Groundwater is a vital natural resource that has been extensively used but, unfortunately, polluted by human activities, posing a potential threat to human health. Groundwater in the Yinchuan Region is contaminated with NO, which is harmful to the local population. This study utilized the eXtreme Gradient Boosting (XGBoost) model with the SHapley Additive exPlanations (SHAP) method to identify the key factors influencing groundwater nitrate pollution in the Yinchuan Region. The SHAP feature dependence plots revealed the intricate relationship between NO levels and TDS, Mn, TFe, and pH in complex groundwater systems. The results indicate that the high levels of groundwater NO are primarily caused by the combined effect of irrigation water from the Yellow River, shallow groundwater depth, unfavorable drainage, water recharge, overuse of fertilizers, and geological factors such as weathering nitrogen-bearing rocks. Hydrochemical parameters such as Mn, Fe, and pH create a strong reducing groundwater environment, resulting in lower NO concentrations in this region. Well depth and soil organic carbon at a depth of 80-100 cm have a negative impact on NO concentrations; conversely, sand in soil depths 0-20 cm and 100-150 cm and climatic factors such as precipitation have a weak but positive effect on the level of NO in groundwater in the region. The recommendation is to quickly and extensively implement a farming water-conservancy transformation project, reducing water-intensive crops, promoting groundwater use for irrigation in areas where soil salinization is a concern are proposed. This research could provide local agencies with a scientific foundation for sustainable management of farming and groundwater in the Yinchuan Region, ultimately benefiting the entire Yinchuan Plain.

In the homologous series of polybrominated diphenyl ethers (PBDEs), the debromination of low-brominated diphenyl ethers with higher toxicity remains a challenge. Nano zero-valent iron (nZVI) has been extensively studied for the debromination of PBDEs, but its inherent direct electron transfer mechanism is less efficient for low-brominated diphenyl ethers, and there are issues with high preparation costs. In this work, we synthesize Ni-doped oxalated submicron ZVI (Fe/Ni) using a low-cost ball-milling method. Fe/Ni exhibits a debromination rate constant of 0.48 day for 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) in tetrahydrofuran (THF)/water. The debromination rate of Fe/Ni for BDE-47 in water is even faster (0.98 day), with the yield of the complete debromination product, diphenyl ether, reaching 76.71%. In real groundwater, Fe/Ni also shows high reactivity toward BDE-47, with a rate constant of 0.33 day. Kinetic experiments, quenching experiments, and degradation pathway indicate that the attack of atomic hydrogen on C-Br bonds is the primary degradation mechanism. Electrochemical analysis further show that Ni sites could cleave hydrogen into absorbed atomic hydrogen (H*) and adsorbed atomic hydrogen (H*), with H* playing the main role. These findings contribute valuable insights into advancing the large-scale application of ZVI and offer promising strategies for thorough remediation of PBDEs pollution.

The leaves of trees and shrubs can capture atmospheric pollutants such as polycyclic aromatic hydrocarbons (PAHs), and the capacity of uptake depends on the leaf traits. Although numerous studies have measured PAH concentrations in leaves of woody plants and the variability in leaf traits, few have investigated the relationship between these factors. We conducted a literature review to summarize the available information on this topic and found that five types of leaf traits have been studied, with those associated with leaf morphology and gas exchange being the most common. However, the results of the studies are often contradictory. To address these discrepancies, we conducted a meta-analysis to examine how PAH uptake by woody species is affected by leaf ecological traits associated with morphology (leaf area, specific leaf area [SLA], leaf thickness and leaf width/length ratio [W/L]) and with gas exchange (stomatal conductance, leaf carbon isotopic signature [δC] and stomatal density). The meta-analysis included studies involving at least two different species with comparable PAH concentrations. Many of the studies did not examine the relationship between ecological traits and PAH concentration, and those that did often involve different traits. We therefore used the TRY Plant Trait Database data as the standard source of trait data. Relationships were analyzed by determining differences regarding PAHs and traits and calculating Spearman correlations and their significance. The leaf morphology traits were more closely correlated with PAH concentrations than the gas exchange traits. Thus, morphological traits such as SLA and leaf area can be considered significant predictors of PAH uptake, especially for particulate-associated PAHs. Gas exchange traits showed less consistent correlations, indicating the complexity of factors influencing PAH uptake in leaves. This study highlights the importance of considering multiple leaf traits in order to better understand and predict PAH uptake in woody plants.

