Potential Pollution Research Articles

Characteristics, sources, and health risks of volatile organic compounds in different functional regions of Shenyang

The concentration of 56 volatile organic compounds (VOCs) in the ambient air of Shenyang was continuously monitored at four sites in 2021. The characteristics, sources, secondary pollution potential and health risks of VOCs in different functional regions of Shenyang were discussed. The results indicate that the concentration of VOCs in industrial regions was significantly higher than that in non-industrial regions, with a mean of 41.09 ± 69.82 parts per billion volumes (ppbv) compared to 19.99 ± 17.86 ppbv (commercial & residential region in urban fringe), 27.51 ± 28.81 ppbv (educational & scenic region) and 29.71 ± 23.97 ppbv (commercial & residential region in urban center). The positive matrix factorization (PMF) model was utilized to assign the sources of VOCs in Shenyang, and six factors were recognized: gasoline vehicles (34.8 %), diesel vehicles (28.3 %), combustion (11.4 %), biogenic emissions (9.7 %), industrial processes (8.2 %), and fuel evaporation (7.7 %). The results of the reactivity evaluation indicated that the ozone (O3) formation potential (OFP) was primarily influenced by industrial processes (29.2 %), diesel vehicles (25.7 %), biogenic emissions (17.0 %). These three factors were also the top three contributors to secondary organic aerosol formation potential (SOAP), accounting for 44.2 %, 9.4 % and 30.3 %, respectively. At the all four sites, the non-carcinogenic and carcinogenic risks of VOCs ranged from 1.6 × 10−2 to 3.8 × 10−2 and from 2.3 × 10−6 to 3.3 × 10−6, respectively. And the main risks can be attributed to emissions from industrial processes and gasoline vehicles. These findings suggested to strengthen the control of vehicle emissions throughout all regions in Shenyang and industrial processes emissions in industrial regions.

IoT ENBALED SMART AQUARIUM FOR MONITORING THROUGH SENSORS

The development of an IoT-enabled smart aquarium system offering real-time monitoring and automated control of crucial environmental parameters. The core of the system lies in the ESP8266 microcontroller, facilitating seamless internet connectivity and data processing. Water quality assessment is achieved through a turbidity sensor, detecting suspended particles indicative of potential pollution. Environmental conditions are monitored using a DHT11 sensor, providing data on both temperature and humidity – essential factors for maintaining a healthy habitat for specific fish species. For automated lighting control mimicking natural day/night cycles and preventing excessive algae growth, a Light-Dependent Resistor (LDR) is implemented. The LDR adjusts aquarium lighting based on ambient light levels. Finally, a relay module controls the operation of a water pump, ensuring optimal water circulation and distribution of nutrients throughout the aquarium. While an I2C LCD connected to an Arduino Nano provides local data visualization within the aquarium setup, the ESP8266 transmits sensor readings to a user-friendly platform accessible remotely through a mobile application or web interface. This allows for convenient real-time monitoring of water quality, temperature, humidity, and lighting conditions. The system can be further programmed to generate alerts when critical parameters deviate from the ideal range, enabling proactive user intervention to maintain a healthy environment. This project demonstrates the potential of IoT technology to create a more automated, efficient, and user-friendly system for maintaining a thriving aquatic ecosystem. KEYWORDS: IoT (Internet of Things), Smart Aquarium, ESP8266, Turbidity Sensor, DHT11 Sensor, LDR(Light-Dependent Resistor), Relay Module, Water Pump, I2C LCD, Arduino Nano, Real-Time Monitoring, Automated Control, Remote Access, Mobile Application, Web Interface, Water Quality, Temperature, Humidity, Light Control, Aquatic Environment.

