Zunyao Wang

Microplastics (MPs) are increasingly recognized as vectors for organic additives in soil, yet the photochemical fate of additive-loaded MPs remains poorly understood. This study quantitatively defines, for the first time, the effective photodegradation depth of organic additives in a plastic–soil composite. Using butylated hydroxytoluene (BHT) and tetrabromobisphenol A (TBBPA) as model additives and polyvinyl chloride (PVC) as a representative MP, we demonstrate that PVC-bound additives exhibit substantially shallower effective photodegradation depth (approximately 3.98 mm) compared to additives directly sorbed onto soil particles (by 0.66–1.33 mm). This ”umbrella” effect is attributed to three synergistic mechanisms: light shielding by plastic fragments, spatial isolation of additives from soil photosensitizers, and suppression of hydroxyl radical (·OH) generation by PVC. LC–MS analysis identified 19 transformation products. DFT calculations confirmed that ·OH attack has lower energy barriers than Cl· attack, consistent with the predominance of hydroxylated products. Toxicity predictions revealed that most intermediates exhibit higher developmental toxicity and bioaccumulation potential than their parent compounds. Collectively, these findings reveal that MPs act as a photochemical ”umbrella” for organic additives, prolonging their persistence in surface soil and posing potential ecological risks. This study provides a mechanistic basis for risk assessment of additive-containing MPs in terrestrial ecosystems.

As legislative regulations on traditional plasticizers have been tightened globally, diisononyl cyclohexane-1,2-dicarboxylate (DINCH) gains widespread use owing to its environmental safety claims. Nevertheless, the emerging toxicological evidence raises concerns about its health and ecological risks. In soil earthworms, the dynamic bioaccumulation, biotransformation, and tissue-specific distribution of DINCH were first characterized using mass spectrometry imaging, and the major metabolites of monoisononyl cyclohexane-1,2-dicarboxylate (MINCH) and hydroxylated derivatives were primarily distributed in the earthworm coelom. Noticeably, the multilevel toxicological responses including growth inhibition, tissue damage, and oxidative stress were shown with a cascade of physiological and biochemical perturbations, particularly in endocrine and metabolic homeostasis. Disruption of peroxisome proliferator-activated receptor (PPARγ) signaling with downstream lipid biosynthesis and endocrine-metabolic homeostasis was further confirmed via integration of transcriptomics and metabolomics, while PPARγ was prioritized as a candidate biomarker for apparent exposure. Due to the stronger binding interactions of MINCH by in vitro/in silico studies, a metabolite-mediated mechanism whereby MINCH may mimic endogenous fatty acid-like ligands to regulate PPARγ was rationalized for lipid metabolism and endocrine disturbances. These findings provide early warnings of the ecological relevance and potential risks of DINCH to soil ecosystems and underscore the essentiality of incorporating bioactive metabolites into full environmental risk assessments.

Per- and polyfluoroalkyl substances (PFAS) represent a global environmental threat due to their chemical stability and bioaccumulation. However, the efficacy of current adsorbents in contaminated source remediation is constrained by limited selectivity and the lack of sustainable regenerability. Here we report AR-1, a pore-size-tuned cross-linked polymethacrylate adsorbent for perfluorooctanoic acid (PFOA) capture and water-mediated regeneration. By engineering high-density ester-functionalized amphiphilic microenvironments within nanoconfined channels, AR-1 relies on engineered mesoporous confinement, hydrogen bonding, local polar contacts, and hydrophobic/fluorocarbon-chain partitioning interactions. These interactions enable selective molecular recognition of PFOA and promote its confined self-assembly into stable intrapore aggregates. Consequently, AR-1 yields a PFOA adsorption capacity of 531.8 mg g–1 and a removal efficiency of >99% in industrial wastewater. It maintains high selectivity for PFOA even in the presence of a 10,000-fold excess of competing background ions. Furthermore, pH-responsive modulation of interfacial binding affinity allows for nearly 100% regeneration using water alone. This strategy offers a sustainable, high-performance solution to the critical challenge of PFAS contamination.

Microplastics (MPs) are pervasive vectors in soil, but their quantitative role in additive transport and transformation remains unclear. This study examines the release, transport, and transformation of TBBPA and BDE-209 from polystyrene MPs. Vertical MP migration forms an observed secondary emission front under hotspot-like conditions at 5–7 cm depth, which influences the spatial distribution of the strongly hydrophobic BDE-209, leading to a concentration plateau at this interface. We developed a mechanistic model based on Fick’s second law, parameterized with the first-order release rate constant (krelease), colloidal diffusion coefficient (Dsc), and biodegradation rate constant (k) under our experimental conditions. This model successfully captured the distinct migration patterns of the two additives, supported by machine learning (XGB) validation within the scope. Depth and time were the primary experimental controls, while EC and pH were the key soil properties influencing additive fate. Beyond transport, MP-driven soil changes promoted extensive additive transformation into 59 byproducts. The majority of BDE-209 transformation products were predicted to exhibit significant oral toxicity and high persistence in the environment. Our findings propose a novel, comprehensive framework that advances beyond existing approaches by linking MP-mediated transport to hazardous product formation, providing essential insights for the risk assessment of plastic-contaminated soils.