Obtaining the high-resolution distribution characteristics of urban air pollutants is crucial for effective pollution control and public health. In order to fulfill it, mobile monitoring offers a novel and practical approach compared to traditional fixed monitoring methods. However, the sparsity of mobile monitoring data still makes it a challenge to recover the high-resolution pollutant concentration across an entire area. To tackle the sparsity issue and fulfill a prediction of the spatiotemporal distribution of PM, a high-resolution urban PM prediction method was proposed based on mobile monitoring data in this study. This method enables prediction with a spatial resolution of 500m × 500m and a temporal resolution of 1 hour. First, a Light Gradient Boosting Machine (LightGBM) was trained using mobile monitoring of PM concentration and exogenous features to obtain complete spatiotemporal PM concentration. Second, a model consisting of Convolutional Neural Network and Transformer (CNN-Transformer) with a customised loss function was established to predict high-resolution PM concentration based on complete spatiotemporal data. The method was validated using real-world data collected from Cangzhou, China. The numerical results from cross-validation showed an R of 0.925 for imputation and 0.887 for prediction, demonstrating this method is suitable for high-resolution spatiotemporal prediction of PM concentration based on mobile monitoring data.

The emission factors and characteristics of pollutants from river vessels are critical for understanding the environmental impact of ship emissions, particularly in inland waterways. However, research gaps remain regarding emissions of volatile organic compounds (VOCs) and intermediate-volatility organic compounds (IVOCs) from river vessels. In this study, we collected and analyzed organic vapor emissions, including non-methane hydrocarbon (NMHCs), oxygenated volatile organic compounds (OVOCs) and IVOCs, from three river vessels under different operating conditions. The results show that the average emission factors of NMHCs, and IVOCs from river vessels are significantly higher than those from ocean-going vessels. Inland waterways' proximity to residential areas increases the risk of pollutant transport to urban environments, heightening the importance of managing river vessel emissions. Notably, older auxiliary engines displayed higher organic vapor emissions compared to main engines, underscoring the need for better control measures for aging engines. By analyzing the emission characteristics of organic vapors from river vessels, it was found that, unlike other pollution sources where C12 n-alkanes are the major contributors of IVOCs, the contributions of C12-C15 n-alkanes in river vessel exhaust are similar, with C14 n-alkane having the highest contribution. OVOCs constituted more than 50% to ozone formation potentials of organic vapors, while IVOCs were responsible for over 90% of the secondary organic aerosol (SOA) formation. Given these findings, targeted efforts to reduce OVOCs and IVOCs emissions from river vessels should prioritized to mitigate their environmental impact.

Microplastics (MPs) have emerged as hazardous substances, eliciting widespread concern regarding their potential toxicity. Although our previous research has indicated that polystyrene MPs (PS-MPs) might cause male reproductive toxicity in mammals, their precise effects on sperm motility parameters and acrosomal development remain uncertain. Herein, the effects on sperm motility of PS-MPs at varied particle sizes (0.5 μm, 4 μm and 10 μm) and the underlying mechanisms were examined. The results revealed that PS-MPs caused a decrease in sperm motility, accompanied by abnormalities in the structure and function of the sperm acrosome. Meanwhile, PS-MPs triggered the elevation of intracellular reactive oxygen species levels and the abnormal expression of antioxidant enzymes (γH2AX, GPX4, Peroxiredoxin 5 and SDHB), indicating disruption of the sperm antioxidant system. Furthermore, we observed aberrant expression of key factors involved in mitochondrial fission/fusion (Drp1, Fis1, Mfn1, Mfn2) and biogenesis (Tfam, Nrf1, Pgc1α), potentially resulting in disrupted mitochondrial dynamics and biogenesis in mice testis and Sertoli cells exposed to PS-MPs. Additionally, PS-MPs induced mitochondrial dysfunction by regulating the Sirt1-Pgc1α signaling pathway. Our data provided novel insights into potential mechanisms underlying the spermatogenesis disorders triggered by PS-MPs.

