Comprehensive Pollution Research Articles

Effects of Different Remediation Treatments and Rice Intercropping on the Integrated Quality of Paddy Soils Mildly Contaminated by Cadmium and Copper

The issue of soil contamination by heavy metals (HMs) has attracted extensive attention. In the present study, the effects of four remediation measures combined with rice intercropping on the quality of soils were evaluated in a mildly HM-contaminated paddy field. The results showed that better comprehensive remediation effects were found in the intercropping system with high and low Cd-tolerant rice than in the monoculture system. Both foliar spraying of sodium selenite and inoculation with Pseudomonas TCd-1 significantly reduced the Nemerow comprehensive pollution index (NCPI) of the soils. The application of biochar and lime significantly increased the soil fertility index. Among all the treatments, the application of 30 t∙hm−2 biochar and 3600 kg∙hm−2 lime improved soil fertility the most. The lowest single-factor pollution indices (SFPIs) of Cd, Cu, Zn, Ni and Pb and the NCPI of the soils were observed in the treatment with foliar spraying of sodium selenite at 45 mg∙L−1, showing the greatest comprehensive reduction in soil HMs. The application of 1200 kg∙hm−2 lime and 30 t∙hm−2 biochar and foliar spraying of 45 mg∙L−1 sodium selenite effectively improved the soil quality. Overall, the soil quality of paddy fields dramatically influenced the cleaner production of rice and is of great significance to the maintenance of food security.

​Quantitative assessment of heavy metal concentrations, pollution levels, and sources apportionment in one of China's top 10 most livable cities.

Urban topsoil is not only an essential part of the urban ecosystem, but also a powerful carrier of pollutants in the urban environment. In this paper, 130 topsoil samples from urban area of Xinyang in central-eastern China were selected, the aim is to quantitatively investigate the concentrations, pollution levels, and sources apportionment of 8 heavy metals (HMs, encompassing arsenic (As), cobalt (Co), copper (Cu), chromium (Cr), lead (Pb), nickel (Ni), vanadium (V), and zinc (Zn)) via geochemical method. The main conclusions are as follows. (1) The eight HMs in the topsoil have been artificially enriched to varying degrees, which are lower than the street dust levels sampled in pairs. (2) Cu, Zn, and Pb were significantly contaminated, and As, Co, Ni, Cr, and V were relatively low levels of contamination. Overall, comprehensive pollution levels were particularly severe, with 30.0%, 39.2%, and 30.8% for slight, moderate, and serious pollution, respectively. (3) Co, Ni, V, and Cr predominantly originated from natural sources, the percentage contribution of which is 6.3%; Pb, As, Cu, and Zn were predominantly derived from traffic-derived sources, with a percentage contribution of 93.7%. Thus, the first-order source of HMs in the topsoil originates from traffic-induced activities, similar to the case of street dust. Our findings can be beneficial in providing local governments with a reference to formulate environmental pollution controls, and also provide a case study for environmental pollution control in the other livable cities in China.

Spatial Distribution, Pollution Assessment, and Source Analysis of Soil Heavy Metals Under Different Land Use Types in the Southern Area of Laizhou Bay

To ascertain the status of the surface soil heavy metal pollution in the southern area of Laizhou Bay, 263 surface soil samples were collected from seven different land use types in the study area and the contents and pH of eight soil heavy metals （As, Cr, Ni, Cu, Zn, Cd, Pb, and Hg） were determined. The pollution assessment was carried out using the geo-accumulation index method, Nemerow comprehensive index method, and potential ecological risk index method. Then, the source of heavy metal pollution was discussed using correlation analysis and the source analysis was carried out through positive matrix factorization （PMF）. The results showed that the surface soil in the study area was weakly alkaline； As, Ni, Zn, and Hg slightly exceeded the background values of Weifang and the spatial distribution of heavy metals showed a trend of low in the north and high in the south. The results of the geo-accumulation index indicated that the study area was pollution free and the geo-accumulation index of different land types was arranged in the order of As>Ni>Zn>Cr>Pb>Hg>Cu>Cd. The results of the Nemerow comprehensive pollution index indicated that the study area was lightly polluted and the Nemerow comprehensive pollution index of different land types was arranged in the order of town>grassland>forest>agricultural land>vegetable land>industrial land>mudflat. The results of the potential ecological risk index indicated that the study area belonged to low ecological risk and the potential ecological risk index of different land types was arranged in the order of agricultural land>town>forest land>grassland>vegetable land>industrial land>mudflat. The results of PMF analysis indicated that the heavy metal pollution sources in the study area mainly included natural sources, transportation sources, agricultural sources, and industrial sources, with contribution rates of 38.06%, 26.38%, 26.21%, and 9.35%, respectively.