Study on Hydrothermal Arsenic Fixation in H3AsO4-FeSO4-Na2SO4-H2O System

In this study, hydrothermal metallurgy technology was used to convert arsenic in the solution into a stable, dense, and granular arsenic-fixing mineral, scorodite (FeAsO4·2H2O), that is conducive to storage. The effect of Na+ on the precipitation rate of arsenic and iron, the phase composition, and the transformation of arsenic residue during the mineralization and arsenic precipitation of hydrothermal scorodite in the H3AsO4-FeSO4-Na2SO4-H2O system were studied. The results show that Fe3+ co-precipitates with As5+ to form scorodite (FeAsO4·2H2O). In the later stage of the reaction, Fe3+ and Na+ combine to precipitate in the form of sodium jarosite [NaFe3(SO4)2(OH)6]. Under the conditions of an initial Na+ concentration of 10 g/L, an arsenic concentration of 10 g/L, a molar ratio of iron to arsenic of 1.5, a pH of 1, a reaction temperature of 160 °C, a stirring speed of 500 r/min, a reaction time of 3 h, and an oxygen partial pressure of 0.6 MPa, the precipitation rates of arsenic and iron were 98.2% and 93.2%, respectively. The phase composition of the arsenic residue is mainly composed of large-grained polyhedral crystal scorodite, and a small amount of irregular, small-grained crystal sodium jarosite is dispersed in it. By controlling the initial molar ratio of iron to arsenic, the concentration of Na+, and prolonging the reaction time, the formation of the sodium jarosite phase can be inhibited, and the transformation of the sodium jarosite phase into the scorodite phase can be promoted, so as to realize the efficient precipitation of arsenic, reduce the amount of arsenic residue, ensure the stability of arsenic residue, and avoid potential environmental pollution risks.

Assessing water quality of the Saigon River under the impact of industrial wastewater incidents

The Saigon River, as its economic potential and clusters and industrial parks evolve, is threatened by a high potential for water pollution. The objective is to evaluate the water quality (BOD5 and COD) under the influence of industrial wastewater incidents in the Saigon River using MIKE 21FM model. The results of model calibration and validation have high reliability with NSE values larger than 0.65 for the flow simulation and percentage error values less than 25% for the water quality simulation. Subsequently, the study proceeds to develop hypothetical scenarios in case untreated wastewater from industrial parks is charged directly into the Saigon River with actual discharge volumes of 15,811 m3/day and 30,000 m3/day. The results indicated that when an incident occurs at a location 1.3 km upstream from the Hoa Phu pumping station with a discharge volume of 15,811 m3/day, that has the most consequential impact, in terms of time and concentration of water pollutants on the pumping station. Specifically, the water quality at the pumping station area experiences a remarkable decrease after one and three hours of incidents in the dry and rainy seasons, respectively. In general, the impacts of industrial wastewater incidents vary depending on their location. An incident beneath the Hoa Phu pumping station on the Saigon River is expected to have a faster impact on the raw water source during the dry season compared to the rainy season.

Emerging Risk of Microplastics on Health, Agriculture and Environment

Exposure to microplastics is unavoidable, and a vast amount of microplastics are traveling around the oceans. Microplastics are considered one of the major potential pollutants due to their exposure and interference with the health of humans, animals, aquatic species, agriculture, etc. Shockingly, the microplastic was also detected in the human placenta (fetal and amniochorial membranes), which could cause long-term effects on human health. The disposal of plastic into the oceans is the most happening process across the globe; thereby, microplastic pollution is evident, leading to a huge risk to marine species. Also, the accumulation of microplastics on soil or land leads to an increase in pH value, thereby affecting the surface water and soil-groundwater medium, eventually affecting plant and human health. At the same time, microplastics and their particles are found in milk, meat, and other edible items, which directly affects human health. The appearance of microplastic particles in insects, birds, animals, and even human blood indicates its adverse effect on the environment. This review has discussed the impact of microplastic on the health of humans, aquatic species, and agriculture.

