Pollution Index Research Articles

Analysis and probabilistic health risk assessment of vertical heavy metal pollution in the water environment of reservoir in the west coast new area of Qingdao, China

The West Coast New Area is a typical city in China where water supply is predominantly sourced from reservoirs. Heavy metal pollution in these reservoirs directly impacts the safety of drinking water and human health. Therefore, this study comprehensively evaluated the status of heavy metal pollution in the water environment and sediment of the main water supply reservoir in the study area, revealing the interaction relationship and pollution sources, as well as assessing the probabilistic health risks to human beings. The results show that there are different degrees of pollution in the main water supply reservoirs in the study area, and the pollution increases with the increase of water depth. The heavy metal pollution index was up to 2681, indicating heavily pollution. The main polluting elements were Mn and Fe, and the maximum contents were 4.11 mg L−1 and 0.68 mg L−1, respectively, which far exceeded the Class III standard limit of drinking water in China. The main source of pollution is human activities, and Mn release from sediment aggravates deep water pollution. The non-carcinogenic risk index of heavy metals in the reservoir, ranging from 4% to 14%, is higher than 1, indicating a potential non-carcinogenic threat. Furthermore, heavy metals have a much greater impact on children compared to adults, among which Mn is the main contributor to human non-carcinogenic risk, contributing more than 60%. Therefore, controlling the content of Mn and Fe can effectively reduce the heavy metal pollution of reservoir and human health risk. The research results are of great significance for the utilization of reservoir water resources and the protection of the ecological environment in the study area.

Source-specific probabilistic health risk assessment of dust PAHs in urban parks based on positive matrix factorization and Monte Carlo simulation.

Understanding the health risks of polycyclic aromatic hydrocarbons (PAHs) in dust from city parks and prioritizing sources for control are essential for public health and pollution management. The combination of Source-specific and Monte Carlo not only reduces management costs, but also improves the accuracy of assessments. To evaluate the sources of PAHs in urban park dust and the possible health risks caused by different sources, dust samples from 13 popular parks in Kaifeng City were analyzed for PAHs using gas chromatograph-mass spectrometer (GC-MS). The results showed that the surface dust PAH content in the study area ranged from 332.34µg·kg-1 to 7823.03µg·kg-1, with a mean value of 1756.59µg·kg-1. Nemerow Composite Pollution Index in the study area ranged from 0.32 to 14.41, with a mean of 2.24, indicating that the overall pollution warrants attention. Four pollution sources were identified using the positive matrix factorization (PMF) model: transportation source, transportation-coal and biomass combustion source, coke oven emission source, and petroleum source, with contributions of 33.74%, 25.59%, 22.14%, and 18.54%, respectively. The Monte Carlo cancer risk simulation results indicated that park dust PAHs pose a potential cancer risk to all three populations (children, adult male and adult female). Additionally, the cancer risk for children was generally higher than that for adult males and females, with transportation sources being the main contributor to the carcinogenic risk. Lastly, sensitivity analyses results showed that the toxic equivalent concentration (CS) is the parameter contributing the most to carcinogenic risk, followed by Exposure duration (ED).

Determination of Heavy Metal Concentrations at Ewu-Elepe, Ikorodu Dumpsite, Lagos, Nigeria

