Environmental Research最新文献

Agricultural activities are a major source of microplastic (MPs) contamination due to the extensive use of plastic materials in mulching films, irrigation systems, and nursery supplies. According to the FAO, agricultural plastic consumption reached approximately 12.5 million tons in 2021, raising concerns about the accumulation of MPs in soils and their transfer to the soil-plant system and food chain. Increasing evidence indicates that MPs can negatively affect plant physiology, impairing germination, root development, nutrient uptake, and redox homeostasis. Among commonly used polymers, polystyrene (PS) is of particular concern due to its documented phytotoxicity. In this study, we investigated the effects of polystyrene microplastics (PS-MPs, 1 μm), supplied through the culture medium, on two Capsicum annuum L. landraces from southern Italy, Sassaniello-giallo (SY) and Papaccella-gialla (PY). Germination performance, seedling growth, mineral uptake, and oxidative responses were evaluated to assess cultivar-specific sensitivity. PS-MPs negatively affected seedling development in both landraces, reducing biomass accumulation, root length, and leaf area, and inducing oxidative stress. Microscopic observations revealed the presence of MPs or their aggregates in the rhizoderm, root cortex, vascular tissues, and near root hairs, with evident damage to the root apex. Differential responses were observed between landraces: SY showed reduced germination in the presence of MPs, whereas PY exhibited a stimulation of germination, possibly linked to differences in antioxidant capacity. Overall, the observed effects suggest that PS-MPs toxicity is largely driven by physical interactions with plant tissues, leading to impaired physiological processes. These findings highlight the need for further research to clarify the mechanisms underlying MPs-plant interactions.

Ofloxacin (OFX) represents a significant threat to aquatic ecosystems and human health due to its environmental persistence, antimicrobial activity, and potential to promote drug resistance. However, how to achieve its efficient and environmentally friendly removal remains a challenge. In this study, a novel Mn₃O₄/NiCo₂S₄ composite catalyst was constructed for the first time via a hydrothermal method to activate peroxymonosulfate (PMS) for the rapid removal of OFX. Under optimal conditions, the NM-2/PMS system achieved 90.5 % removal within 20 min and exhibits excellent catalytic performance and cycling stability across various water matrices, highlighting its promising practical applicability. Quenching experiments, EPR analysis, and reactive species contribution calculations revealed that singlet oxygen (¹O₂) plays a dominant role in PMS activation for OFX degradation, while sulfate radicals (SO₄^·-), hydroxyl radicals (·OH), and superoxide radicals (O₂^·-) contribute synergistically. Mechanistic investigations further demonstrated that redox cycling among Ni²⁺/Ni³⁺, Co²⁺/Co³⁺, and Mn²⁺/Mn³⁺/Mn⁴⁺, in concert with synergistic interactions with sulfur species, collectively promoting the efficient activation of PMS. Moreover, potential OFX degradation pathways were elucidated using ESP mapping, DFT calculations, and LC-MS analysis, with toxicity evaluations performed for the intermediates. Therefore, based on the design concept of high efficiency, environmental friendliness and stability, this study developed a novel heterogeneous catalyst (NM-2), providing a promising strategy for the effective removal of recalcitrant organic pollutants from real water matrices.

Naphthenic acids (NAs) are a class of toxic petroleum-derived carboxylic acids that are being increasingly detected in marine environments at ecologically concerning concentrations. However, the molecular initiating events underlying NA toxicity and the adaptive responses of marine organisms during prolonged exposure remain poorly defined. In this study, juvenile marine medaka (Oryzias melastigma) were exposed to environmentally relevant NA concentrations for up to 28 days. Multi-omics and molecular docking analyses indicated that the NAs interacted with G-protein coupled receptors (GPCRs) in marine medaka, disrupting mTOR and FoxO signaling and enhancing oxidative stress. Antioxidant depletion was associated with mitochondrial damage and apoptosis, leading to dysfunction. Combined with the disturbance of lipid metabolism (glycerophospholipids, ether lipids, and sphingolipids), this disrupted the energy supply and induced abnormal locomotor behavior. Notably, low-level NA exposure initially elicited stimulatory responses, which transitioned to inhibitory effects over time. This temporal shift likely results from the progressive accumulation of oxidative stress, ultimately amplifying the ecological risks associated with prolonged exposure. Overall, this study elucidates a previously uncharacterized receptor-mediated pathway underlying NA toxicity and establishes a quantitative framework for evaluating the long-term ecological risks posed by petrochemical pollutants. These findings provide mechanistic and predictive insights for assessing environmental health risks from chronic low-dose NA exposure in marine ecosystems.

Antibiotics (e.g., ofloxacin) pollution is an emerging environmental concern due to its persistence and potential health risks. Advanced oxidation processes (AOPs) offer promising solutions, yet their practical application is often limited by catalyst cost and stability. Here, we report the use of natural vivianite-a low-cost iron phosphate mineral-as an efficient peroxymonosulphate (PMS) activator for ofloxacin degradation. Under the optimised conditions, 97 % of ofloxacin was effectively degraded within 60 min. The ofloxacin degradation ratio could still reach 76 % after three consecutive cycles. Mechanistic investigations revealed Mn²⁺ and Co²⁺ isomorphic substitutions within the vivianite lattice, which induced electron cloud redistribution and promoted the formation of metal-oxygen-metal and metal-oxygen bonds. These structural changes enhanced charge transfer and facilitated PMS adsorption and activation via both surface-bound sites and leached phosphate species. Electron paramagnetic resonance spectroscopy confirmed that degradation proceeded through synergistic radical (·OH, SO₄·^-, O₂·^-) and non-radical (¹O₂) pathways. Importantly, the degradation products exhibited significantly lower toxicity than ofloxacin itself, underscoring the environmental relevance of this process. These findings highlight the potential of natural vivianite as a cost-effective and sustainable PMS activator for antibiotic removal in water treatment applications.