Heavy metal characteristics and ecological threat assessment in water and sediments of Eniong Creek, Niger Delta, Nigeria

Heavy metal characteristics and ecological threat assessment in water and sediments of Eniong Creek, Nigeria was studied between August 2022 and January 2023 in 3 stations. Seven heavy metals were analyzed with standard methods and compared with quality Standard. Ecological threat was assessed in water using two metal pollution indices while six sediment quality assessment indices were used to access the sediment quality. Results showed that the mean concentrations of nickel, copper, cadmium and zinc in water sample exceeded the permissible limits set by National environmental (surface and groundwater) quality regulations for aquatic life, while copper and cadmium exceeded the permissible limits set by Canadian sediment standards quality for the protection of aquatic life in sediments in all the stations. The heavy metal pollution index (HPI) values exceeded the threshold (100) across the stations, ranging between 469.53 and 686.74 while comprehensive pollution index (CPI) ranged between 1.405 and 1.854, indicating moderate contaminated water. The sediment indices indicated that cadmium and copper were the major metallic pollutants. The indices indicated the following –contamination factor: copper (moderate) and cadmium (very high), degree of contamination (very high); ecological risk: cadmium and copper (high) while lead and zinc were moderate; potential ecological risk (high); quantification of contamination: cadmium and copper (anthropogenic); geo-accumulation index: cadmium (very highly polluted). The study revealed that the water body and sediments were polluted, attributed to anthropogenic activities.Keywords: Eniong Creek; Heavy Metals, Nigeria; Sediment; Water

Integrating spatial-temporal features into prediction tasks: A novel method for identifying the potential water pollution area in large river basins

Forecasting potential water pollution areas (PWPA) is essential for effective watershed management. However, there remains a limited understanding of the spatial-temporal features that influence water quality (WQ), and advanced technical methods for WQ forecasting. This study developed an integrated framework utilizing spatial-temporal graph convolution networks (STGCN) to enhance comprehension of the spatial-temporal features influencing WQ and to develop a practical module for integrating features into the WQ prediction. The Pearson correlation method and seasonal decomposition analysis described the WQ features. Subsequently, the spatial-temporal distribution of PWPA was assessed using both the comprehensive pollution index method and Cressman space interpolation technique. Data from 403 monitoring stations was collected from the Yangtze River basin (YZR), encompassing pollutants such as COD, TP and NH₄⁺-N. The finding revealed that maximum concentrations of COD (36.4 mg/L), TP (4.078 mg/L) and NH₄⁺-N (13.58 mg/L) exceeded the standard thresholds necessitating early warnings. A significant correlation among pollutants was observed with coefficients ranging from 0.356 to 0.475 (P < 0.001), indicating their potential utility in predicting PWPA. Seasonality components exhibited strong correlations with the original WQ (correlation coefficients ranging from 0.62 to 0.89), followed by residuals (from 0.37 to 0.61) and trend components (from 0.25 to 0.53). The geographic layout of WQ monitoring stations along river lines resembled a graph network structure, suggesting that watershed WQ prediction can be classified as a spatial-temporal prediction task. The STGCN model achieved R2 values ranging from 0.607 to 0.844 for each pollutant on the test datasets, surpassing traditional models such as RNN, LSTM, and GRU in predictive accuracy. PWPA occurrences were predominantly identified in the southwestern regions as well as within the middle and lower reaches of the YZR. These results validated that the developed framework is capable of forecasting PWPA in large-scale watersheds while supporting effective watershed management.