Exploring the green and low-carbon development pathway for an energy-intensive industrial park in China

Energy-intensive industrial parks (IPs) with the distinct characteristics of high energy consumption, substantial greenhouse gas (GHG) emissions, and huge pollution, are facing enormous pressure to realize the synergistic mitigation of GHG and air pollutants. Exploring the green and low-carbon transformation of energy-intensive IPs is urgently required to achieve the dual strategies of “carbon peaking and carbon neutrality” and “Beautiful China”. Taking a typical energy-intensive industrial park (IP) in Henan Province—the Red Flag Cannel Industrial Park (RFCP) as the research object, an integrated evaluation framework including multi-objective optimization model alongside the synergistic mitigation potential of carbon and air pollutant emissions, was established in the energy-intensive IPs. Five scenarios were designed to quantify the GHG and air pollutant mitigation potential, while synergistic emission reduction control effects were evaluated under four measures of industrial structure adjustment, energy structure adjustment, energy efficiency improvement, and industrial symbiosis. The scenario analysis indicates that the integrated scenario (S4) shows the most significant emission reduction potential by 2030. Compared to the baseline scenario (S0), the GHG emission reduction is 11.66 Mt CO2eq (53% reduction rate), and the emission reduction rate of air pollutants ranges from 38% to 69% in S4. The findings indicate that industrial structure adjustment and energy structure adjustment are the primary measures for reducing GHG and air pollutants of IPs. Additionally, the evaluation of synergistic effect demonstrates that industrial structure adjustment shows the most significant synergistic effect on GHG and air pollutant by 2030. Finally, some policy recommendations regarding the transformation direction of energy-intensive IPs were proposed. This study will provide valuable references for the green and low-carbon development of energy-intensive IPs.

Evaluation of the effects of dust pollution on specific plant species near and around the marble mining site in Rajasthan, India.

Airborne particles (dust pollution) pose a significant threat to both human and plant populations. Plant leaves act as crucial biofilters, capturing significant amounts of air pollution; this characteristic offers a valuable tool to measure local pollution levels and assess individual plant species' ability to intercept and mitigate harmful dust particles. The present study was carried out to asses the effect of responses of various plant species to dust pollution near and around the marble mining site comprising residential site, highway area, and Central University of Rajasthan as control. The anticipated pollution index, air pollution tolerance index (APTI), dust absorption capacity, metal accumulation index (MAI), and biochemical factors were used to evaluate plant responses. Azadirachta indica A. Juss. demonstrated the highest (29.0) and Vachellia nilotica L. showed lowest (5.6) APTI, respectively. A. indica showed maximum MAI values in comparison to other plant species situated at residential site. Additionally, monitoring of particulate matter (PM10) observed to highest at highway, followed by mining, residential, and control sites. Overall A. indica representing highest APTI and effective dust capturing capacity at all sites could serve as potential pollution sinks. V. nilotica, with its very low APTI, can be marked as biomonitoring tool for detecting dust pollution.

Influence of ongoing discharge from multiple wastewater treatment plants on microplastic patterns in small-scale receiving rivers

As widely acknowledged, wastewater treatment plants (WWTPs) stand as significant contributors to the presence of microplastics in surface water. Nonetheless, there exists a notable research gap regarding the extent of potential pollution resulting from the concurrent and uninterrupted discharges originating from multiple WWTPs into small-scale receiving water bodies. This study endeavors to address this knowledge deficit by conducting a thorough investigation into the prevalence of microplastics in surface water. The research encompasses seven distinct locations within the Changzhou section of the Beijing-Hangzhou Grand Canal and the effluent of three WWTPs situated along the tributary. The results indicate differences in the distribution of microplastics in surface waters of mainstream and tributaries. While the microplastic abundance and composition showed little variation along the main stream, the tributaries displayed an overall increasing trend in microplastic abundance from upstream to downstream. Notably, the major contributors to this increase were fragments, fiber particles, and microplastics with particle sizes ranging from 100 to 300 μm. Considering that the primary distinction between the tributaries and the mainstream is the presence of the three WWTPs along the tributaries, the study conducted a correlation analysis between river surface water and effluents from these plants. The results indicated a stronger correlation between the tributaries and the effluents, suggesting that WWTPs are one of the primary factors contributing to the elevated levels of microplastics in the tributaries. Finally, a comparative analysis of microplastic abundance in the Beijing-Hangzhou Grand Canal's Changzhou section and other regions was conducted. The findings revealed that the microplastic pollution level in the Beijing-Hangzhou Grand Canal's Changzhou section is higher than that in most other rivers. Therefore, the issue of microplastic pollution in the Beijing-Hangzhou Grand Canal's Changzhou section warrants our attention, particularly with regard to the effectiveness of microplastic removal by the WWTPs along its course.

