High Pollutant Concentrations Research Articles

Validation of a computational model for atmospheric pollution emanating from an industrial chimney using a solar based instrumentation system

This study examines the atmospheric dispersion of pollutants from industrial chimneys, highlighting the importance of assessments both before and after installation to safeguard public health and the environment. A Vantage Pro2 Plus weather station, powered by a solar panel, was used to continuously collect accurate meteorological data, which informed a Gaussian model for pollutant dispersion. The results revealed that the predominant wind direction is towards the east, with pollution mainly affecting areas between the southeast and northeast. Seasonal variations showed broader dispersion during winter that exceeds 4500 meters of large at a distance of 10 kilometers from the source during the day and higher pollutant concentrations at night that can reach 5.10-6 g/s, compared to a maximum of 10-6 g/s during other times. The study demonstrates that lower temperatures result in higher concentrations over smaller areas, whereas higher temperatures cause wider dispersion with lower concentrations. These findings support decision-making for optimal chimney placement, ongoing monitoring, and emergency planning. The integration of solar-powered weather stations and real-time data visualization significantly improves the efficiency of environmental monitoring and management.

Utilizing Electrooxidation for Textile Effluent Wastewater Treatment and Simultaneous Electrocatalytic Hydrogen Production: Transforming Waste into Energy and Promoting Water Reuse in a Circular Economy Context

Textile effluent wastewater poses a serious environmental risk because of its high concentration of pollutants, which include organic compounds, heavy metals, and dyes. The present study investigates the technical and economic feasibility of hybrid water electrolysis performances. Specifically, real textile effluent wastewater was utilised to examine simultaneous abatement and electrochemical hydrogen production. The treated water can be recycled in the textile mill, offering the benefits of trash-to-treasure and cost savings through the circular economy. In addition to reducing the environmental impact of textile wastewater, the synergistic approach seeks to maximise its potential for producing hydrogen as clean energy. Here, the commercially available stainless sheet was used as the anode in the electrochemical setup system and the two-dimensional Ti3C2TX MXene was used as the catalyst embedded cathode. The optimal electrode-electrolyte parameter settings resulted in an 83% decrease in COD level and a degradation efficiency of about 88%. The potential for widespread adoption in the textile industry is highlighted by the discussion of the economic viability and environmental advantages of using wastewater from textile effluents for pollutant degradation and hydrogen production. Hence, the energy estimation was looked at and estimated in order to evaluate the process viability. For instance, the hybrid electrolysis process uses a very small amount of electricity (0.825 kWh m-3 order-1) and has an apparent operating current (30 mA/cm2). This work could serve as a guide for the methodical assessment and choice of hybrid water electrolysis using actual wastewater. The electrode's recyclability and reuse were proven for possible commercial applications. The stability of the Ti3C2TX electrode over a wide pH range was investigated in order to produce hydrogen on a big scale at a reasonable cost.

Hierarchically-porous resin for the adsorption of organic matter in raffinate produced by solvent extraction from the vanadium industry

Solvent extraction wastewater contains high concentrations of organic pollutants and metal ions, making it difficult to treat. This paper presents a method of using hierarchically-porous adsorption resin to recover organics from raffinate and regenerate the resin, addressing secondary pollution in extraction processes. The chosen resin, WS6108, removes over 95 % of organics from raffinate, with high metal ion concentrations enhancing its adsorption efficiency. The article conducted an optimization experiment and mechanism study on WS6108 resin for adsorbing organic matter in vanadium raffinate (OIVR), followed by desorption and recycling tests. Results showed WS6108 resin achieved a 96.7 % adsorption efficiency at a solid–liquid ratio of 24 g/L after optimization. The chosen methanol desorbent achieves over 99 % desorption efficiency for the WS6108 cycle under specific conditions. The resin’s performance remains stable for up to 45 cycles. Adsorption isotherms and kinetic experiments indicate that OIVR adsorption by WS6108 resin is endothermic, non-spontaneous and entropy increasing. Moreover, the adsorption kinetics of OIVR by WS6108 resin followed a pseudo-second-order model, based on the activation energy, liquid film diffusion was considered the main rate-controlling step. A column experiment was conducted to verify that WS6108 resin can be used in real vanadium raffinate to remove organics. Density functional theory (DFT) revealed that strong hydrogen bonding, π-π stacking and excellent adsorption diffusion behavior drive OIVR adsorption. This study aims to increase the use of adsorption to treat oily wastewater generated by solvent extraction.

