Characteristics of PPCPs pollution and ecological risk assessment in the Ningxia section mainstream of the Yellow river

Pharmaceuticals and personal care products (PPCPs) are a collective term for various emerging pollutants that pose potential risks to the ecological environment and human health. To investigate the pollution characteristics and ecological risks of PPCPs in rivers, this study continuously monitored 55 target PPCPs in the mainstream water of the Ningxia section of the Yellow River from April to September 2023. The results showed that a total of 17 PPCPs (34.55-248.08 ng/L) in 5 classes were detected in the Ningxia Section of the Yellow River, including sulfonamides, quinolones, macrolides, amino alcohols and other drugs. The main antibiotics detected were sulfonamides (10.34±6.04 ng/L). Other drugs were mainly caffeine (CAF, 74.84±40.42 ng/L). The average concentration of PPCPs decreased first, then increased and decreased from upstream to downstream. The average concentration of PPCPs in April was significantly higher than in other months (159.27±52.17 ng/L). The ecological risk assessment results showed that the PPCPs in the Ningxia section of the Yellow River showed low ecological risk. There were significant time differences in the ecological risk levels of major pollutants. CAF is the main component of PPCPs and the main contributor of RQ_sum (62.14%-76.05%) in the water environment of Ningxia mainstream of the Yellow River. In the future, the monitoring, management and early warning of PPCPs in the Yellow River should focus on the CAF concentration and its source.