Anthropogenic and Natural Impacts on Surface Water Quality: The Consequences and Challenges at the Nexus of Waste Management Facilities, Industrial Zones, and Protected Areas

AbstractThe objective of this study was to evaluate the physicochemical characteristics of surface waters near an old landfill, to assess water quality using the Water Quality Index (WQI) and the Comprehensive Pollution Index (CPI), and to identify factors influencing surface water composition using multivariate statistical analysis. The analysis of temporal changes of 15 surface water parameters (pH, EC, Cl−, NH4+, SO42−, BOD5, CODCr, TOC, Zn, Cd, Pb, Cu, Cr, Hg, and PAH) was complemented by the investigation of surface water flow, ambient temperature, and precipitation. A twelve-year monitoring period was considered, focusing on monitoring sites located along a watercourse in the area of the Radiowo landfill (Poland). No significant correlations were found between precipitation and surface water quality parameters in the outflow direction. The results showed that the average WQI values ranged from 63.06 to 96.86, while the average CPI values ranged from 0.56 to 0.88, indicating good water quality or low pollution, respectively. The temperature had a greater influence on the physicochemical parameters than the precipitation, especially on the parameters of contamination by organic compound (correlations between temperature and BOD5, CODCr, and TOC of 0.40, 0.50, and 0.38, respectively). Significant correlations were observed between EC, Cl−, NH4, BOD5, CODCr, and TOC in the outflow direction of the landfill. In addition, surface water flow showed a significant moderate negative correlation with pH (r = -0.44) and a moderate positive correlation with Cu concentration (r = 0.47) downstream of the landfill. The analysis of surface water quality monitoring, coupled with the critical evaluation of global research, has made it possible to understand the variation in surface water quality and the factors that influence it. The study confirmed that given the complex nature of Municipal Solid Waste (MSW) landfills, understanding the dynamics and factors affecting water quality is essential for effective water protection and management and achieving the Sustainable Development Goals (SDGs).

Identification of priority factors for risk control of trace toxic elements in surface resuspended dust of university campuses

The surface resuspended dust (SRD) that accumulates trace toxic elements (TTEs) can be suspended in the atmosphere and can be transported to other areas, such as campuses, through airflow. The risks and sources of TTEs in university campus SRD have not been thoroughly explored, especially the priority factors for TTEs pollution and risk control in the SRD. Taking Xi’an as a case, this study quantitatively apportioned the sources of TTEs in the SRD of university campuses using positive matrix factorization method, evaluated the ecological and health risks of the specific-source TTEs in the SRD using Monte Carlo simulation method, and determined the priority factors for risk control of TTEs in the SRD. We found that the pollution of Zn, Pb, and Cu in the SRD was severe, with significantly high to very high enrichment levels. The comprehensive pollution of TTEs in the SRD was high to extremely high levels, with Pb and Zn as the main contributors. The four sources of TTEs identified in the SRD were traffic exhaust, traffic non-exhaust, mixed, and natural sources, accounting for 19.1%, 43.3%, 11.2%, and 26.3% of the total TTE concentrations, respectively. The ecological risk of TTEs was quite serious, mainly caused by traffic exhaust Pb. TTEs in the SRD had a certain cancer risk to college students, mainly contributed by traffic exhaust. Traffic exhaust source is the main factor that needs to be controlled.

Hydrochemical characteristics, cross-layer pollution and environmental health risk of groundwater system in coal mine area: a case study of Jiangzhuang coal mine.