Variations in air pollution before, during and after the COVID-19 lockdown in Peruvian cities.

The high concentrations of air pollutants in Peru remain a persistent problem, significantly impacting public health. Understanding the extent to which the COVID-19 lockdown affected these contaminants is crucial. To determine variations in NO2, O3, CO, and SO2 concentrations in 10 Peruvian cities before, during, and after lockdown. A comparative ecological study was conducted in urban areas of 10 major Peruvian cities using the Google Earth Engine (GEE) platform. Data on atmospheric pollutant concentrations were extracted from the Sentinel-5P/TROPOMI satellite images for the period between March 16 and June 30, across the years 2019, 2020, 2021, and 2022, for comparative analysis. The Wilcoxon test was used to evaluate changes between the study periods. We included 10 urban cities located across three geographic regions of Peru. Most urban cities experienced a decrease in NO2 concentrations and an increase in O3 and CO levels during the lockdown, while SO2 concentrations remained relatively constant. The lockdown has caused variations in NO2, O3 and CO concentrations. Future studies with accurate data on air pollutant concentrations are needed to ensure targeted and effective interventions.

Study on the degradation performance of coking wastewater using an in-situ enhanced Fe2+/Fe3+ cycle dual-cathode Electro-Fenton system

Coking wastewater, characterized by its complex composition, high pollutant concentration, and poor biodegradability, poses a significant challenge for wastewater treatment. In this study, a chitosan-based mesoporous carbon (CPC) and microporous carbon (ZPC) dual-cathode Electro-Fenton system was developed to enhance the in-situ Fe2+/Fe3+ cycle efficiency for the degradation of coking wastewater. The optimal preparation conditions for both electrodes were investigated, as well as the primary factors affecting the degradation performance of the dual-cathode Electro-Fenton system. When the functional carbon loading was 17.5 mg/cm2 and a current of 600 mA was applied, the CPC electrode produced 842 mg/L of H2O2 within 30 min, and the Fe2+/Fe3+ cycle efficiency of the ZPC electrode reached 85.23 %. The initial pH and current intensity had the most significant impact on the degradation efficiency of coking wastewater, achieving a COD degradation rate of 78 % at an initial pH of 3.5 and a current intensity of 600 mA. GC-MS analysis indicated that under 600 mA, nitrogen-containing organics, ethers, and alcohols in the coking wastewater were completely removed. The degradation of simulated wastewater showed that the presence of oxygen-containing compounds inhibited the degradation of nitrogen-containing organics. However, the dual-cathode system experienced significant electrode wear, with reduced hydrophobicity and agglomeration of Fe3+ on the electrode surface impacting its cyclic stability.

Direct current cardioversion and the impact of short-term exposure to air pollution: a report from the nationwide EP-PARTICLES study

