National evaluations of pharmaceutical and personal care products in Chinese landfill leachate: non-negligible socio-economic and rainfall status

Abstract

Pharmaceuticals and personal care products (PPCPs) have received widespread attention owing to their negative effects on the health of ecosystems. While numerous studies monitored the usage of PPCPs, and ignored the systematical investigation of the discarded PPCPs. Here, we collected leachate from 73 landfills across China and detected 52 target PPCPs. A total of 42 PPCPs were detected in 73 landfills in China with a concentration distribution of 10⁻³–10³ μg/L, of which 93 % of the PPCPs had mean concentrations higher than the safe concentrations for antimicrobial resistance selection. The mean concentrations of the top three PPCPs were caffeine (CF), lincomycin (LIN), and acetaminophen (ACET). Gross domestic product, population density, and precipitation were the most dominant factors affecting CF, LIN, and ACET in leachate, whose concentrations remarkably decreased with landfill age. In contrast, the concentrations of hydrophobic PPCPs such as ketoprofen, carbamazepine, diclofenac, sulfadimidine, and erythromycin, were significantly higher in old leachate. Precipitation, hydrophilicity, and pH were the most important factors affecting the occurrence of the hydrophobic PPCPs in leachate. High concentrations of PPCPs in landfill leachate were also detected in economically or densely populated countries worldwide. For the first time, it was found that the concentration of hydrophobic PPCPs increased in old leachate, in contrast to the traditional understanding of decreasing the concentration of PPCPs owing to the biodegradation during landfill.