Long-term coal mining activities have significantly disturbed the groundwater system, resulting in aquifer water characterized by high levels of Na+, SO42-, and total dissolved solid (TDS), posing environmental health risks. To investigate the disturbance effects of coal mining activities on the groundwater system and ascertain the goaf water (OGW) environmental impacts, this study focuses on the surface water (SW), major aquifers, and OGW of Jiaozhuang Coal Mine. Through ion analysis and self-organizing map (SOM) clustering, the study analyzes the hydrochemical characteristics of the aquifer water, summarizes the accumulation patterns of OGW, and evaluates water quality of irrigation and drinking using sodium adsorption ratio (SAR), sodium percentage (SSP), and comprehensive pollution index (F). The results show that the hydrochemical characteristics of the groundwater system are influenced by a combination of cation exchange, dissolution, and mixing processes, with deep aquifers exhibiting high Na+ and SO42- levels. The OGW mainly originates from the coal roof sandstone aquifers water (RSW) and 3rd limestone aquifer water (3LW). Additionally, the groundwater shows high alkalinity and salinity hazards, with irrigation water quality assessments falling into general and unsuitable water quality area. Moreover, the groundwater quality is below Class III standards, with the worst being Class V, rendering it unsuitable as a drinking water source. Untreated discharge of OGW to the surface can easily threaten human drinking water health. The study results are helpful in identifying and controlling groundwater pollution caused by coal mining, ensuring the safety and sustainable utilization of water resources in mining areas and surrounding regions.

Determination of priority control factors for risk management of heavy metal(loid)s in park dust in Mianyang City

In order to determine the priority control elements and sources of heavy metal(loid)s (HMs) pollution in park dust, this study collected dust samples from 25 parks in the urban area of Mianyang City and measured the contents of 10 HMs. Based on Monte Carlo simulation, the probabilistic pollution levels and ecological-health risks of HMs were assessed. We found that the average contents of Zn, Co, Pb, and Cr were much higher than their background values in local soil and were influenced by artificial activities. The pollution assessment found that 5 parks were moderately polluted. The comprehensive pollution of HMs in the dust was mainly caused by Zn and Cr, and industrial source was the main contributor to Zn and Cr pollution. The contribution of As, Co, and Pb to the comprehensive ecological risk was high, accounting for 54.6%. Co, Pb, and As were the priority control HMs of ecological risk, while mixed source and industrial source were the priority control sources. HMs presented potential carcinogenic health risks to both children and adults. The non-carcinogenic risk to adults was within safety level, while some parks showed non-carcinogenic risk to children, which should be paid attention to. The source-specific health risk assessment showed that Cr and As were the priority control HMs for human health, while mixed source and industrial source were the priority control sources.

Pollution risk assessment and spatial distribution of potentially hazardous elements in selenium-rich soils in the Menyuan Basin of the northeastern Tibetan Plateau

The scientific utilization of selenium (Se)-rich soils necessitates the evaluation of the contents of potentially hazardous elements (PHEs). The Menyuan Basin, a representative Se-rich region located on the northern periphery of the Qinghai–Tibet Plateau, was chosen as the research area. Pollution risk and spatial source analysis was conducted for eight PHEs (As, Cr, Cu, Pb, Zn, Cd, Ni and Hg) using 5297 topsoil samples and 480 deep-soil samples. The results show that more than 50% of the total area has a Se content &gt;0.24 mg kg –1 . According to both single and comprehensive pollution indices, there are extremely few sampling sites with PHEs at risk of contamination. Low ecological risk was seen in 93.34% of the topsoil samples. The results show that although the overall level of surface soil pollution in the study area may be deemed negligible, on the surface or in deeper layers, the concentration centres of As, Cr, Ni, Zn, Pb and other elements show consistency, indicating that underlying parent rocks are the primary source of these elements. The findings presented in this study establish a scientific foundation for the secure development and utilization of Se-rich soils.