Abstract Background Air pollution and atrial fibrillation (AF) represent significant public health challenges, impacting global health considerably. Numerous studies have focused on areas with high or very high air pollution concentrations, our study examines a unique area in Poland characterized by low to moderate air pollution levels. Our research also addresses a commonly overlooked in research type of pollution - Polish smog. Due to its composition rich in particulate matter and the conditions in which it is formed - is characterized by extremely adverse health effects. Aim To explore the correlation between short-term air pollution exposure and the incidence of acute direct current cardioversion (DCC) for AF treatment. Methods The study area encompassed three voivodeships from Eastern Poland at the NUTS-2 level, with a population of 5,429,378 individuals. Data on hospitalizations from 2011 to 2020 were obtained from the National Health Fund. We combined air pollution and weather condition data from both ground monitoring stations and satellite observations. Emergency visits for AF and DCC were identified using ICD-9 and ICD-10 codes. For a national perspective, we applied meta-analytical strategies to the municipality-specific outcomes. The results are presented as percentage increases in admissions (% IR) with 95% confidence intervals (95%CI). Results Over the decade, 190,454 hospitalizations for AF were reported with a standardized hospitalization rate (SHR) of 358 per 100,000/year (SD=113) and 30,291 DCC admissions (SHR=56.9 [SD]=26). The mean age for AF vs. DCC cohort was 69.6 (SD=11.2) vs. 68.7 (SD=10.4) years, with females representing 56.1% (N=106,822) of AF cases vs. 46.1% (N=13,953) of DCC admissions (P<0.001). Each 10 µg/m3 increase in PM2.5, PM10, and NO2 concentration on the exposure day led to 1.6% (1.1%–2.1%), 1% (0.8%–1.6%), and 1.8% (1.1%–2.6%) increases in acute AF admissions, respectively, with effects lasting up to 6 days. Women and older individuals were more vulnerable to AF episodes induced by air pollution (P<0.001). A 10 µg/m3 increase in PM2.5 on the day of admission increased DCC admissions by 1.5% (0.1%–2.9%, P=0.04), with effects persisting for up to 3 days. The impact of PM10 was time-delayed: 1.3% (0.2%–2.4%, P=0.02) for LAG1 (i.e. one day after exposure), and 1.1% (0.1%–2.2%, P=0.4) for LAG2. No significant effects of gaseous pollutants on DCC (SO2, NO2, and BaP) were observed, nor any differences in the effects by age or sex. Exposure-response functions show steeper slopes of the PM2.5 associations in the lower ranges of exposures, far below air quality norms set by the World Health Organization. Conclusions Air pollution acts as a triggering factor for acute AF hospitalizations and DCC. The differential impact of air pollution on AF events between groups highlights that women and older individuals are particularly vulnerable. Air pollution exposure should be considered into AF management and prevention strategies.Pooled exposure–response function: % inc

Comparison of different geometry trees in fire simulation

AbstractWildfire simulations can help to better understand the dynamics and effects of forest fires. The basis of wildfire simulation is the tree-burning simulation. In this paper, the fire simulation of 7 different geometry Hungarian trees in the case of arson is presented. It was observed that the trees were burned down fast. The maximum mass loss rate and maximum heat release rate were larger as the tree was larger. The largest intensity fire could be observed in the case of the smallest tree. The maximum temperature was higher in the case of a large crown diameter. The maximum aerosol reached high pollutant concentrations. In the case of large crown height, the maximum CO2 concentration was higher. The results presented in this paper can be the basis of the following forest fire simulations.

Sustainable approach for landfill leachate treatment through dielectric barrier discharge/ferrate (DBD/Fe(VI)) enhanced nanofiltration

Landfill leachate, with its high concentrations of persistent organic pollutants, salts, heavy metals, and emerging contaminants, presents significant environmental challenges. This study investigated the combination of dielectric barrier discharge (DBD) and ferrate (Fe(VI)) pretreatment technology in landfill leachate treatment, focusing on its effectiveness in enhancing oxidation performance and mitigating membrane fouling. The results indicated that after DBD/Fe(VI) treatment, TOC and UV254 removal efficiencies increased by 44 % and 67 %, respectively. Additionally, the DBD/Fe(VI) system excelled in removing fluorescent substances and high molecular weight organic compounds, thereby reducing the formation of the cake layer on the nanofiltration membrane. This system enhanced oxidation performance through the synergistic production of reactive intermediates, with Fe(V)/Fe(IV) and •OH being the main active species, O2•-, and 1O2 also contributing significantly. The degradation pathway of perfluorooctanoic acid was investigated by utilizing it as the representative pollutant. Compared to the raw landfill leachate system, the DBD/Fe(VI) increased membrane flux by 104 %, while reducing reversible and irreversible fouling resistances by 67 % and 75 %, respectively. Furthermore, the advantages and practical application potential of the DBD/Fe(VI) system were evaluated from energy consumption, economic cost, and carbon dioxide emissions. The study offers an innovative method for landfill leachate treatment and fouling mitigation.