An in-depth investigation of the maximum environmental load is crucial for soil security and pollution prevention. This research focused on soil environmental carrying capacity (SECC) for different risk receptors in a Chinese industrial city. By determining risk threshold for various land use types, we integrated mass balance and iterative models to capture dynamic net input fluxes with spatial heterogeneity. This enabled quantitative characterization of Benzo(a)pyrene (BaP) SECC through top-down and bottom-up approaches (corresponding to duration (D) and rate of regional emission, respectively). The thresholds were in the order of agricultural land < residential land < forest < industrial land < park. The top-down analysis showed D increased ∼1.5x with a 5% input flux decline until 2031. The bottom-up analysis suggested industrial emissions decreased by approximately 10% as the pollution control period was extended from 20 to 50 years. Both methods showed that at maximum background values (C), D was ∼4x and the industrial emission rate was ∼10% higher than at minimum C. SECC values near industrial areas significantly decreased, even reaching negative values, signifying complete carrying capacity loss. This study provided an approach to the dynamics of SECC under diverse scenarios, aiding informed decision-making for sustainable land management.

Perfluorooctanesulfonate (PFOS), a persistent organic pollutant, poses significant ecological risks. This study investigates the effects of PFOS on rhizosphere microbial communities of two wetland plants, Lythrum salicaria (LS) and Phragmites communis (PC). We conducted microcosm experiments to analyze the physiological status of soil microbes under varying PFOS concentrations and examined the role of root exudates in modulating PFOS mobility. Flow cytometry and soil respiration measurements revealed that PFOS exposure increased microbial mortality, with differential impacts observed between LS and PC rhizospheres. LS root exudates intensified microbial stress, whereas PC exudates mitigated PFOS toxicity. Thin-layer chromatography indicated that LS exudates decreased PFOS mobility, leading to higher local concentrations and increased microbial toxicity, while PC exudates enhanced PFOS mobility, reducing its local impact. Fourier-transform infrared spectroscopy and excitation-emission matrix fluorescence spectroscopy of root exudates identified compositional shifts under PFOS stress, highlighting distinct defense strategies in LS and PC. These findings underscore the importance of plant-microbe interactions and root exudate composition in determining microbial resilience to PFOS contamination.

Contaminants are transported into estuaries during rainfall events, impacting the physiology of harvested species, and thereby threatening fisheries sustainability. Decapod crustaceans are among the most economically important groups harvested from estuaries, but are at high risk of contaminant exposure. We conducted a systematic review and meta-analysis evaluating the physiological responses of harvested estuarine decapods to contaminants and flooding. A total of 138 research articles were identified, with global research effort corresponding to the geographic distribution of crustacean harvesting. From these studies, 305 acute toxicity values for metals and pesticide chemical classes were extracted and 341 sublethal effect sizes (log-response ratios; LnRRs) calculated using 91 physiological measures across seven response categories. At sublethal environmentally relevant concentrations, exposure to various metals, pesticide chemical classes and polycyclic aromatic hydrocarbons consistently elicited negative effects on decapod physiology (LnRR range: -0.67 to -0.07). Key physiological processes impacted by contaminant exposure included nutritional condition, osmoregulation, oxidative stress defences, acetylcholinesterase activity, metabolism and growth (LnRR range: -0.73 to -0.1), with a general trend for greater effects later in ontogeny. With new agricultural and industrial chemicals continually being marketed, our meta-analysis highlights the need for regulatory testing on harvested species prior to registration for use in catchment areas. Under future climatic variability, harvested estuarine decapods may be increasingly exposed to contaminants, with implications for fisheries and global food security.