Life cycle assessment of sewage sludge treatment: Comparison of pyrolysis with traditional methods in two Swedish municipalities

To achieve a closed nutrient cycle and more sustainable food production, enhanced nutrient recycling in the agri-food system is a necessity. Pyrolysis is an emerging technology to recycle the nutrient content of sewage sludge. The produced biochar can be used to reduce the need for mineral fertilizers; in addition, pyrolysis can also handle potential pollutants such as microplastics and pathogens present in sewage sludge. In this research, a life cycle assessment (LCA) was carried out to determine the environmental impact of sewage sludge pyrolysis as an alternative to current practices of two different cases of sewage sludge treatment in two municipalities in Sweden. The results indicated that avoiding mineral fertilizer production by using biochar has a significant influence on the environmental benefits. Furthermore, it showed that an integrated system of anaerobic digestion followed by pyrolysis could perform as the most environmental-friendly option for sewage sludge treatment with a lower risk of transferring pollution to the soil.

Assessment of water quality and heavy metal contamination in ballast water: Implications for marine ecosystems and human health

The global menace of non-compliance with ballast water management poses a pressing environmental threat, as it facilitates the transfer of harmful organisms and sediment contaminants. This study investigates the environmental impact of ballast water discharged by ships, focusing on water quality and heavy metal concentrations. The release of ballast water, often containing elevated levels of heavy metals like mercury, lead, and cadmium, poses a significant threat to marine ecosystems. The research, involving water sample collection from ten different vessels across various countries, assesses physicochemical parameters and heavy metal concentrations. Results indicate variations in temperature, turbidity, conductivity, dissolved oxygen, and pH levels among samples. Turbidity values surpassing WHO limits suggest potential anthropogenic pollution. The study identifies significant differences in pH values, potentially influencing microbial populations. Total dissolved solids and total suspended solids values vary, affecting the distribution of potential pathogens. The results reveal varying total concentrations of heavy metals (mg/L) in the following decreasing order: SA>SE>SF>SB>SC>SD>SH>SI>SG>SJ(6.07 >4.95 > 2.07 > 1.59>0.24>1.22>0.09>0.04>0.03>0.01). The highest concentration of heavy metals is recorded for iron (SA= 5.78), zinc (mg/L) (SB = 1.36, SE = 1.30, and SF = 1.35) and lead (Pb) (SE = 2.39). The elevated iron levels in vessels from SA are potentially linked to corrosion processes. Cadmium, lead, and nickel were not detected, except for lead in the sample from SE. Copper concentrations were aligned with EU standards in the vessels. Proper ballast water management is vital for monitoring water qualities, preventing environmental spread of heavy metals, ensuring marine ecosystem health, and developing compliance strategies for ships docking in ports. Highlights Global shipping causes heavy metal pollution, affecting human and ecosystem health Physicochemical parameters variations suggest potential pollution and microbial impact Mercury, lead, and cadmium in ballast water (BW) pose threats to marine ecosystems Increased iron levels could be associated with corrosion processes Effective BW management is crucial for environmental conservation

A Mini Review on Sewage Sludge and Red Mud Recycling for Thermal Energy Storage

Sewage sludge and red mud, as common industrial waste, have become a research hotspot in the field of achieving carbon peaking and carbon neutrality, reducing carbon emissions, and solving environmental problems. However, their treatment and disposal have always been a difficult problem in the environmental field. Utilizing these two materials for thermal energy storage can not only improve energy utilization efficiency but also further reduce carbon emissions during their treatment process, providing a new approach for sustainable development in the industrial sector. This article summarizes the research progress for the resource recovery of sewage sludge and red mud for direct thermal energy recovery and composite phase change energy storage. After proper treatment, sludge and red mud can be directly used as energy storage materials. In addition, sludge and red mud can be combined with phase change materials to prepare composite materials with an excellent energy storage performance. This composite has broad application prospects in fields such as solar energy utilization and building energy efficiency. However, there are still some challenges and issues in this resource recovery and utilization, such as potential environmental pollution during the treatment process, the long-term stability of energy storage materials, and cost-effectiveness, which require further research and resolution. The purpose of this paper is to evaluate the potential of sewage sludge and red mud as energy storage materials, to explore their feasibility and advantages in practical applications, and to reveal the research progress, technical challenges, and future development directions of these two materials in the field of thermal energy storage.