“A Review Of The Study Of Estimation Of The Concentration Of Particulate Matter Over Chhatrapati Sambhajinager (M.S) City Using Remote Sensing”

India’s ongoing population explosion has imposed a great strain on the country’s environment. This rapid growth in population along with urbanization and industrialization has placed lot of pressure on India’s infrastructure and natural sources. Forests destruction, soil erosion, water pollution and lowering of the level’s quality continue to hinder economic development in under developed and rural region of India. The rapid urbanization and subsequently industrialization in India leads degrading environmental condition in metro cities in India. Chhatrapati Sambhajinager cannot be an exception Chhatrapati Sambhajinager is one of the most affected cities where air particulate matters (PM) have been registered at the levels more than 10 times our country’s legal limit (Ninawe et-al 2010). Despite of introducing legal policy measures in India air pollution remained major concern. In many urban areas including Chhatrapati Sambhajinager, there is high level of pollution. This cause increase in the levels of air pollution including deforestation that is causing human health hazards. In India aggravation of air pollution is owing to the rapid and growth in the size of cities. The movement of people from one place to other helped to Increase in consumption pattern, unplanned urban and industrial development is the main causes of air pollution in big cities of India that resulted the worst. (Chitale et-al 2010). In India, the most severe problem of environment comes in varied forms including vehicular emissions and unsaturated industrial smoke. This has resulted in bringing about adverse effect on population and cities are unable to implement pertinent pollution control mechanism. High concentration of pollution in India is not due to absence of a sound environment legal regime, but is due to lack of environmental enforcement at the local level. Regulatory reforms aimed to improving the air pollution problem in most of the metro cities. To my knowledge this might be the first attempt in Maharashtra, to produce high-resolution of particulate matter and gaseous NO2 and SO2 pollution surface, making use of remote sensing data (Kourase et-al 2010). The outcome of this research work will be made available to help expose health research in this polluted and densely populated region

Exploring electrochemical mechanisms for clindamycin degradation targeted at the efficient treatment of contaminated water

Numerous studies reveal pollutants like clindamycin (CLD) in the environment, posing environmental and health risks. Conventional water treatment methods are ineffective at removing these contaminants, typically found in low concentrations. An innovative treatment approach is introduced through pre-concentration via adsorption, which is highly efficient, energy-saving, and reusable. The innovation uses solvents like methanol or ethanol to desorb pollutants, creating concentrated CLD solutions for more effective electrochemical degradation than conventional methods. Thus, this study explores, for the first time, the behavior of CLD electro-oxidation in different media—water, methanol, and ethanol—using a Dimensionally Stable Anode (DSA®-Cl₂). The study reveals distinct degradation mechanisms and offers new insights into solvent-assisted electrochemical treatments. After 30 min of electrolysis, all the current densities evaluated promoted significant degradation, ranging from 90 to 92%. The energy consumption was 2.9 Wh m⁻³ per percentage point at current densities of 2 and 3.5 mA cm⁻2. This demonstrates that using higher current densities over shorter electrolysis times is feasible, achieving removal rates of approximately 90%.The performance of chloride-based electrolytes was superior to that of sulfate-based electrolytes due to the ability of DSA®-Cl2 electrodes to generate reactive chlorine species more efficiently. A higher concentration of supporting electrolytes initially improved CLD removal, but no significant changes were observed after 1 h. Neutral pH conditions optimized CLD degradation, achieving up to 91% removal. Higher pollutant concentrations were associated with lower kinetic constants and decreased removal percentages. Methanol and ethanol enhanced removal rates to 98.3% and 92.3%, respectively, by generating oxidizing species such as methoxy, hydroxymethyl, and ethoxy radicals. The degradation by-products differed across the three media, with each solvent exhibiting distinct oxidation mechanisms. These findings highlight the potential of using methanol or ethanol as an electrolytic medium with efficiency comparable to water.