Carbonaceous aerosols primarily comprise organic carbon (OC) and black carbon (BC). Thermal-optical analysis (TOA) is the most commonly used method for separating carbonaceous aerosols into OC and EC (BC is referred to as elemental carbon EC, in this method). Advances in hardware design and algorithms have expanded the capabilities of TOA beyond just distinguishing OC and EC. However, a comprehensive understanding of the enhanced functionality of TOA is still lacking. This study provides the first comprehensive review of the TOA technique, highlighting expanded capabilities to measure brown carbon (BrC), mass-absorption efficiency, absorption enhancement, source contributions, and refined OC/EC split points. This review discusses the principles, advantages, and limitations of these advancements. Furthermore, the TOA system anticipates further advancements through integration with other instruments, establishing correlations between EC values obtained from different TOA instruments/protocols, correlating between BrC measurements from TOA and non-TOA methods, and developing an algorithm to quantify BrC from progressive absorption Ångström exponent (AAE) values. This review enhances the understanding of the TOA system and its implication for air quality and atmospheric radiation research.

Daily dietary intake inevitably exposes individuals to various natural toxins, which may pose potential health threats. Focusing only on specific toxins could underestimate dietary risks. Therefore, we have developed a suspect and nontarget method based on ultrahigh-performance liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS) to screen both known and unknown natural toxins in various foodstuffs. An in-house database containing 2952 natural toxins including fungal toxins, phytotoxins, animal toxins and cyanotoxins was established, facilitating suspect screening. Predicted retention time and mass spectrometry data were employed to enhance the confidence levels. Subsequently, Nontarget screening method was conducted based on molecular network analysis, annotating the edges and nodes through modified types and fragmentation characteristics. Finally, we analyzed 102 foodstuff samples and identified a total of 90 natural toxins, including mycotoxins and phytotoxins, with 65 identified by suspect screening and 25 by nontarget screening. Based on measured concentrations, the daily per capita dietary intake of total natural toxins was estimated, it was below risk doses for natural toxins with available reference values. Overall, this work established a novel method for the comprehensive identification of natural toxins in foodstuffs and emphasized the importance of dietary risk assessment for natural toxins.

Accurate predictions of atmospheric particulate matter can be applied in providing services for air pollution prevention and control. However, the forecasting accuracy of traditional air quality models is limited owing to model uncertainties. In this study, we developed a deep learning model, named multiscale depth-separable UNet (MDS-UNet), to improve PM and PM concentration forecasts from WRF_Chem over China. Results showed that MDS-UNet was able to capture the complex nonlinear errors between model predictions and observations, which was helpful in correcting the biases and spatiotemporal distribution patterns of PM and PM concentrations predicted by WRF_Chem. MDS-UNet made a better performance in the improvement of both PM and PM prediction accuracy than UNet and CNN during the 0-24 forecasts. Using MDS-UNet, the reductions in the root-mean-square error (RMSE) of the regionally averaged PM and PM concentration forecasts were 35.08% and 17.74%, respectively. During the 0-24-h forecast period, MDS-UNet performed well in terms of PM and PM over six key urban agglomerations in China. Taking a pollution process as a case study, results demonstrated that, compared with WRF_Chem, MDS-UNet was able to make the best improvement in YRD, the Sichuan Basin, and central China, with reductions in the RMSE of the PM forecasts of 55.22%, 55.53%, and 52.17%, respectively; and for PM forecasts these reductions were 44.90%, 40.97%, and 46.79%, respectively. Through this analysis, it was apparent that MDS-UNet demonstrated a better effect in terms of improving both PM and PM predictions in these key urban agglomerations during an important pollution process.

