Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are recognized as critical environmental health hazards, however, their toxicity mechanisms in specific organ systems remain poorly characterized. This study systematically investigated the chain length-dependent nephrotoxicity of PFAS and their inhibitory effects on renal carboxylesterase (CES) activity. In vitro experiments revealed that PFAS were cytotoxic to Human Kidney-2 (HK-2) cells in a dose-dependent and chain length-dependent manner. Furthermore, functional group modification significantly affected the toxicity, perfluoroalkyl carboxylic acids (PFCA) showed the strongest toxic effects compared to fluorotelomer alcohols (FTOH) and perfluoroiodides of the same carbon chain length. PFAS inhibited CES activity in a concentration-dependent manner, with stronger inhibitory effects observed at higher concentrations. PFCA showed the strongest inhibition of CES activity and chain length-dependent manner. Molecular simulations indicated that the PFAS easily bind to CES, suggesting PFAS may affect the activity by affecting secondary structure of CES. In vivo experiments revealed that exposure to perfluorocapric acid (PFDA) in C57BL/6 mice significantly suppressed renal CES activity and induced kidney injury, whereas perfluorohexanoic acid (PFHxA) exerted negligible effects. In addition, kidney weight was positively correlated with CES activity, suggesting a potential causal relationship between CES and PFAS-induced nephrotoxicity. Overall, this study not only provides new insights into the toxicological mechanisms of PFAS-laying a scientific foundation for the safety assessment of alternative compounds and the formulation of risk management strategies-but also validates the reliability of in vitro cell-based assays for the early screening of PFAS biotoxicity.

Plastic pollution alters the natural organic carbon pool in aquatic ecosystems via releasing pseudonatural dissolved organic matter (DOM). However, the composition and subsequent ecological effects of DOM leached from differently colored plastics remain unclear. Here, pronounced heterogeneity in the DOM released by colored polyethylene (PE) plastics is revealed: red PE releases higher levels of DOM, whereas white, black, and yellow PE produce more labile DOM. As a result, these labile PE‐derived DOM foster the growth of opportunistic taxa (notably copiotrophs within Pseudomonadota ), reshaping community structure and resistance gene profiles. The elevated abundance of β‐lactamase genes highlights the potential risk of antibiotic resistance dissemination associated with black PE plastic pollution. Correlation‐based network analyses suggest that labile PE‐derived DOM inputs are associated with enhanced metabolic exchange and synergistic reallocation of available resources, accompanied by coordinated shifts in bacterial interactions and antibiotic resistance gene–host linkages. Taken together, the findings emphasize the overlooked role of plastic color in modulating DOM behavior and ecological impacts for the first time, offering targeted insights for mitigating plastic pollution and guiding sustainable production practices.

Studying the interaction between pesticide contamination in the plant system and the dissolved organic matter (DOM) composition is important to understand the impact of pesticides and plants on the ecological function of DOM. The present study investigated the effects of DOM on the bioaccumulation and biotransformation of carbamates in plants, carbamate exposure on DOM composition, and plant root secretion on the interaction between DOM and carbamates. The concentrations of carbamates and their metabolites in living cabbage plants were continuously tracked through an in vivo analytical method. The presence of DOM was found to reduce the highest bioconcentrations and shorten the time it took to reach the highest bioaccumulated amounts of isoprocarb and carbofuran in plants, while it showed no significant effect on the uptake behavior of carbaryl. DOM profiling results indicated that carbamate exposure substantially decreased the number and molecular diversity of DOM. Notably, plant root secretion alleviated carbamate-induced DOM molecular alterations by inducing a higher turnover rate of DOM compared to that in the uncontaminated group, highlighting the role of plants in mitigating the effects of exogenous pesticide exposure on DOM composition and maintaining DOM molecular homeostasis.