Heavy metal contamination of soil at dumpsites poses risks and hazards to humans and the ecosystems through inhalation of dust particles or dermal contact with the contaminated soil. Dumpsites are usually located at the outskirts of residential areas, but due to population increase in the urban centers as result of rural-urban movement which has become living habitats without considering the health implications. Thus, Ewu-Elepe dumpsite, located on the outskirts of Ikorodu, Lagos may pose a serious threat to residents of this area due to the improper disposal and ineffective management of waste at the dumpsite also, due to the metalic health issue recorded in this area. Therefore, this study was designed to determine the Heavy Metal Concentrations (HMC) and identify the type of Key Environmental Indicators (KEIs) responsible for the heavy metal contamination at the dumpsite. The Principal Component Analysis (PCA), Nemerow Integrated Pollution Index (NIPI), and Pollution Index (PI) procedures were adopted. The Akaike Information Criteria (AIC) was employed to determine the best KEI responsible for the presence of a particular heavy metal on the dumpsite. The Heavy Metals (HMs) found on the dumpsite were Zinc, Copper, Lead, Cadmium, Calcium, Manganese, and Iron. The identified KEIs on the dumpsite were: potential Hydrogen (pH), Electrical Conductivity (EC), Total Organic Carbon (TOC), Total Nitrogen (TN), Phosphorous (P), and Carbon Exchange Capacity (CEC). The AIC at 5% showed that the most significant KEI responsible for Zn was EC with the least value (16.21), pH for Pb (26.70), P for Ca (20.71), TOC for Cu (24.61) and Mn (81.09), TN for Cd (44.97), and CEC for Fe (41.04). The PCA and NIPI estimates for the heavy metals across the 20 sample points were (1760.57, 3.00); (1825.85, 2.30); (1330.80, 2.60); (1644.68, 2.40); (1602.57, 9.70); (1469.93, 2.40); (1379.85, 3.20); (1872.82, 2.40); (1859.30, 8.40); (1397.56, 2.30); (1995.32, 4.70); (1518.62, 3.10); (1565.33, 1.80); (1332.29, 5.10); (1748.59, 2.50); (1664.70, 3.90); (1792.24, 4.10); (1801.79, 2.30); (1801.18, 2.30); (1743.27, 2.00), respectively, implying that the dumpsite was highly concentrated in HMs. Copper, lead, cadmium, calcium, manganese, and iron highly polluted Ewu-Elepe dumpsite with potential hydrogen, electrical conductivity, total organic carbon, total nitrogen, phosphorous, and carbon exchange capacity as the key environmental indicators for the heavy metals.

Health Risk of Heavy Metals in Drinking Water Sources of Water-Carrying Lakes Affected by Retreating Polder: A Case Study of Luoma Lake

Heavy metal pollution is a critical issue affecting the safety of drinking water sources. However, the impact of human activities on heavy metal risk levels in water-carrying lakes remains unclear. This study aims to explore the risk mechanisms of heavy metals in Luoma Lake, an important water-carrying lake for the South-to-North Water Diversion Project. We explored the spatial and temporal differences in the distribution of heavy metals in Lake Luoma using methods such as the heavy metal pollution index (HPI) and assessed the risk variations using a health assessment model. The results indicated that heavy metal concentrations in water-carrying lakes generally decreased during the dry season, with Mn and Zn levels decreasing by 89.3% and 56.2%, respectively. The comprehensive score of HPI decreased by 13.16% following the retreating polder compared to the control area (Non-retreating polder area). Furthermore, the HPI at the drinking water intake was lower, which is closely associated with the elevated dissolved oxygen (DO) and oxidation–reduction potential (ORP) resulting from water diversion. The annual average health risk across the entire lake was not significant, with higher levels observed in the control area. The annual non-carcinogenic risk levels of Mn, Ni, Cu, Zn, and Pb range from 10−13 to 10−9, which are considered negligible risk levels. Notably, the carcinogenic risk posed by arsenic (As) through the drinking pathway reached 10−5 a−1, exceeding the maximum levels recommended by certain organizations. These findings provide a critical foundation for managing heavy metals in water-carrying drinking water sources.