Benzo[a]pyrene (BaP) is a persistent organic pollutant (POP) that deposits in the soil through industrial and related anthropogenic inputs, and it resists to degrade naturally. Like most POPs, BaP binds strongly to organic matter thus affecting microbial removal owing to its limited bioavailability. This study evaluates BaP removal from soil inoculated with Pheretima guillelmi under freshly spiked and aged contaminated conditions while assessing its impact on soil chemistry, enzyme activities, and microbial community structure. Results revealed that BaP removal rates were 36.96 % and 39.47 % in fresh and aged contaminated soils, respectively, after 60 days of incubation in the presence of earthworms. The residual concentration of BaP as well as its bioaccumulation factor found in earthworm tissue drastically reduced under aged treatments thus revealing reduced or limited bioavailability. The electrical conductivity, ammonium nitrogen (NH₄⁺-N) and nitrate nitrogen (NO₃^--N), available potassium content; catalase and dehydrogenase activities increased due to earthworm burrowing, feeding, and casting activities whereas urease and protease were unaffected under aged conditions. 16S rRNA gene sequencing analysis indicated an increase in bacterial α-diversity accompanied by the enrichment of putative BaP-degrading genera Flavobacterium, Sphingomonas, Aeromonas, Mesobacillus, and Microvirga. Results of functional prediction and co-occurrence network analyses demonstrated that BaP perturbed microbial associations, however earthworm containing treatments maintained higher bacterial association as well as functional resilience. These results validate that P. guillelmi enhances remediation potential in aged BaP-contaminated soils through adjustment of nutrient balance in the soil, stimulation of pollutant-degrading taxa, and strengthening microbial interactions.

Introduction: Per- and polyfluoroalkyl substances (PFAS) are persistent organic pollutants with potential adverse neurobehavioral effects. However, research on the effects of alternative PFAS and PFAS mixture on children's behavior is limited.

Methods: Children from the Taiwan Birth Panel Study II (TBPS II) were enrolled, and their serum was analyzed for 11 types of PFAS. Behavioral performance was assessed using the Conners' Kiddie Continuous Performance Test, 2nd Edition (K-CPT 2). Linear regression and quantile g-computation (QGC) analyses were performed to determine the relationships between PFAS exposure and children's behavioral performance.

Results: A total of 448 children aged between 6 and 7 years were included in the study. PFAS concentrations varied considerably, with perfluorobutanoic acid (PFBA) showing the highest geometric mean (6.538 ng/mL) and PFDoDA the lowest (0.05 ng/mL). Among girls, perfluoropentanoic acid (PFPeA) levels were adversely associated with omissions (adjusted β=3.72, 95% confidence interval= 0.80, 6.63). There is no strong evidence for the joint effect of the PFAS mixture on K-CPT 2 scores. However, negative joint effects on K-CPT 2 indicators for boys and positive joint effects for girls are observed for perfluorobutanesulfonic acid (PFBS)and perfluorohexanoic acid (PFHxA).

Conclusion: This study highlights the modest adverse effects of alternative PFAS on child behavioral performance and the importance of sex differences. Future research should focus on the toxicological characteristics and health risks of short-chain PFAS substitutes.

Abandoned mines cause environmental and health risks worldwide. Mining waste is characterized by acidic pH and high metal content. This study addressed the combined or individual soil application of dolomite and compost to remediate a soil contaminated with mining waste to evaluate synergistic effects on pH buffering, metal availability, organic complexation, phytotoxicity reduction, and microbial activation. An experimental design was carried out with nine combinations of compost and dolomite doses. Compost increased soil organic matter by 1 and 3 %, and dolomite increased soil pH from 2.6 to 4.5 and 6.5. An incubation test was performed for 69 days and microbial activity was monitored. Physicochemical and microbiological parameters were measured, and Allium cepa tests were conducted. Greater microbial biomass (194.2 ± 31.6 mg C/kg) and CO₂ release (176.8 ± 5.6 mg CO₂-C) were observed in remediated soils with high dolomite and low compost doses (p < 0.05). Soils with high dolomite dose were associated with a decrease in electrical conductivity (11.18-1.43 mS/cm), redox potential (415-240 mV) and toxicity (RGIC_0.8: 0.12 to >100), but an increase in Pb, Cu and Zn immobilization, pH (2.91-7.18) and carbonates (11.41-40.95 %). Therefore, dolomite application generated a dose-dependent improvement in physicochemical and biological conditions and significantly decreased the cytotoxicity and genotoxicity. The combined use of high dolomite and low compost doses (23.63 g dolomite and 4.05 g compost/100 g soil) represents an upper-bound remediation scenario and provides a reference framework for amendment-driven processes in extremely contaminated soils, warranting further validation in small-scale trials before field application.