Do high levels of PPCPs in landfill leachates influence the water environment in the vicinity of landfills? A case study of the largest landfill in China.

Landfill leachates are identified as a significant source of pharmaceutical and personal care products (PPCPs), which might pose a threat to groundwater and surface water nearby the landfill. However, knowledge of PPCP contamination in the surrounding water environment of landfills is very limited. Here we investigated eighteen PPCPs in water environment near the largest landfill in China, focusing on their occurrences and spatial distribution, as well as the environmental risks. The results showed the concentration of target PPCPs was below the limit of quantification (<LOQ) to 53.6 ng/L in the adjacent groundwater samples, decreasing with the distance of sampling sites from landfill. The composition pattern of PPCPs in the groundwater was similar to that in raw landfill leachate. These observations indicated a considerable impact of raw landfill leachates on PPCP contamination in the nearby groundwater. In surface water samples, the occurrence of PPCPs was not consistent with that in raw or treated landfill leachates, but similar to that in the same watershed far away from landfill. Spatially, no obvious difference in the PPCPs concentrations was observed, indicating negligible contribution of landfill on PPCPs in surrounding surface water. The findings allowed the first insights into the impacts of well-constructed and managed landfills on PPCP contamination in the surrounding water environment.