Exploring soil pollution patterns in Ghana's northeastern mining zone using machine learning models

This study assessed the pollution status and effectiveness of machine learning models in predicting pollution indices in soils from a mining area in Northeastern Ghana. 552 soil samples were analysed with an Energy Dispersive X-ray Fluorescence (ED-XRF) spectrometer for their elemental concentrations. Four pollution indices; Nemerow Integrated Pollution Index (NIPI), degree of contamination (Cdeg), modified degree of contamination (mCdeg) and Pollution Load Index (PLI). Additionally, the Multivariate Adaptive Regression Splines (MARS) machine learning approach were used. The high CV%, skewness, and kurtosis values show a high degree of variability and uneven distribution patterns which denotes dispersed hotspots that can be interpreted as an influence of gold anomalies and illegal mining activities in the area. V (120.86 mg/L), Cr (242.42 mg/L), Co (30.92 mg/L) Ba (337.62 mg/L), and Zn (35.42 mg/L) recorded values higher than the global and regional contaminant thresholds. The NIPI shows that 46.74% and 26.81% of samples are slightly and moderately polluted respectively. The Cdeg analysis supports these findings, with 36.96% and 41.49% of samples classified as having “moderate” to “considerable” contamination, respectively. The PLI indicates progressive soil quality deterioration (43.84%) of samples reflecting substantial environmental disturbance. The pollution indices show the effect of illegal mining on Shaega, Buin and other areas in the eastern boundary of the study. The MARS models developed for the study demonstrated high predictive capabilities with an R2 value of 0.9665 for model 1 (NIPI), and RMSE and MAE values of 0.8227 and 0.4287 respectively. For model 2 (Cdeg), R2 value of 0.9863, RMSE and MAE of 1.0416 and 0.6181, respectively. Model 3 (mCdeg) produced an R2 value of 0.9844, RMSE and MAE of 0.1225 and 0.0670. These findings suggest MARS models can be an integral tool for soil quality analysis in cooperation with pollution indices. The study suggests that remedial and legislative measures be implemented to address the issue of illegal mining in the area.

Effects of mining activities and municipal wastewaters on element accumulation and integrated biomarker responses of the European chub (Squalius cephalus)

This study aimed to determine concentrations of 29 elements in the gills and liver as well as biomarker response in gills, liver, and blood of European chub from Pek River (exposed to long-term mining activities), and to compare these findings with individuals from Ibar River (influenced by emission of treated municipal wastewater) and Kruščica reservoir (source of drinking water) using inductively-coupled plasma optical emission spectrometry (ICP-OES). The metal pollution index (MPI) was also calculated. Supporting analyses for the detection of the municipal wastewater presence at investigated localities included analyses of microbiological indicators (total coliforms and Escherichia coli) of faecal pollution. We have assessed biomarker responses from molecular to organism level using the condition index, comet assay, micronucleus test, oxidative stress parameters, histopathological alterations, and fluorescence spectroscopy parameters. Multibiomarker analysis was summarized by Integrated Biomarker Response v2 (IBRv2). Among these locations, Kruščica exhibited the lowest, whereas the Pek River displayed the highest values for both categories of indicator bacteria. Due to the porphyry copper ores mining, individuals from Pek River had several times higher Cu concentrations in both gills and liver compared to the other localities which was confirmed by biomarker responses and IBRv2 value. On the contrary, fish from Kruščica reservoir were the least affected by elemental pollution which is also confirmed by low MPI and IBRv2 values. Responses of biomarkers correspond to the elemental accumulation in the liver and gills of the Ibar River are positioned between the Pek River and Kruščica reservoir. Of all the biomarkers analyzed in this study, the condition index was the least sensitive. The results of this study showed that fluorescence spectroscopy may be a method for fast screening of structural changes in gills caused by the pollution burden.

Abstract PR011: Investigating the interplay among allostatic load, social determinants of health, and treatment outcomes in chronic myeloid leukemia patients