Mobile laboratory measurements of air pollutants in Baltimore, MD elucidate issues of environmental justice

ABSTRACT The City of Baltimore, MD has a history of problems with environmental justice (EJ), air pollution, and the urban heat island (UHI) effect. Current chemical transport models lack the resolution to simulate concentrations on the scale needed, about 100 m, to identify the neighborhoods with anomalously high air pollution levels. In this paper we introduce the capabilities of a mobile laboratory and an initial survey of several pollutants in Baltimore to identify which communities are exposed to disproportionate concentrations of air pollution and to which species. High concentrations of black carbon (BC) stood out at some locations – near major highways, downtown, and in the Curtis Bay neighborhood of Baltimore. Results from the mobile lab are confirmed with longer-term, low-cost monitoring. In Curtis Bay, higher concentrations of BC were measured along Pennington Ave. (mean [5th to 95th percentiles] = 2.08 [2.0–10.9] μg m−3) than along Curtis Ave. just ~ 150 m away (0.67[0.1 – 1.8] μg m−3). Other species, including criteria pollutants ozone (O3), carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), and fine particulate matter (PM2.5), showed little gradient. Observations with high spatial and temporal resolution help isolate the mechanisms leading to locally high pollutant concentrations. The difference in BC appears to result not from heavier truck traffic or slower dispersion but from the interruptions in traffic flow. Pennington Ave. has three stoplights while Curtis Ave. has none. As heavy-duty diesel-powered vehicles accelerate, they experience turbo-lag and the resulting rich air-fuel mixture exacerbates BC emissions. Immediate mediation might be achieved through smoother traffic flow, and the long-term solution through replacing heavy-duty trucks with electric vehicles. Implications: We present results documenting the locations within Baltimore of high concentrations of Black Carbon pollution and identify the likely source – diesel exhaust emissions exacerbated by stop-and-go traffic and associated turbo-lag. This suggests solutions (smoother traffic, retrofit particulate filters, replacement of diesel with electric vehicles) that would enhance Environmental Justice (EJ) and could be applied to other cities with EJ problems. Synopsis: This paper presents observations of atmospheric black carbon aerosol showing impacts on environmental justice, then identifies causes and suggests solutions.

Spatial variability of bacterial biofilm communities in a wastewater effluent-impacted suburban stream ecosystem.

Streams in arid and semi-arid biomes are often dependent on their flow from municipal sources, such as wastewater effluent. However, wastewater has been shown to contain high concentrations of nutrients and chemical pollutants that can potentially harm aquatic ecosystems and their biota. Understanding if and the type of microorganisms that respond to pollution sources, specifically effluent from wastewater treatment facilities, in regions where flow is predominantly from treatment facilities, is critical for developing a predictive monitoring approach for eutrophication or other ecological degradation states for freshwaters.

River quality management: Integrating uncertainty, failure probability, and assimilation capacity

Managing river water quality is challenging due to uncertainties in hydraulic and hydrologic parameters. This study integrates the symmetric exponential function (SEF) approach for solving the advection-dispersion equation with the Monte Carlo method in MATLAB. This combination allows us to explore the river's assimilation capacity and the failure probability (Pf) of maintaining desired water quality standards. Here, Pf represents the likelihood of pollutant concentrations exceeding acceptable limits under varying river conditions. A key contribution of this study is the introduction of a novel equation, developed using the Genetic Programming (GP) soft computing tool, to calculate assimilation capacity considering the failure probability of water quality provision. This equation provides a valuable tool for risk assessment in water resource management by quantifying pollutant assimilation dynamics. Its robustness is validated through high Coefficient of Determination (R2) and Overall Index (OI) values near 1, along with low Root Mean Square Error (RMSE) and Mean Absolute Error (MAE). The study identifies critical river characteristics, such as flow velocity and pollutant load, significantly influencing the reliability index (β). By outlining how adjustments in these parameters can achieve a target reliability index (β=4.526), our study offers a practical approach to safeguarding river ecosystems. For example, increasing flow velocity by 76 % can shift the river from a safe state (Pf=3×10−5) to a hazardous state (Pf=1), while a 44 % decrease in velocity allows for 57 % more pollutant assimilation. These findings highlight the importance of flow control as a cost-effective strategy for mitigating high pollutant concentrations and ensuring sustainable water quality management. By integrating numerical approaches with reliability sampling methods and soft computing techniques, this study enhances understanding of river system dynamics and supports informed decision-making for protecting water resources.