A comprehensive assessment of gold leaching wastewater through pollution and water quality indices. Case study: Small scale extraction facilities in the department of Caldas—Colombia

This study introduced a comprehensive methodology (the Six-Indices method for Water Pollution Assessment) to evaluate the quality of gold leaching effluents. Sampling was conducted for 14 months in small-scale gold mining facilities in the department of Caldas, Colombia. 23 physicochemical parameters were selected based on environmental regulations, standards of use for agricultural purposes and WHO recommendations. They covered general characteristics of effluents and critical inputs of the leaching process. 15 (pH, COD, TSS, CN−, Cl−, SO42−, S2−, Cd, Zn, Cu, Cr, Fe, Ni, Ag, and Pb) of them exceeded permissible limits. Multivariate statistical analysis (Person's correlation and hierarchical clustering analysis) and six Wastewater Quality Indices (WWQIs: Arithmetic Weighted Water Quality Index, WAWQI, Synthetic Pollution Index, SPI, Index of Water Pollution, WPI, Comprehensive Pollution Index, CPI, Heavy Metal Pollution Index, HPI, and Degree of Pollution, Cd) were used to comprehensively assess the effluent contamination. Key pollutant interactions (hydrocarbons & fats and oils, Zn & CN−, Cu & Cl−, as well as CN− & COD & SO42−) were revealed guiding targeted mitigation strategies. CN− and heavy metals were the main pollutants, posing serious environmental risks due to their high levels. The calculated HPI value was above the critical level of 100, indicating that the artisanal gold leaching operations in the studied area could be hazardous to human health. This study provides a starting point for developing effective and sustainable strategies to manage wastewater in mining regions in Colombia and other areas with similar mining practices.

Spatial Distribution, Leaching Characteristics, and Ecological and Health Risk Assessment of Potential Toxic Elements in a Typical Open-Pit Iron Mine Along the Yangzi River

Potential toxic elements (PTEs) pollution in the soil of abandoned open-pit mines can lead to great ecological risk to the areas around the mining districts. This study selected a typical abandoned open-pit iron mine along the Yangzi River in southeast China to investigate the spatial distribution, leaching characteristics, and ecological and health risk of the soil PTEs (As, Pb, Cd, Ni, Cr, Cu, and Zn). Leaching tests and sequential extraction were applied to study the migration of PTEs under the condition of rainfall. Different risk assessment methods were used to analyze the pollution and ecological risk of PTEs. The contents of As and Cu exceeded the background value of the Chinese soil guideline, with average contents of 50.71 ± 1.59 and 197.47 ± 16.09, respectively. The leaching test and sequential extraction indicated that sites 8 and 9 posed the greatest risk of PTE migration. According to the map of the Nemerow integrated pollution index (NIPI), the pollution level of the middle bare area of the study area was the highest, and Cu possessed the highest pollution index (PI) of 3.92. The average geo-accumulation index (Igeo) of As and Cu was between 1 and 2, reaching the pollution level of moderately contaminated. The average potential ecological risk coefficient (Ei) of As was the highest, and the contributions of As, Cu, and Cd to the potential ecological risk of the whole study area were 46.7%, 29.7%, and 14.3%, respectively. The range of the hazard index (HI) and the range of the As carcinogenic risk (CRAs) of all the sampling sites for children were 1.30–3.94 and 2.19 × 10−4–7.20 × 10−4, and As accounted for more than 85% of the total noncarcinogenic risk, indicating that the comprehensive pollution of PTEs in the study area posed great carcinogenic and noncarcinogenic risks to children. This study can be a proper reference for the subsequent recovery methods and environmental management of the whole mining area.

Spatial distribution, ecological and human health risks of potentially toxic elements (PTEs) in river Ravi, Pakistan: A comprehensive study