Abstract Introduction. The advent of tyrosine kinase inhibitors (TKIs) has transformed chronic myeloid leukemia (CML) into a chronic condition, allowing many patients (pts) to achieve survival rates comparable to the general population. Yet, most pts patients require lifelong therapy, regular follow-up, and management of TKI side effects, posing challenges within the healthcare system alongside structural and financial barriers. We have previously found that CML pts with an allostatic load (AL) burden indicating cumulative stress, experience worse treatment outcomes. In light of this, we investigated whether AL is a biological indicator of social determinants of health (SDH) and its correlation with CML treatment outcomes. Methods. We conducted a single-institution retrospective study, enrolling CML pts and assessing 23 biomarkers across four domains (cardiovascular, metabolic, immunologic, and neuroendocrine) required to calculate the AL score at the time of the first visit. Pts were sorted into low and high AL groups using the cohort's median score of 5 as the threshold. SDH was evaluated at both individual and population levels by integrating data from medical records with the SDH database from the Agency for Healthcare Research and Quality. Statistical analyses, including chi-square and Fisher’s exact tests, were conducted with significance set at p<0.05. Results. Between 2003 and 2023, data from 108 CML pts undergoing first-line treatment were retrieved. Pts with high AL were more likely to be older (mean age 53.8 vs. 47.2 years, p=0.03), and a greater proportion were identified as Black compared to those in the low AL cohort (25.5% vs. 12.3%, p=0.01). We identified an association between high AL and overall mortality (13.7% vs. 1.8%, p=0.02), with effects trending towards a higher risk of CML-specific death (6.4% vs. 0, p=0.05). Higher AL was correlated with adverse SDH, such as reliance on public health insurance (32% vs. 52.2%, p=0.04), living alone (67.7% vs. 86.8%, p=0.05), and lack of regular exercise (38.9% vs. 7.4%, p=0.01). Geographic inequality was identified, as patients with high AL were more likely to reside in Georgia (GA) compared to South Carolina and other states (66.7% vs. 27.5% vs. 5.9%, p=0.01). Indeed, pts in GA who traveled shorter distances to the treatment facility and resided in areas with higher particulate matter levels, as an indicator of air pollution, were less likely to achieve major molecular response (p=0.011 and p=0.008, respectively). SDH such as regular exercise, home environment, and health insurance were associated with overall and CML-specific survival. However, birth country, language, household income, and education, were not associated with either AL or treatment outcomes. Conclusion. Adverse SDH significantly amplifies the burden of AL, serving as a comprehensive indicator of chronic stress, health behaviors, and environmental conditions. Our findings highlight the intricate interplay between social, economic, and environmental factors in shaping treatment outcomes among CML patients. Citation Format: Marisol Miranda-Galvis, Muhannad Sharara, Kellen C. Tjioe, McKenzie Maloney Maloney, Vamsi Kota, Anand Jillella, Locke Bryan, Amany R. Keruakous, Jorge E. Cortes. Investigating the interplay among allostatic load, social determinants of health, and treatment outcomes in chronic myeloid leukemia patients [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr PR011.

Source Apportionment and Risk Assessment of Potentially Toxic Elements Based on PCA and PMF Model in Black Soil Area of Hailun City, Northeast China.

This study assessed the presence of potentially toxic elements (PTEs) in China's northeastern black soil belt, an area with limited prior research. We collected 304 soil samples (0-20 cm) from Gonghe Town, Hailun City, and analyzed the PTE contamination degree using the single-factor pollution index and Nemerow pollution index. The results demonstrated that the mean concentrations of arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), nickel (Ni), lead (Pb), and zinc (Zn) were 11.16, 0.11, 65.29, 22.56, 0.03, 27.07, 26.09, and 66.01 mg/kg, respectively. Source apportionment was conducted via correlation analysis, principal component analysis, and positive matrix factorization, identifying four main sources: natural (33.2%), irrigation (29.5%), fuel (23.4%), and fertilizer (13.2%). The ecological risk index indicated a slight ecological risk, while the human health risk showed that non-carcinogenic risks were negligible and carcinogenic risks were acceptable. Our findings emphasize the need to prioritize controlling PTEs from fertilizer, particularly cadmium, and to a lesser extent, irrigation and fuel sources, focusing on As, Pband Hg. This research provides critical insights for policymakers aiming to manage PTE contamination in black soils.