MAX-DOAS observations of pollutant distribution and transboundary transport in typical regions of China

Studying the spatiotemporal distribution and transboundary transport of aerosols, NO2, SO2, and HCHO in typical regions is crucial for understanding regional pollution causes. In a 2-year study using multi-axis differential optical absorption spectroscopy in Qingdao, Shanghai, Xi'an, and Kunming, we investigated pollutant distribution and transport across Eastern China-Ocean, Tibetan Plateau-Central and Eastern China, and China-Southeast Asia interfaces. First, pollutant distribution was analyzed. Kunming, frequently clouded and misty, exhibited consistently high aerosol optical depth throughout the year. In Qingdao and Shanghai, NO2 and SO2, as well as SO2 in Xi'an, increased in winter. Elevated HCHO in summer in Shanghai and Xi'an, especially Xi'an, suggests potential ozone pollution issues. Subsequently, pollutant transportation across interfaces was studied. At the Eastern China-Ocean interface, the gas transport flux was the largest among other interfaces, with the outflux exceeding the influx, especially in winter and spring. The input of pollutants from the Tibetan Plateau to central-eastern China was larger than the output in winter and spring, with SO2 having the highest transport flux in winter. The pollution input from Southeast Asia to China significantly exceeded the output, with spring and winter inputs being 3.22 and 3.03 times the output, respectively. Lastly, the transportation characteristics of a pollution event at Kunming were studied. During this period, pollutants were transported from west to east, with the maximum SO2 transport flux at an altitude of 2.87 km equaling 27.74 µg/(m2·s). It is speculated that this pollution was caused by the transport from Southeast Asian countries to Kunming.

Environmental impacts of COVID–19 responses on passenger vehicle transport scenarios: A life cycle approach

COVID–19 has disrupted human life considerably since the beginning of 2020. The transport sector is one of the most affected sector due to restrictions imposed to curb COVID–19 pandemic. This paper evaluates the environmental impacts of COVID–19 response scenarios using life cycle assessment approach. Six regions selected for the study are Australia, China, European Union (EU), India, United Kingdom (UK), and United States of America (USA). Data for vehicle population, vehicle kilometers travelled, fleet type, and fuel efficiency were used for 2015–2020. The environmental impacts were calculated for five scenarios; Baseline–2019, Business As Usual (BAU) and COVID–19 Response Scenario (CRS) for 2020 and 2030 namely, 2020–BAU, 2020–CRS, 2030–BAU, and 2030–CRS. The results indicate that COVID–19 occurrence and related response measures did not contribute to significant environment benefits in terms of Global Warming Potential (GWP) and other pollutants in short term and long term. This implies that although immediate reductions in emissions were observed in many studies, the long term effects were minimal due to irregular policies and unmanaged demand. Further, to achieve environment benefits sustained measures should be implemented in long term with proper planning and supporting infrastructure. Although electric vehicle strategies will provide benefits; emphasis on vehicle production and fuel production technologies is also needed to achieve the emission reduction targets. The findings are relevant for policy makers while devising policies to achieve the targets.

Tracing toxic path of antimony: From bioaccumulation to DNA hypomethylation in zebrafish (Danio rerio)