Significant quantities of potentially toxic elements have been and are still being discharged into Pakistan's rivers through natural sources and anthropogenic activities. The present study provides a comprehensive study of potentially toxic element contamination in the water and sediment of the Ravi River, Pakistan. The research aims to examine the extent of pollution, its ecological risks, and the potential human health impacts through detailed geospatial analysis and statistical correlation. Water and sediment representative samples were taken and analyzed for potentially toxic elements, including Cobalt (Co), Cadmium (Cd), Zinc (Zn), Nickel (Ni), Arsenic (As), Chromium (Cr), Lead (Pb), Copper (Cu), and Manganese (Mn). Various pollution indices, such as the “Geo-accumulation Index (Igeo), Modified degree of Contamination (mCd), Nemerow comprehensive pollution index (Pt), Contamination factor (CF), Enrichment factor (EF), Pollution Load Index (PLI), and Potential Ecological Risk Index (PERI),” were calculated to determine the contamination levels and ecological risks. The results indicated significant spatial variability in metal concentrations, with higher levels observed in industrial and urban areas (near Lahore). Cd and As were identified as the most critical pollutants, exhibiting high Igeo, CF, EF, and PERI values. The PLI revealed that several regions along the river are heavily polluted. Pt shows high comprehensive pollution near Lahore and moderate to high pollution in surrounding areas. According to mCd, most of the study area, especially sampling points near Lahore, ranges between 8 and 16, indicating a high degree of pollution. The Human Health Risk (HHR) assessment, considering ingestion, inhalation, and dermal contact pathways, highlighted that children are particularly vulnerable, showing higher Hazard Quotient (HQ) and Hazard Index (HI) values for several metals. Correlation analysis revealed significant relationships between certain metals, suggesting common sources of contamination, likely from industrial discharges and urban runoff. The comprehensive mapping and statistical analysis underscore the urgent need for implementing effective pollution control measures to mitigate the risks posed by potentially toxic element contamination in the Ravi River. This study provides critical insights for policymakers and environmental managers to prioritize areas for remediation and to develop strategies to protect both ecological and human health in the region.

Assessment of the adaptive capacity of children and adolescents in environmentally challenging conditions

BACKGROUND: A number of recent studies have demonstrated an increase in the number of children and adolescents with deviations in physical development attributing this increase to the effects of environmental pollution. The ability of children and adolescents to adapt to their environment can serve as an indicator of their physical development in unfavorable environmental conditions. AIM: To assess the physical development and adaptive capacity of children and adolescents living in regions with varying degrees of anthropogenic impact on the environment. MATERIAL AND METHODS: An analysis of the environmental situation in the Ulyanovsk region was carried out based on the author’s own research of atmospheric air, drinking water and soil samples collected from residential areas in 2009–2023. The study focused on identifying pollutants in the natural environment and calculating a comprehensive pollution indicator for each environmental component. In addition, a survey of schoolchildren in the Ulyanovsk region was conducted. Height, weight, chest circumference, body mass index, heart rate, systolic and diastolic blood pressure were measured. The adaptation capacity (AC) of the study participants was calculated using the Baevsky formula. RESULTS: Schoolchildren of both genders, who lived in regions with low level of anthropogenic impact on the environment, had higher values for morphological and functional characteristics than schoolchildren in regions with high degree of anthropogenic impact. Median AC values for boys and girls in the latter group were higher than those in the former, suggesting heightened adaptation mechanisms in environmentally disadvantaged areas. The differences in AC among girls closely mirrored those observed in boys, albeit across fewer age-groups, potentially indicating greater adaptive reserves in the latter group. CONCLUSION: Our findings can be used for sanitary and hygienic monitoring, prevention of childhood morbidity and the development of environmental strategies to reduce the adverse effects of environmental factors on public health.

Ecological restoration amplifies riverine fish catch of Gudusia chapra (Hamilton, 1822): an impact study in the river Ganga using multivariate statistical tools and water quality indices.