Periodate-driven efficient degradation of diverse pharmaceuticals with iodine-doped MnO2

This research investigated the development of a novel catalyst for contaminant remediation. The strategy involved enhancing the catalytic effectiveness of MnO2 by strategically incorporating iodine, resulting in I-MnO2. Electron paramagnetic resonance (EPR) spectroscopy confirmed an augmentation in oxygen vacancies upon iodine inclusion, leading to increased catalytic activity. I-MnO2 was evaluated as an efficient catalyst within an advanced oxidation process for ciprofloxacin removal through periodate activation. The system achieved a 91.2 % degradation of 20 ppm ciprofloxacin within 9 min, demonstrating a strong correlation between catalyst and oxidant dosages. The I-MnO2/IO4¯ system exhibited remarkable stability across a broad pH range and minimal susceptibility to ionic strength variations, water anions, and humic acid presence. Quenching experiments coupled with EPR analysis suggested the involvement of singlet oxygen (1O2) and iodate radicals (IO3•) generated from the interaction of the metastable Mn(IV)-O-IO3 species with ciprofloxacin. X-ray photoelectron spectroscopy analysis of Mn 2p and O 1s orbitals, performed before and after reactions, further corroborated the role of I-MnO2 in facilitating periodate activation by promoting the conversion of Mn(II) and Mn(III) to Mn(IV) species. This innovative catalyst demonstrates exceptional efficiency in eliminating high concentrations of organic pollutants, suggesting its potential for practical and cost-effective applications in wastewater treatment.

Dioxin-like and estrogenic activity screening in fractionated sediments from a German catchment after the 2021 extreme flood

BackgroundThe flood in July 2021 is considered one of the largest flood disasters in Western Europe in decades, with massive socio-economic consequences. The potential emission and remobilization of anthropogenic pollutants can lead to additional environmental consequences, which need to be addressed in long-term mitigation strategies. The Inde River and its tributary, the Vichtbach River, form a catchment located at the transition from the low mountain ranges of the Eifel to the lowlands of the Lower Rhine Embayment in Germany. The area has been an industrial and mining hotspot for centuries, making it a high-risk area for flood sediment pollution. The present study provides an ecotoxicological screening of flood sediments of the Vicht–Inde catchment to gain an impression of the degree of contamination by organic pollutants by means of in vitro effect-based method. Sediment samples were collected within days after the flood and fractionated prior to biotesting, and supportive instrumental geochemical analysis was performed.ResultsFlood sediments did not reveal estrogenic potential, which was included in the testing strategy as a relevant endpoint for industrial chemicals and untreated wastewater. In contrast, moderate-to-high dioxin-like activity was observed in 70% of the sediment samples with a peak dioxin-like potential at the restored section of the Inde. Overall, four hotspot samples were identified as at risk, which aligned mostly with the high concentration of organic pollutants including PAHs and PCBs. The fractionation allowed the identification of PAHs and their derivates as the most likely toxicity drivers for dioxin-like activity in the sediments of the Vicht–Inde catchment.ConclusionThe results provide first information on the prioritization of hotspot locations at risk for a detailed ecotoxicological profiling and a post-flood monitoring of organic contamination. The identified sinks of contamination in the floodplain areas can be considered a source for remobilization of pollution in future flood events, which is highly relevant for the receiving Rur River.