The increasing concentration of Antimony (Sb) in ecological environments has raised serious concerns about its potential biotoxicological impact. This study investigated the toxicokinetics, Global DNA Methylation (GDM), biomarker expression, and Integrated Biological Response (IBR) of Sb at different concentrations in zebrafish. The toxic mechanism of Sb exposure was simulated using molecular dynamics (MD). The results showed that significant differences effect existed (BCFk: liver > ovary > gut > brain) and uptake saturation phenomenon of Sb among zebrafish tissues. Over a 54-day exposure period, the liver emerged as the main target site for Sb-induced GDM, and the restoration was slower than in other tissues during the 54-day recovery period. Moreover, the concentration of Sb had a significant impact on the normally expression of biomarkers, with GSTM1 inhibited and MTF2, MT1, TET3, and p53 showing varying degrees of activation at different Sb concentrations. This could be attributed to Sb3+ potentially occupying the active site or tightly binding to the deep cavity of these genes. The IBR and MD results highlighted DNMT1 as the most sensitive biomarker among those assessed. This heightened sensitivity can be attributed to the stable binding of Sb3+ to DNMT1, resulting in alterations in the conformation of DNMT1's catalytic domain and inhibition of its activity. Consequently, this disruption leads to damage to the integrity of GDM. The study suggests that DNA methylation could serve as a valuable biomarker for assessing the ecotoxicological impact of Sb exposure. It contributes to a better understanding of the toxicity mechanisms in aquatic environments caused potential pollutants.

PH-modulated oxidation of organic pollutants for water decontamination: A deep insight into reactivity and oxidation pathway

Solution pH is one of the primary factors affecting the efficiency of water decontamination. Although the influence of pH on oxidants activation, catalyst activity, and reactive oxygen species have been widely explored, there is still a scarcity of systemic studies on the changes in the oxidation behavior of organic pollutants at different pH levels. Herein, we report the influence laws of pH on the forms, reactivities, active sites, degradation pathways, and products toxicities of organic pollutants. Changes in pH cause the protonation or deprotonation of organic pollutants and further affect their forms and chemistry (e.g., electrostatic force, hydrophobicity, and oxidation potential). The oxidation potential of organic pollutants follows the order: protonated form > pristine form > deprotonated form. Moreover, protonation or deprotonation can modify the active sites and degradation pathways of organic pollutants, wherein deprotonation renders them more susceptible to electrophilic attack, while protonation reduces their activity against electrophilic and nucleophilic attacks. Additionally, pH adjustments can modify the degradation pathway and the toxicity of transformation products. Overall, pH changes can affect the oxidation fate of organic pollutants by altering their structure, which distinguishes it from the effect of pH on oxidants or oxidant activation processes.

Microplastics, physical-chemical and biological principles of this environmental liability

The advent of plastic to the social situation has suppressed a series of demands from both the industry and the population, due to cost, durability and disposal. Because they can be rigid, malleable, opaque, translucent, easy or difficult to melt by the action of fire, some make them capable of serving as raw material for various products on the market, including those widely used in the food industry. In view of the above, the present study aims at a bibliographical review on the topic of microplastics, where the search will be to verify the primary and secondary steps necessary for the formation of the compound, its direct and indirect influence on food production, the physical-chemical processes through which compounds are obtained and the presence or absence of regulation regarding this environmental liability. The present study aims to analyze as a basis the search for knowledge of the primary and secondary formation of microplastics. Subsequently, together with its main objective, this study aims to search for the physico-chemical and thermodynamic phenomena involved in the process of formation and obtaining of microplastics, the polluting potential and, like all waste, its implications for human health. A study horizon was established covering the years 2015 to 2023, where 3,750 articles were found and after applying open access filters, duplication of publication, words present only in the abstract and not in the text, 49 articles remained that are the object of this study. The direct implications of microplastic pollution are already a relevant reason for discussion and subsequent regulation by managers, researchers, international organizations and society in general. Public health problems that can transform into microplastics, containment and adsorption mechanisms of these compounds in living organisms, are points to be pursued by academia as a whole. Contamination by these compounds was found in bottled mineral water, human milk, processed foods, seafood, showing the extent of contamination of this material.