Comparative Analysis of Water Quality in Major Rivers of Türkiye Using Hydrochemical and Pollution Indices

Comparative Analysis of Water Quality in Major Rivers of Türkiye Using Hydrochemical and Pollution Indices

Benthic Ostracods as Pollution Indicator: A Case Study from Sharm Obhur, Red Sea Coast, Saudi Arabia

Benthic Ostracods as Pollution Indicator: A Case Study from Sharm Obhur, Red Sea Coast, Saudi Arabia

Geochemical baseline establishment and accumulation characteristics of soil heavy metals in Sabaochaqu watershed at the source of Yangtze River, Qinghai-Tibet Plateau

The establishment of soil geochemical baseline and heavy metal pollution assessment in the Qinghai-Tibet Plateau is of great significance for guiding environmental management in the high-cold and high-altitude regions. A total of 126 topsoil samples (0–20 cm) were collected and the contents of Cu, Pb, Zn, Ni, Cr, Cd, As and Hg were determined in the Sabaochaqu basin of the Tuotuo River, the source of the Yangtze River, in the Tibetan Plateau. The baseline values of 8 heavy metals were determined by mathematical statistics, iterative 2times standard deviation method, cumulative frequency and reference element standardization, and the soil heavy metal pollution in the study area was assessed by enrichment factor method and pollution index method. The results showed that the average contents of As, Cd, Cr, Cu, Hg, Ni, Pb and Zn were 31.84, 0.29, 66.07, 17.35, 0.021, 27.86, 49.35 and 88.56 mg/kg, respectively. Baseline values were 22.24, 0.217, 64.16, 15.69, 0.0191, 26.46, 34.91, and 68.62 mg/kg, respectively. There is a great difference between the baseline value of soil heavy metals in study area and the Xizang soil background value, especially the baseline value of Cd was 2.68 times of its background value. The results of the pollution evaluation based on the baseline values showed that the 8 heavy metals were slightly enriched, and the overall pollution status was light pollution, and measures should be taken to control and manage them. The research results can provide a reference value for the evaluation of soil heavy metal pollution in the source region of the Yangtze River, and also provide a theoretical basis for the construction of soil heavy metal baseline values in similar high-cold and high-altitude regions.

Exploring the temporal toxicity signature: A baseline evaluation of the heavy metal concentration in estuarine core sediments in the coastal region of cauvery delta, bay of bengal.

Globally, the concentration of heavy metals and sediment toxicity analysis are significant liabilities to aquatic environments. This scrutiny outlines the sediment textures, heavy metals and toxicity status associated with environmental pollution indices in the core sediment of the Cauvery and Vettar estuaries, East coast of India. The impact of rapid industrialization, urbanization, harbour activities and agricultural activities influences on the twain estuary is a significant concern to designate the environment. The contamination status of the sediments affects the potential biodiversity, ecological risks and human health. A total of two core sediments were recovered from the Cauvery and Vettar estuaries in March 2023 to decipher the environmental pollution status. Meticulous observation of the textural studies underscores the prevalence of sand content in Cauvery, and Vettar sediments consist of predominate clay content and minor silt contents. Furthermore, the organic matter is augmented in the Vettar River due to the higher input of waste disposal, seaweeds and algae due to the surrounding landmass. Twain core sediments argue that heavy metal concentration is decreasing in order as Fe > Zn > Ni > Pb > Cu > Cr by using portable X-ray fluorescence (pXRF) spectrometry. Remarkable results of environmental pollution indices such as Igeo, Ef, Cf, Cd and mCd state very highly polluted, extreme enrichments, high contamination and very high degree of contamination. Furthermore, the potential ecological risk indices such as PLI, SQGs, and PERI argue polluted, medium to high toxicity and moderate adverse ecological risk to the estuarine regions. Statistical analysis of the heavy metal affirms the enrichment of Fe metals may derive from lithogenic and/or anthropogenic influences, and the other studied metals such as Cu, Ni, Zn, Pb and Cr may be influenced by the anthropogenic activities in the aspect of point and non-point pollution sources. This could result from both estuaries undergoing higher pollution, in which the Vettar estuary is a considerable environmental risk zone compared to the Cauvery river due to the impact of industrial effluents and rapid urbanization activities. This finding underscores the urgent need for enhanced estuarine sediment quality study and comprehensive assessment of sediment toxicity, regulating the beneficial acumen for the government to follow the suitable remediation on the embellish policy of river and marine environments.