To address plastic pollution in agricultural soils due to polyethylene plastic film mulch used, biodegradable film is being studied as a promising alternative material for sustainable agriculture. However, the impact of biodegradable and polyethylene microplastics on soil carbon remains unclear. The field experiment was conducted with Poly (butyleneadipate-co-terephthalate) debris (PBAT-D, 0.5-2 cm), low-density polyethylene debris (LDPE-D, 0.5-2 cm) and microplastic (LDPE-Mi, 500-1000 μm) contaminated soil (0% (control), 0.05%, 0.1%, 0.2%, 0.5%, 1% and 2% w:w) planted with soybean, to explore potential impacts on soil respiration (Rs), soil organic carbon (SOC) and carbon fractions (microbial biomass carbon (MBC), dissolved organic carbon (DOC), easily oxidizable carbon (EOC), particulate organic carbon (POC), mineral-associated organic carbon (MAOC)), and C-enzymes (β-glucosidase, β-xylosidase, cellobiohydrolase). Results showed that PBAT-D, LDPE-D and LDPE-Mi significantly inhibited Rs compared with the control during the flowering and harvesting stages (p<0.05). SOC significantly increased in the PBAT-D treatments at both stages, and in the LDPE-Mi treatments at the harvesting stage, but decreased in the LDPE-D treatments at the flowering stage. In the PBAT-D treatments, POC increased but DOC and MAOC decreased at both stages. In the LDPE-D treatments, MBC, DOC and EOC significantly decreased but POC increased at both stages. In the LDPE-Mi treatments, MBC and DOC significantly decreased at the harvesting stage, while EOC and MAOC decreased but POC increased at the flowering stage. For C-enzymes, no significant inhibition was observed at the flowering stage, but they were significantly inhibited in all treatments at the harvesting stage. It is concluded that PBAT-D facilitates soil carbon sequestration, which may potentially alter the soil carbon pool and carbon emissions. The key significance of this study is to explore the overall effects of different forms of plastic pollution on soil carbon dynamics, and to inform future efforts to control plastic pollution in farmlands.

Understanding variations in total mercury (T-Hg) levels in fish is crucial for protecting aquatic biota and human health. This article evaluates the influence of environmental factors (temperature, pH) and biological variables (feeding habits, trophic level, total length, total weight), on T-Hg concentrations in fish from the Atrato River basin, Colombia. Utilizing a robust secondary data set of 842 fish samples from 16 species collected in 2019, we conducted a comprehensive analysis of these influences. We examined differences in T-Hg accumulation rates by habitat type (pelagic, benthopelagic and demersal) and probabilistically classified species based on their feeding habits and trophic levels. Our analysis identified a hierarchy of variables influencing T-Hg levels: feeding habits > total length > estimated total weight > trophic level > water temperature > pH, with temperature being the only predictor exerting a negative influence. Together, these variables accounted for over 60% of the variability in T-Hg accumulation in fish muscle tissue. Furthermore, fish in the Atrato River exhibited differential T-Hg based on habitat type, grouping into three distinct subpopulations stratified by feeding habits and trophic levels. These findings suggest that observed T-Hg accumulation patterns are driven by the functional ecology of the organisms, phenological characteristics, metabolism, contamination patterns, biogeography, land use, and the spatial and chemical configuration of the environmental matrices of the basin. Our results emphasize the importance of understand how biological and environmental factors influence T-Hg concentrations in fish, as these factors vary across aquatic systems. This knowledge is crucial for developing effective biodiversity management strategies. While we used a machine learning approach to identify key predictors of T-Hg accumulation, we also caution against potential biases in modeling T-Hg concentrations for aquatic biota management.

Aquatic environments serve as ideal reservoirs for antibiotic-resistant bacteria and resistance genes. However, the presence of polymyxin-resistant Yersinia enterocolitica, the pathogen responsible for human yersiniosis, in aquatic environments remains poorly understood. Herein, we isolated polymyxin-resistant Y. enterocolitica strains from natural water for the first time. In addition to intrinsic resistance to ampicillin and cefazolin, the strains demonstrated high resistance to polymyxin B and polymyxin E. All isolates were capable of biofilm production and exerted high virulent effects in Galleria mellonella, with 90% mortality occurring within 48 h post-infection. Furthermore, whole genome sequencing identified 26 antibiotic resistance genes, including polymyxin resistance determinants (arnA and PmrF), beta-lactam resistance determinants (vatF and blaA), and 60 virulence genes such as yaxA and yaxB in Y. enterocolitica isolates. Notably, phylogenetic analysis revealed that Y. enterocolitica involved multilocus sequence types ST937 and ST631, which were clustered with strains isolated from a human in the United States or swine in China. The close relatedness to clinical isolates suggests that polymyxin-resistant Y. enterocolitica may pose considerable health risk to humans. Our findings provide evidence of the presence of polymyxin-resistant Y. enterocolitica in aquatic environments and raise concerns about health risks due to their potential high virulence.