Fish residing in the aquatic ecosystem are considered the best ecological indicator for monitoring environmental habitat. To evaluate the changes that occurred due to relative restoration in the ecological habitat, a study was conducted in the freshwater zone of the river Ganga between Buxar, Bihar, and Ballia, Uttar Pradesh, between July 2021 and July 2022. In the monitoring, the physico-chemical condition, as well as the food and feeding habits of the fish Gudusia chapra, were monitored with the help of various pollution evaluating indices, namely, the algal pollution index (API) for planktons, the comprehensive pollution index (CPI-WQI), and the National Sanitation Foundation Water Quality Indices (NSF-WQI) for water. The study showed that the relative restoration facilitated the amplification of the fish catch from 5.60 to 98.98% in two consecutive years. The reduction in the API (15 to 4) as well as CPI (0.80 to 0.72) during both years signified the reduction of the pollution status of the river in the region. The NSF-WQI also decreased from 88.27 to 79.27 from 2021 to 2022. The electivity index for the fish showed that fish preferred the groups Cyanobacteria, Rotifera, and Copepoda. The multivariate, as well as univariate analyses, revealed that the fish G. chapra is significantly influenced by multiple abiotic as well as biotic variables, among which the major contributors are riverine velocity, transparency, conductivity, pH, dissolved oxygen, total alkalinity, carbonate, bicarbonate, salinity, total hardness, calcium, silicate, and biochemical oxygen demand.

Pollution Assessment and Source Apportionment of Heavy Metals in the Surrounding Soil of Typical Mining Areas in Tongling, Anhui Province

To study the level of heavy metal pollution and ecological risks in the soil around typical mining areas in Tongling, a total of 150 soil samples were collected from the study area. The content characteristics of 10 elements, namely, As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, Fe, and Zn, in the soils were analyzed. Methods including enrichment factor, the geo-accumulation index, single-factor pollution index, Nemero comprehensive pollution index, and potential ecological risk index were used to evaluate the pollution status of heavy metals in the soil of the study area. The pollution sources of heavy metals in the soil were also analyzed using correlation analysis, cluster analysis, and principal component analysis. The results showed that except for Cr and Fe, the average contents of the other eight heavy metal elements were higher than the soil background values in the study area. Pb, Zn, As, Cu, and Cd had a high degree of variation and were significantly affected by external interference. The spatial distribution showed that both Cr and Ni showed a decreasing trend from the edge to the central region, whereas the other eight heavy metals showed a decreasing trend from the central region to the surrounding areas. The pollution level of Cd and Cu in the soil of the research area was relatively severe. The overall ecological risk was at a medium to low level. Cd and Hg were the main contributing factors. As, Cd, Cu, Fe, Mn, Pb, and Zn mainly came from agricultural, industrial, and transportation sources, whereas Cr and Ni were mainly from natural sources. However, the sources of Hg were relatively complex. The research results can provide a scientific basis for the prevention and control of soil heavy metal pollution in metal mining areas, as well as the remediation of mine pollution.

Offshore wind farm operation contributed to a slight improvement in seawater quality along the Jiangsu Coast, China

The rapid growth of offshore wind farms (OWFs) is driven by concerns for energy security and climate change mitigation. However, their impact on marine environments remains poorly understood due to limited research. This study analyzes the effects of an OWF along China's Jiangsu Coast on seawater quality using data from different development phases. Results show the major pollutants were different across phases. Heavy metal pollution reached alert levels during construction compared to the safe levels observed in the pre-construction and operational phases, mainly due to increases in Pb, Cd, and Hg concentrations. Eutrophication was mild throughout all periods but exhibited a continuous decrease, primarily attributed to reductions in PH and COD concentrations. As a result, the comprehensive pollution level during construction was increased, but it was improved to a clean level during the operational phase. Besides, significant variations were observed in the spatial distribution patterns of major pollutant indices across different scenarios. These changes may stem from a combination effect of land-based pollution, aquaculture, OWF-induced disturbances to atmosphere and hydrodynamics, OWF-related drain and leakage contamination, and marine management policies. Understanding these effects informs OWF optimization, rational wind resource utilization, and marine ecology protection.

Determination of contamination, source, and risk of potentially toxic metals in fine road dust in a karst region of Southwest China.