Salt Tolerance of Fungi and Prospects for Mycodiagnostics of Contamination in Saline Soils

The review is devoted to the analysis of the characteristics of salt-tolerant fungi in order to identify the possibility of their use for indicating chemical contamination of highly mineralized soils and the search for potential test species for laboratory mycotesting. A list of representatives of halophilic and halotolerant genera of micromycetes is given, which can serve as indicators of pollution by heavy metals, oil products and other toxicants against the background of increased mineralization of soil substrates. For biotesting of soils with an average level of mineralization, micromycetes belonging to moderate halotolerant species are proposed as promising. The morphological, physiological and molecular mechanisms of adaptation of halophilic and halotolerant fungi to conditions of increased salinity of habitats are analyzed. The effects on fungal communities, which are caused by a combination of salinity with chemical pollution of different nature, are considered. Methodological aspects of the practical use of salt-tolerant fungi for biodiagnostics of the degree of unfavourability of saline soils are considered: the composition of media, cultivation conditions, and test reactions of fungal cultures that are optimal for an adequate assessment of the degree of halotolerance of fungi and ecotoxicity of soil samples.

Soil type data provide new methods and insights for heavy metal pollution assessment and driving factors analysis

Assessing heavy metal pollution and understanding the driving factors are crucial for monitoring and managing soil pollution. This study developed two modified assessment methods (NIPIt and NECI) based on soil type-specific background values and pollution indices, and combined them with the receptor model to evaluate pollution status. Additionally, a structural equation model was used to analyze the driving factors of soil heavy metal pollution. Results showed that the average NIPIt and NECI were 1.48 and 0.92, respectively, indicating a low pollution risk level. In some areas, Cd and Hg were the primary heavy metals contributing to pollution risk, with their highest average concentrations exceeding soil type-specific background values by 2.06 and 2.04 times, respectively. Additionally, in black soils, meadow soils, and chernozems, heavy metals primarily originated from natural sources, accounting for 48.92 %, 45.98 %, and 45.58 %, respectively. In aeolian soils, agricultural sources were predominant, contributing 43.38 %. Soil pH and organic matter were key soil properties affecting NECI and NIPIt, with direct effects of 0.36 and −0.19, respectively. This study aims to provide new methods and insights for the comprehensive assessment and driving factors analysis of soil heavy metal pollution, with the goal of enhancing pollution monitoring and reducing risk.

Land-Use Pattern-Based Spatial Variation of Physicochemical Parameters and Efficacy of Safe Drinking Water Supply along the Mahaweli River, Sri Lanka

Exploration of the pollution status of river-based water sources is important to ensure quality and safe drinking water supply for the public. The present study investigated physicochemical parameters of surface water in the upper segment of River Mahaweli, which provides drinking water to the Nuwara Eliya and Kandy districts of Sri Lanka. River surface water from 15 intakes and treated water from 14 Water Treatment Plants (WTPs) were tested for pH, water temperature, turbidity, EC, COD, 6 anions, 21 cations, 3 pesticides, and 30 antibiotics once every 3 months from June 2022 to July 2023. Except for turbidity and iron concentrations, all other parameters were within the permissible range as per the Sri Lanka Standard Specification for Potable Water (SLS 614:2013). The uppermost Kotagala WTP raw water had a high concentration of iron due to runoff from areas with abundant iron-bearing minerals. Turbidity increased as the river flowed downstream, reaching its highest value of 13.43 NTU at the lowermost Haragama. Four intakes had raw surface water suitable for drinking as per the Water Quality Index (WQI). Pollution increased gradually towards downstream mainly due to agricultural runoff, industrial effluents, and urbanization. Poor water quality at the upstream Thalawakale-Nanuoya intake was due to highly contaminated effluent water coming from Lake Gregory in Nuwara Eliya. Cluster analysis categorized WTP locations in the river segment into 3 clusters as low, moderate, and high based on contaminations. Principal component analysis revealed that the significance of the 41.56% variance of the raw water was due to the pH and the presence of heavy metals V, Cr, Ni, Rb, Co, Sr, and As. All treated water from 15 WTPs had very good to excellent quality. In general, heavy metal contamination was low as indicated by the heavy metal pollution index (HPI) and heavy metal evaluation index (HEI). The treatment process could remove up to 94.7% of the turbidity. This is the first attempt to cluster the river catchment of the Mahaweli River based on physicochemical parameters of river water. We present here the land-use pattern-based pollution of the river and efficacy of the water treatment process using the Mahaweli River Basin as a case study. Regular monitoring and treatment adjustments at identified points are recommended to maintain the delivery of safe drinking water.