Highly efficient degradation of ethanol, acetaldehyde, and ethyl acetate removal by bio-trickling filter reactors with various fillers

This study investigates the purification performance of bio-trickling filters (BTFs) using different media to treat ethanol, acetaldehyde, and ethyl acetate in kitchen waste malodorous gases. The media compared included a custom composite medium, pine bark, hollow polyhedral spheres, and ceramic particles. Over 25 days, the composite medium outperformed the traditional media, achieving removal rates of 90.13 % for ethanol, 63.89 % for acetaldehyde, and 82.56 % for ethyl acetate during the biofilm initiation phase, with the others below 60 %. Even under low empty bed residence time and high inlet concentrations, the maximum elimination capacity for ethanol, acetaldehyde, and ethyl acetate was 8.34–14.70 g/m3·h, 9.55–15.06 g/m3·h, and 6.18–10.45 g/m3·h. Kinetic analysis showed the Michaelis-Menten model fit well, indicating enhanced removal potential. High-throughput of 16S rDNA sequencing identified dominant microorganisms like Enterobacteriaceae (13.89 %), Stenotrophomonas (29.23 %), and Acinetobacter (4.09 %) in the composite medium, which thrived even at high pollutant concentrations. Principal component analysis (PCA) demonstrated differences in the microbial composition of the custom composite medium compared to traditional media under varying inlet concentrations and loads. This study provides technical support for the treatment of complex malodorous gas mixtures.

Environmental and Health Impacts Resulting From Burning Solid Waste Near Residential Areas in Diyala Governorate, Iraq

General Background: Rapid development, population growth, and improper disposal of municipal solid waste are prevalent issues in developing countries, leading to significant environmental and health challenges. Specific Background: In Iraq’s Diyala Governorate, the absence of integrated waste management exacerbates pollution through waste burning and heavy metal contamination, posing risks to nearby residential areas. Knowledge Gap: While previous studies have addressed waste management in developing countries, there is limited research on how local waste disposal practices impact air, soil, and water quality in specific areas of Diyala. Aims: This study evaluates the air quality and levels of heavy metals in soil and water near five landfill sites in Diyala Governorate: Kanaan, Al-Khalis, Baladruz, Khanaqin, and Hamrin, aiming to assess the pollution levels and the potential health risks to nearby communities. Results: The findings reveal significant differences across the sites, with the highest pollutant concentrations in Kanaan for air (40±445.8), soil (22.18±35.64), and water (3.037±3.146), while Hamrin recorded the lowest concentrations. All sites demonstrated statistically significant differences (P < 0.05). Novelty: This study provides the first comprehensive analysis of the environmental impact of waste disposal practices in Diyala, linking pollutant concentrations with specific landfill sites. Implications: The results underscore the need for improved waste management strategies, including monitoring, waste sorting, and recycling initiatives, to mitigate the negative effects on public health and the environment, particularly in areas near waste dumps. Highlights: Pollution levels vary significantly across Diyala's landfill sites. Kanaan site has the highest air, soil, and water contamination. Better waste management is needed to reduce environmental and health risks. Keywords: Municipal waste, environmental pollution, heavy metals, Diyala Governorate, landfill impact

Feasibility of riverbank filtration in Vietnam

Riverbank filtration (RBF) could contribute to meeting the growing demand for drinking water in Vietnam. This study investigates the feasibility of implementing RBF in different regions of Vietnam, with a focus on the Red River Delta (RRD) and Binh Dinh (a province in central Vietnam). Although Vietnam’s extensive river network and shallow aquifers generally provide favorable hydrogeological conditions for RBF, regional variations in hydrogeology introduce specific challenges. In the RRD, complex hydrogeological settings, such as thick clay layers near the surface and low hydraulic conductivity in the Holocence aquifer, can limit the effectiveness of RBF in maximizing the portion of bank filtrate and improving water quality. In contrast, Binh Dinh generally presents more favorable conditions, with absence of clay layers on top and higher hydraulic conductivity leading to successful RBF implementation. Water quality issues such as high concentrations of ammonium, arsenic, and other pollutants persist in both RBF and groundwater in the RRD, requiring careful site-specific evaluations. The study also highlights that while surface water remains underutilized compared to groundwater, its use may be economically preferable in regions where groundwater quality is compromised. Lessons learned from the RRD and Binh Dinh can serve as good practice for RBF implementation in other parts of Vietnam. The findings indicate that while RBF holds significant promise for enhancing water supply in Vietnam, its application needs to be carefully tailored to local hydrogeological and water quality conditions.