Understanding the pollution situation of potentially toxic metals (PTMs) in fine road dust (FRD) in emerging industrialized cities and identifying priority control factors is crucial for urban environmental management, resident health protection, and pollution control. This study conducted a comprehensive investigation on PTMs pollution in FRD in Zunyi, a representative emerging industrialized city in the karst region of southwestern China. The average contents of Ni, Cr, Mn, Cu, Zn, Ba, Pb, V, and Co in the FRD were 43.2, 127.0, 1232.1, 134.4, 506.6, 597.8, 76.1, 86.8, and 16.2mgkg-1, respectively, which were obviously higher than the corresponding background levels of the local soil except for V and Co. The comprehensive pollution level of the determined PTMs in the FRD was very high, primarily caused by Zn and Cu. The sources of PTMs in Zunyi FRD were traffic, industrial, construction, and natural sources, accounting for 38.0, 23.7, 21.9, and 16.4% of the total PTMs content, respectively. The PTMs in Zunyi FRD exhibited a low to moderate overall ecological risk level, mainly contributed by Cu and traffic source. The cancer risks of PTMs in Zunyi FRD were high for all populations. The non-carcinogenic risk of PTMs in Zunyi FRD was acceptable for adults, but cannot be ignored for children. According to the source-specific probabilistic health risk estimation results, the priority control source is industrial source and the priority control PTM is Cr. Local governments need to give more attention to the carcinogenic risks and health hazards posed by PTMs in the FRD.

Assessment and Prediction of Health and Agricultural Impact from Combined PM2.5 and O3 Pollution in China

Combined PM2.5 and O3 pollution in China has caused negative health impacts on residents and reduced crop yields. The quantitative assessment and prediction of these impacts could provide a scientific basis for policy development. This study assessed the nationwide premature mortality, health effects, and crop damage attributable to PM2.5 and O3 pollution in 2019, and projected the associated health and agricultural losses under a business-as-usual (BAU) scenario for 2025. The economic benefits of improving air quality under different policy scenarios, including the 14th Five-Year Plan (FFP), Secondary Standard Limit (SSL), and Primary Standard Limit (PSL), were also explored. The results showed PM2.5 pollution in 2019 resulted in 246,000 all-cause premature deaths and the economic health loss was RMB 196.509 billion. Similarly, O3 pollution caused 186,300 premature deaths and the economic health loss was RMB 155.807 billion. O3 pollution has led to a loss of 28.5241 million tonnes of crop production and an economic loss of RMB 62.268 billion. Compared with 2019, the avoidable premature deaths from PM2.5 under different scenarios in 2025 were 50,600, 43,000, and 200,300 cases, respectively, exceeding the number of avoided premature deaths from O3 pollution. Compared with the BAU, reducing PM2.5 under different scenarios could generate economic benefits of RMB 70.178 billion, RMB 60.916 billion, and RMB 229.268 billion. Furthermore, the FFP scenario outperformed the SSL in mitigating winter wheat production losses caused by O3 pollution. These results provide important scientific support for the development and evaluation of future comprehensive pollution control measures for PM2.5 and O3.

The new region demarcation framework for implementing the joint prevention and control of groundwater pollution: A case study in western of Bohai Bay, China

The joint groundwater pollution prevention and control (GPPC) strategy has been extensively implemented to address the coastal region groundwater pollution challenges in China. However, regional groundwater pollution control and treatment efficiency cannot achieve the expected results due to the lack of regional priority control orders and accurate restoration levels. Thus, this study developed a new region demarcation framework method for delineating GPPC zones, in tandem with a comprehensive pollution index method, the DRASTIC model, source apportionment. To validate the new methodological framework, a case study of groundwater pollution in Qinhuangdao, the western of Bohai Bay, China, was implemented to calculate pollution prevention and control zoning. In total, 340 groundwater samples from shallow aquifers with 9 target pollutants (NO3-, NO2-, NH4+, As, Cd, Cr, Cu, Pb, and Ni) were selected as the dataset for GPPC regionalization. The results showed that GPPC zoning further clarified the direction of groundwater pollution protection and management in Qinhuangdao. Compared to the traditional method, the new GPPC zoning better reflects groundwater mobility characteristics and pollution transport and enrichment patterns in terms of groundwater functional integrity and delineation. This new regional demarcation framework method contributes to providing support for the fine division of groundwater pollution zoning and precise pollution control for groundwater resource management in China.