A major alternative to bisphenol A (BPA), fluorene-9-bisphenol (BHPF) has been shown to cause multiorgan toxicity. However, its reproductive toxicity and the underlying biological mechanism remain largely unknown. Recently, changes in the gut microbiota and metablome caused by environmental contaminant exposure and their potential impact on male reproductive health have been of great concern. Therefore, we aimed to elucidate the underlying mechanism of BHPF-related fertility impairment by integrating metabolome and microbiome analysis. In the present study, we showed that BHPF exposure caused testicular dysfunction with impaired spermatogenesis and disrupted steroid hormone synthesis. Mechanistically, altered gut microbiota and metabolites were revealed by 16S rDNA sequencing and untargeted metabolomics analysis. Subsequent multi-omics combination analysis revealed a strong correlation between altered microbiota and lipid metabolites. We also found a strong relationship between lipid metabolites and sperm parameters such as sperm concentration, sperm motility, etc. Most importantly, these findings provide new insights into the mechanistic scenario underlying BHPF-induced fertility toxicity, that disrupted lipid metabolism caused by gut microbiota dysbiosis may be a reason for reproductive impairment caused by BHPF exposure.

The increase in wildfires and bushfires due to climate change means that more people, including pregnant women and their fetuses will be exposed to landscape fire smoke. Although there is evidence to suggest that pregnancy landscape fire exposure is associated with lower birth weight, preterm birth and pregnancy loss, there is a lack of information on many other perinatal outcomes, as well as information on subsequent respiratory outcomes in children. Furthermore, due to the generally short term (hours/ days) and intermittent nature of landscape fire smoke exposure, the knowledge to date has largely relied on natural experiments and ecological studies which can be subject to misclassification of exposure and a lack of precision. On the other hand, general urban outdoor air pollution exposure during pregnancy and subsequent perinatal and respiratory effects has been well studied. In particular, as air exposure modelling has improved so have the adaptations of methods to analyze the effects of air pollution exposure during pregnancy enabling critical windows of exposure to be identified. In this narrative review we summarize the current state of knowledge about the perinatal and respiratory effects of pregnancy landscape fire and particulate matter <2.5μm in diameter (PM) air pollution exposure, including a comment on analysis methods to date, and an assessment of how methodologies used in general air pollution research in relation to pregnancy exposure can be further harnessed for landscape fire smoke exposure pregnancy research.

Breast cancer (BC) is the most common malignancy in women and the leading cause of cancer death. Microplastics (MPs) are plastic fragments with a diameter of less than 5 mm, easily ingested by organisms. Although MPs have been reported to enter the human body through diet, surgery, etc., whether MPs accumulate in BC and their effects have been largely unknown. Our study revealed a significant accumulation of MPs in BC patient samples. MPs pull-down experiments and mass spectrometry (MS) studies showed that MPs bound to annexin A2 (ANXA2) and were endocytosed into cells. This process resulted in mitochondrial damage and subsequent induction of mitophagy. Furthermore, after binding to ANXA2, MPs regulated mitophagy by inhibiting IL-17 exocytosis. These findings revealed the mechanism of toxic effects of MPs in patients with BC, clarified the molecular mechanism of ANXA2-IL-17 signaling pathway causing mitochondrial damage by MPs, and suggested the potential toxic effects and toxicological mechanisms of MPs.