Multidimensional Approach for the Assessment of Environmental Pollution and Health Risk Associated With V, Ni, Cr, Cu, and Zn in the Recent Sediments of Kabini Interstate River, Southeastern Western Ghats, India

ABSTRACTThe present work intends to study the variation of heavy metals (HMs) to scrutinize the scenario of pollution index and associated environmental risk, as well as source weathering conditions along the Kabini River. The decreasing order of concentration of HMs along the basin is Cr > V > Ni > Zn > Cu. The paper spotlights the pollution grade in sediments, assessed by the geo‐accumulation index (Igeo), contamination factor (Cf), pollution load index (PLI), and enrichment factor (Ef). The assessment of ecological risk is studied as potential ecological risk index (RI), toxic risk index (TRI), and modified hazard quotients (mHQs). As per the Igeo and Cf, V and Cr concentrations are higher in the region. Further, PLI confirmed that 35% of samples exceeded the limits of sediment quality guidelines. The RI and TRI values show that a higher ecological risk is associated with Ni, V, and Cr and with Cu and Cr, respectively. Additionally, the 23% Ni and 20% Cu samples from mHQ indicate the severity of pollution in the aquatic environment. The inputs from anthropogenic and natural sources change the concentration of these HMs along the region. Moreover, the study of CIA and plagioclase index of alteration plots confirmed the low to intense weathering conditions. The statistical approach shows the linkage between Cr–V, Cu–Zn, and principal component analysis–derived prominent sources: industrial and agricultural runoff, as well as higher silicate weathering, contribute to the HMs concentration in the region. The Kabini River passes through different climatic and land‐use domains of Kerala and Karnataka, which eventually regulate the HM concentration and geo‐environmental processes in the region and affect the health risk to humans in one or the other way. The reference data generated from the present work are absolutely new and would be significant in the future for deriving sustainable development plans for the well‐being of human beings and precious natural resources.

Spatiotemporal distribution of cyanobacteria in relation to water chemistry of Sutlej River, Punjab (India).

In this investigation, the spatiotemporal distribution of cyanobacteria and their relationships with variations in water chemistry (physico-chemical parameters and heavy metal) of Sutlej River, Punjab (India) has been analyzed by employing multivariate statistical methods. Sutlej River exhibits a rich array of cyanobacterial diversity, comprising 28 species across 15 genera, distributed among 11 families and spanning 5 orders within the class Cyanophyceae. In terms of relative abundance, Microcystis aeruginosa (17.47%) was documented as the most abundant taxa followed by Microcystis robusta (16.55%), Merismopedia punctata (11.03%), Arthrospira fusiformis (6.67%) and Pseudanabaena galeata (3.68%). Significant variations were observed among sampling sites in most of the physico-chemical parameters. Principal Component Analysis delineated sampling sites into two discernible groups according to variations in water chemistry. River Pollution Index (RPI) showed that river water is under the unpolluted (RPI 1.5) to negligibly polluted category in the upstream sites, while moderately polluted (RPI 5.5) in the downstream sites. Heavy metal Pollution Index (HPI) revealed consistent heavy metal contamination at sites RWS7 and RWS8 across all seasons. Conversely, site RWS1 consistently exhibited lower HPI values throughout the three studied seasons. Further, Canonical Correspondence Analysis identified that pH, TDS, TA, NO3, Na, and NH4 are the key physicochemical parameters which affect the spatiotemporal distribution of cyanobacteria in the studied river system. Overall, this study will offer significant information for hydrologists, ecologists, and taxonomists to develop future holistic strategies for further monitoring of the Sutlej River and other similar habitats.

