Journal of Environmental Engineering Technology•2026•DOI: 10.13205/j.hjgc.202606014
Microplastics, as emerging environmental pollutants, can adsorb psychotropic drugs in aquatic environments, facilitating their migration and transformation, ultimately posing ecological risks. This study investigated the adsorption behavior and mechanisms of four common microplastics—polyethylene (PE), polypropylene (PP), polystyrene (PS), and polyvinyl chloride (PVC)—each with a particle size of 50 μm, toward three psychoactive drugs: diazepam, fluoxetine, and mianserin. Adsorption kinetics, isotherms, and the effects of pH and salinity were examined. Kinetic data fitted well to a pseudo-second-order model, indicating chemisorption as the rate-limiting step. Isotherm analysis using Langmuir and Freundlich models revealed that PE exhibited the highest affinity for fluoxetine, PP for mianserin, and PVC for diazepam, while PS showed linear adsorption for fluoxetine, suggesting partitioning. The adsorption of diazepam was maximal at pH 6.5–8.5, typical of natural surface waters, and increased with NaCl concentration, indicating that non-electrostatic interactions dominate and that higher ionic strength enhances adsorption. Mechanistic insights suggest that hydrophobic interactions, hydrogen bonding, π-π interactions (for PS), and halogen bonding (for fluoxetine) contribute to adsorption. These findings highlight the potential of microplastics to act as vectors for psychoactive drugs, necessitating further research on their environmental fate and ecological implications.
Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202511003
Tailings dam leakage can cause secondary sudden water pollution events, imposing severe combined stress of high turbidity and heavy metal contamination on natural water bodies within a short period, threatening aquatic ecological security. Existing studies have systematically revealed the pollution characteristics and biological effects of such events, which are fundamentally distinct from natural high-turbidity water and industrial wastewater leakage. Compared with natural high-turbidity water, tailings leakage inputs finer particles with higher specific surface area, leading to more intense and prolonged turbidity stress. Meanwhile, heavy metals in tailings are more enriched than natural sediments, with higher proportions of active forms and bioavailability, causing significant bioaccumulation and toxic effects, and long-term decline in benthic community species richness. Compared with industrial wastewater leakage, tailings leakage simultaneously releases high concentrations of fine suspended solids and multiple heavy metals, forming a unique 'physical-chemical' combined stress. This synergistic effect amplifies biological toxicity through multiple pathways such as mechanical damage, light limitation, and oxidative stress, resulting in severe and often irreversible ecological damage, such as impaired fish swimming behavior and collapse of benthic community structure. Analyzing the long-term impacts of tailings leakage on aquatic ecosystems from the perspective of combined stress is helpful for providing scientific basis for emergency response and medium-to-long-term ecological risk prevention of related sudden water pollution events.