Microbial community dynamics in different floc size aggregates during nitrogen removal process upgrading in a full-scale landfill leachate treatment plant

Upgrading processes to reduce biodegradable organic substance addition is crucial for treating landfill leachate with high pollutant concentrations, aiding carbon emission reduction. Aggregate size in activated sludge processes impacts pollutant removal and sludge/water separation. This study investigated microbial community succession and driving mechanisms in different floc-size aggregates during nitrogen removal progress upgrade from conventional to partial nitrification–denitrification in a full-scale landfill leachate treatment plant (LLTP) using 16S rRNA gene sequencing. The upgrade and floc sizes significantly influenced microbial diversity and composition. After upgrading, ammonia-oxidizing bacteria were enriched while nitrite-oxidizing bacteria suppressed in small flocs with homogeneity and high mass transfer efficiency. Larger flocs enriched Defluviicoccus, Thauera, and Truepera, while smaller flocs enriched Nitrosomonas, suggesting their potential as biomarkers. Multi-network analyses revealed microbial interactions. A deep learning model with convolutional neural networks predicted nitrogen removal efficiency. These findings guide optimizing LLTP processes and understanding microbial community dynamics based on floc size.

Screening of Characteristic Pollutants and Risk Pollutants in Different Media in the Yangtze River Basin Using Comprehensive Evaluation and Risk Quotient Methods

A variety of pollutants have frequently been detected in the Yangtze River Basin with the rapid economic development, the population increase, and the acceleration of urbanization, which threaten the aquatic ecosystem and human health. A multi-criteria comprehensive evaluation method was developed to identify the characteristic pollutants, and the risk quotient method was used to derive the risk pollutants in water and sediment samples in this article. A total of 155 pollutants from 11 categories were detected in the Yangtze River Basin according to the literature research. Then, the K-means method was used to analyze the cluster of pollutant comprehensive scores. All pollutants were graded based on their scores and recorded as Ⅰ-Ⅵ according to the number of cases in each cluster. A total of 43 pollutants with high scores of Ⅰ and Ⅱ were listed as the characteristic pollutants, which included 11 polycyclic aromatic hydrocarbons, 11 organochlorine pesticides, 10 polychlorinated biphenyls, eight dioxins, two heavy metals, and one phthalate ester. The top five median concentrations of contaminants in water and sediment samples were heavy metals, polycyclic aromatic hydrocarbons, phthalates esters, bisphenols, and pharmaceuticals and personal care products. According to the principle of risk maximization, the risk entropy value （RQ） was calculated based on the highest pollutant concentration. A total of 38 risky pollutants were screened in the water samples （RQ ≥ 0.1）. There were eight high-risk pollutants with RQ ≥ 1, which included benzo[a,h]-anthracene, anthracene, benzo[a]anthracene, pyrene, methoxychlor, aldrin, 2,4'-dichlorodiphenyl, and cadmium. There were 15 high-risk contaminants in the sediment, which included benzo[b]fluoranthene, anthracene, acenaphthene, fluoranthene, cadmium, lead, chromium, arsenic, selenium, dibutyl phthalate, dimethyl phthalate, diisobutyl phthalate, norfloxacin, perfluorobutyric acid, and bisphenol A. The risk pollutants contained emerging pollutants, which included ten pollutants in water samples and nine pollutants in sediments. Antibiotic pollutants accounted for the largest proportion of these emerging pollutants. The information provided in this article may be useful for the relevant departments to monitor the pollutants and propose management programs for the Yangtze River Basin. Additionally, it is of great significance for the ecological environmental protection and management of the Yangtze River Basin.