and targeted pollution control strategies in the Taipu River Basin.