Mineral exploitation is one of the human activities that seriously affect freshwater ecosystems. It is of great significance to study the impact of mining on the α and β diversity of macroinvertebrates. This study reveals the response of taxonomic and functional α and β diversity of macroinvertebrates to mining activities in the Luanchuan molybdenum mining area. A total of 40 sets of macroinvertebrates, sediment and water samples in the Taowan North River (TR), Yu River (UR) and Hongluo River (HR) in the molybdenum mining area were collected. The results show that: 1) the mining activities led to obvious differences in the environmental factors of the three rivers. The heavy metals in the sediments and water bodies of TR and UR showed different degrees of exceedance, while there was no exceedance of heavy metals in HR; 2) The taxonomic and functional α diversity was much lower in the TR and the UR than in the HR. The concentrations of heavy metals in sediments and water bodies were significantly negatively correlated with the taxonomic and functional α diversity; 3) Mineral extraction resulted in significant differences in macroinvertebrate β diversity among the three rivers. The taxonomic and functional β diversity of the macroinvertebrate communities in TR and UR was much higher than that in HR. The turnover and nestedness of functional β diversity showed significant differences. Functional β diversity was more obviously affected by heavy metal exceedance than taxonomic β diversity. Nestedness were more sensitive to exceedance of heavy metals than turnover. The results of this study can provide a theoretical basis for ecological restoration and protection of rivers in mining areas.

Environmental safety has become a major concern in recent years due to the global increase in microplastic pollution. These ubiquitous, tiny, and potentially toxic plastic particles enter aquatic environments through weathering of larger plastics and the release of microbeads. Although numerous studies have focused on microplastic pollution in developed regions, information from developing countries remains limited. This study assessed the presence of MPs and associated oxidative stress responses in two commercial fish species, Clarias gariepinus (Catfish) and Oreochromis niloticus (Nile Tilapia), from Kubanni reservoir, Zaria, Nigeria, over six months spanning both the dry and rainy seasons. Fibers were identified as the most abundant MP particles, followed by fragments, films, and beads, in the order of fibers > fragments > films > beads. The highest fiber concentrations were recorded in the gills, with Clarias garipinus showing 11.5 MP items/individual and Oreochromis niloticus showing 22.5 MP items/individual. Black microplastics were predominant, and the most common ingested MP ranged from 1.0 to 2.0 mm. The primary polymers identified were polypropylene and polyethylene terephthalate. Evidence of oxidative stress and cellular damage was observed in the gills, liver, and dorsal muscles of both fish species, which correlated with MPs ingestion. According to recommendations from the European Food Safety Authority regarding fish consumption by children and adults, individuals consuming Clarias gariepinus and Oreochromis niloticus from the Kubanni reservoir may be exposed to between 70 and 700 MP items/organ. The risk associated with consuming MPs found in fish gills and guts was notably higher, posing significant concerns for human health. This study provides insights into microplastic contamination in commercially important fish from the Kubanni Reservoir and highlights the environmental and public health risks associated with consuming contaminated fish from this ecosystem.

Elucidating the chemical composition, sources, and health risks of fine particulate matter (PM) is crucial for effectively preventing and controlling air pollution. This study collected PM samples in Linyi from November 10, 2021, to October 15, 2022, spanning the period of the 2022 Winter Olympics and Paralympics. The analysis focused on seasonal variations in the chemical composition of PM, including water-soluble ions, inorganic elements, and carbonaceous aerosols. Results from the random forest model indicated that control measures during the Olympics and Paralympics reduced PM concentrations by 21.5% in Linyi. Organic matter was the dominant component of PM, followed by NO, SO, and NH. Among secondary inorganic ions, SO exhibited the highest concentration in summer, while NO and NH showed the lowest concentrations. The inorganic elements S, K, Fe, and Si had high mean annual concentrations, underscoring the need for targeted control measures for plate production, bulk coal burning, and biomass combustion in Linyi. The organic carbon (OC) to elemental carbon ratio (17.7-20.5) in Linyi was high, highlighting the importance of addressing secondary OC pollution. According to the positive matrix factorization model, coal burning, and the secondary formation processes of sulfate and nitrate were the dominant sources of PM. Backward air mass trajectories revealed substantial contributions from the southeastern, local, and southwestern regions of Linyi. This suggests the need for enhanced regional joint prevention and control efforts between Linyi and neighboring cities, such as Rizhao and Jining in Shandong Province, as well as northern cities in Jiangsu Province. The highest non-carcinogenic and carcinogenic risks (CRs) were associated with As. coal burning posed significant noncarcinogenic risks and a moderate CR, contributing 41.7% and 44.0% of the total health risk, respectively. These findings are crucial for developing effective air pollution prevention and control strategies.