Ying Zhang, Nemin Luo, Decai Zhang, Bin Yan, Jianhui Huang, Haolong Zhang, Caifeng Lin, Mingyuan Lin, Shuai Yang, Yan Lin
Landfill leachate is an important secondary source of plasticizers; however, field-based evidence on their occurrence and full-scale treatment performance remains limited, particularly across different regions and treatment systems. In this study, raw leachate, disc-tube reverse osmosis (DTRO) permeate, and resin-polished effluent were collected from 11 landfill sites in 11 Chinese cities to investigate 10 target plasticizers, including bisphenol A (BPA), alkylphenols (APs), and phthalate esters (PAEs). PAEs dominated the concentration burden in raw leachate, ranging from 1.37 to 714.55 μg/L, whereas BPA and APs occurred at lower but widely detectable levels (0.56-3.43 μg/L). Pronounced spatial heterogeneity was observed among cities, suggesting that plasticizer profiles may be influenced by differences in waste-stream characteristics and leachate matrices. Across most sites, DTRO served as the primary removal barrier, achieving > 95 % removal of phenolic compounds, whereas ester removal efficiencies varied considerably (21.97-99.90 %). Meanwhile, the downstream resin unit further reduced membrane-permeable residuals, resulting in lower low-concentration levels across compounds and a more uniform residual distribution in the final effluent. Screening-level ecological risk assessment showed that raw leachate generally exhibited low to high ecological risk, with several PAE species reaching high-risk levels, whereas post-DTRO risk levels declined markedly but residual ecological risks persisted for certain compounds, particularly diisononyl phthalate (DINP) at multiple sites. Overall, this study provides multi-city field evidence on the occurrence patterns, compositional heterogeneity, stage-specific removal behavior, and residual ecological risks of plasticizers in landfill leachate, and highlights the complementary roles of DTRO and resin in full-scale treatment systems.