Phenolic pollutants are toxic and widespread, making their removal an urgent priority. Metal-modified biochar (MBC) shows great potential for non-radical activation of persulfate (PS), enabling efficient and low-carbon removal of phenolic pollutants. However, regulating the non-radical mechanism remains challenging due to the lack of systematic understanding of how metal-modification-related preparation parameters influence the reaction pathway. Herein, a machine learning (ML) framework focusing on metal modification parameters was introduced. Five ML algorithms were used to build binary classification models. XGBoost achieved the best performance, with an area under the receiver operating characteristic curve (AUC) of 0.711 on the independent test set and both precision and recall of 0.733 for identifying the non-radical-dominated mechanism. SHapley Additive exPlanations (SHAP) and partial dependence analysis reveal that high temperatures (>800 °C) and moderate heat treatment time (1.7–2.5 h) favor non-radical pathways, with Cu introduction and multi-metal synergy serving as key regulatory factors. Based on SHAP dependency analysis and metal combination statistics, two strategies for the targeted design of non-radical-dominated systems are proposed: (1) prepare Cu-modified biochar at 900 °C; (2) prepare Cu-Fe bimetallic-modified biochar at 600 °C. This work provides a data-driven theoretical framework and operational strategies for targeted regulation of the non-radical mechanism in the MBC/PS system, opening new avenues for the efficient and low-carbon treatment of phenol-containing wastewater.

The widespread application of ionic liquids (ILs) as solvents and functional materials raises growing concerns about their environmental persistence and potential toxicity. This study demonstrates the efficient degradation (>96.2% in 20 min) of alkylimidazolium IL, 1-pentyl-3-methylimidazolium by the UV/NaClO process, which remains applicable across a broad pH range and in various real water matrices. By coupling feature-based molecular networking with in silico toxicological assessments, we identified transformation products (TPs) and uncovered potential toxicity risks correlated with structural evolution. Molecular docking showed that dealkylation and hydroxylation attenuate binding affinities with human serum albumin (HSA) and human acetylcholinesterase through diminished hydrophobic contacts. Subsequent molecular dynamics simulations explored the dynamic and thermodynamic behaviors of representative TPs, revealing potential impairment of HSA's transport function and pseudoenzymatic activities triggered by ring-opening. Particular attention is warranted regarding structural risks associated with cleavage at the C(4)═ C(5) bond of the imidazole heterocycle. This work first establishes an analytical-computational framework for mapping degradation pathways and evaluating TP risks, providing both mechanistic insights and practical guidance for the sustainable treatment of IL-containing wastewater.

The UV filter benzophenone-3 (BP-3) is a prevalent environmental pollutant due to its extensive use in personal care products, raising concerns about its ecological risks. This study investigated the pH-dependent oxidative stress effects of benzophenone-3 (BP-3) on Carassius auratus by measuring four key biomarkers—superoxide dismutase, catalase, glutathione, and malonaldehyde in liver tissue. The results demonstrated that BP-3 exposure led to significant oxidative stress, as evidenced by altered antioxidant levels and increased lipid peroxidation. The integrated biomarker response indicated that stress was more pronounced at higher BP-3 concentrations and varied with pH, being greatest under acidic conditions. These findings demonstrate that the toxicity of BP-3 is strongly influenced by environmental pH, highlighting the necessity of incorporating pH variations into ecological risk assessments of ionizable organic pollutants.

Benzophenone-3 (BP-3), a widely used ultraviolet filter in personal care products, has been extensively detected in aquatic environments and poses potential ecological risks. This study innovatively investigated the pH-dependent acute toxicity of BP-3 to three model aquatic organisms—Daphnia magna, Photobacterium phosphoreum, and Danio rerio—by determining the EC₅₀ and LC₅₀ values across a pH range of 5.0 to 9.0. Our results revealed that BP-3 exerted greater acute toxicity on all three tested aquatic organisms under acidic conditions (pH 5.0) than under alkaline conditions (pH 9.0). The increased toxicity with lower pH was attributed to the predominance of the more lipophilic molecular form of BP-3, emphasizing the significant influence of environmental pH on BP-3 toxicity. These findings provide essential toxicological data for assessing the ecological risks of BP-3 in diverse aquatic environments, highlighting the necessity of considering BP-3 concentration, environmental pH and exposed species in ecological risk assessments.