Inner Sphere Adsorption Mechanisms for Arsenate and Lead on Goethite: Theoretical Implications in Contaminated Soil Recovery

ABSTRACT Studies that do not separate the adsorption of toxic elements and compounds by outer and inner spheres can lose precision regarding the potential pollution of the water table. We sought to establish details of inner sphere adsorption (ISA) mechanisms of arsenate (H2AsO4 −) and lead (Pb2+) on synthetic goethite under different experimental conditions: pH 5.0 and 9.0; purified and unpurified samples; different contact times (24 and 240 hours). Goethite (Gt) was saturated separately with Pb and arsenate (noncompetitive adsorption) and the outer sphere forms was previously removed. The ISA of Pb (maximum of 67,682 mg kg−1) was more intense than that of As (maximum of 4,492 mg kg−1). ISA of arsenate on goethite was dependent on the contact time and was more intense in acidic soils due to the greater possibility of the occurrence of biprotonated ferrol groups (Fe-OH2 +0.5) on goethite surface. The high negative charge density at the surface of the H2AsO4 − tetrahedron favored its ISA. On the other hand, the lower the level of ISA, the greater binding energy on goethite or adsorption stability of H2AsO4 −. The highest ISA of Pb occurred at the highest pH, when the hydroxylated species PbOH+ preferentially binds to oxygen from the deprotonated ferrol group (Fe-O−1.5), without the need for ligand exchange. The proposal mechanisms of inner sphere adsorption allow better understanding of the recovery actions of contaminated soils rich in Fe and Al oxides.

Morphological distribution and risk assessment of soil heavy metals in the Belly of the Three Gorges Reservoir area in Chongqing-A Case Study of Fengdu

The study of the morphological distribution and pollution risk of heavy metals in the hinterland of the Three Gorges Reservoir area in Chongqing can be used to provide data support for soil pollution prevention and control, ecological environment safety risk control and agricultural healthy development in the region. In this paper, Fengdu County, the hinterland of the Three Gorges Reservoir Area in Chongqing, was taken as the study area. The total amount and morphology of 8 heavy metal elements in the surface soil of agricultural land were analyzed and determined. The geocumulative index method was used to evaluate the pollution degree. The risk assessment coding method is used to evaluate the potential risk level. The results showed that the average contents of heavy metal elements As, Hg, Cu and Cr in the soil in the study area were relatively low. The average contents of Cd, Zn, Pb and Ni were higher than those in the Three Gorges Reservoir area. The mean value of Cd content was 1.71 times that of the background value. Cd in the soil heavy metal form is dominated by ion exchange state. The proportion of carbonate-bound state and iron-manganese bound state is relatively high. The proportion of bioavailable state was 46.36%, and the biological activity was strong. The other elements are mainly in the stable residue state. The results of the geoaccumulation index method showed that Cd was mainly mild pollution level. The other elements are mainly clean and pollution-free levels. The evaluation results of the risk assessment coding method showed that the risk of Cd contamination was the highest, and the risk of contamination of other elements was relatively low. On the whole, there is a certain degree of potential pollution risk in the soil Cd in the study area. Attention needs to be paid to the prevention and control of Cd.

Long term trends in global air pollution potential and its application to ventilation corridors

Long term trends in global air pollution potential and its application to ventilation corridors

Sustainable Solutions: Reviewing the Future of Textile Dye Contaminant Removal with Emerging Biological Treatments

Synthetic dyes, exceeding 100,000 types on the market and produced at a global scale of over 700,000 tons annually, are extensively used in the textile industry. This industry, a leading contributor to water contamination, relies on dyes like reactive, azo, anthraquinone, and triphenylmethane, resulting in substantial water usage and significant effluent generation. A significant modern challenge is the pollution caused by dye-mixed wastewater, releasing hazardous chemicals into water bodies and posing threats to ecosystems, plants, and human health. Traditionally, physicochemical techniques have addressed textile dye-containing wastewater, but their drawbacks, including cost, inefficiency, and potential secondary pollution, have steered attention towards biological alternatives. Utilizing microorganisms and enzymes, these biological methods, such as microbial cell enzyme immobilization, the biofilm technique, bioreactors, biofuel/bioelectricity production, and genetic engineering, have emerged as promising, cost-effective, and environmentally friendly solutions for efficient dye removal from wastewater. This review paper specifically highlights advanced biological techniques and emphasizes their efficacy in addressing the challenges posed by synthetic textile dyes. Through a systematic review of recent research papers, published results, and observations, this review paper provides insights into emerging biological treatment strategies for effectively removing synthetic textile dyes and contaminants from wastewater.