In Situ Photoelectrodeposited Polyaniline on Ti‐Doping Hematite For Highly Selective Photoelectrochemical Oxygen Demand Determination

AbstractChemical Oxygen Demand (COD), as a detection indicator of water pollution, is of particular importance in assessing organic pollution in water. Furthermore, accurate and simple measuring COD methods are essential for water quality assessment and pollution control. However, the photoelectrochemical oxygen demand (PECOD) measurement, as one of the measuring COD methods, is affected by the reaction of water splitting, which is one of the hindrances to the commercialization of the analytical method of the PeCOD measurement. Hence, to overcome this challenge, a new PANI/Ti:Fe2O3 photoanode is constructed by hydrothermal and photoelectrochemical (PEC) deposition methods and investigated their optical properties and photoactivity. Under optimization conditions, it is discovered that the oxidation of organic compounds produces a net steady‐state current (inet) is directly proportional to COD concentration, with a detection limit of 1 mM glucose solution and a wide linear detection range of 1–78.125 mM, which is suitable for high concentration of glucose detection. As has been noted, PANI/Ti:Fe2O3 photoanode overcomes the obstacles to the practical application and eventual commercialization of the PECOD technology.

Eco-Environmental Assessment and Trend Analysis of the Yangtze River Middle Reaches Megalopolis Based on a Modified Remote Sensing Ecological Index

China’s accelerating pace of urbanization has placed severe pressure on its ecosystems. Hence, the monitoring and assessment of eco-environmental quality has significant implications for sustainable urban development. By introducing a pollution index, a modified remote sensing ecological index (MRSEI) was constructed to more comprehensively evaluate the spatiotemporal distribution of the eco-environment quality in the middle reaches of the Yangtze River where urbanization has been developing rapidly. Future trends in eco-environmental quality were analyzed using Theil–Sen trend analysis, the Mann–Kendall test, and the Hurst exponent. Environmental influencing factors were also analyzed. Our results show that: (1) The impact of pollution factors on urban agglomerations cannot be overlooked. The MRSEI model introduces a pollution indicator to better assess the eco-environmental quality of urban agglomeration areas. (2) The eco-environmental quality is high in the south and east and low in the north and west, with overall levels ranging between moderate and good. (3) The eco-environmental quality remained stable, improved, and degraded in 86.3%, 3.1%, and 10.7% of the study area, respectively. (4) The land use and land cover type are directly related to the eco-environment. Climate factors indirectly affect the eco-environment. Human activities in cities and urban peripheries lead to land use changes and industrial pollution, which significantly affect environmental quality.

Analysis of the environmental state of the Sarata River in Odesa Region

The relevance of the study is dictated by the need to preserve the water resources of southern Ukraine and ensure their good environmental condition. In the context of military operations, Odesa Region plays a key role in providing the country with agricultural products because of significant damage incurred to agricultural lands of Mykolaiv and Kherson Regions in the course of military actions. Hence the role of irrigation and the need to restore and modernize irrigation systems are growing. One of fresh water reservoirs of Odesa Region is Sasyk reservoir (artificially created as part of the estuary) which accumulates fresh water supplied from the Danube. The Kogylnyk and the Sarata rivers flow into the northern part of the reservoir and can worsen its hydroecological condition. The subject of the study: pollution of the rivers across North-Western Black Sea Coast by chemicals. The object of the study: the environmental state of the Sarata River. The study is aimed at assessing the environmental state and environmental risks of chemical pollution of the Sarata River. The water quality assessment was performed based on a modified version of water pollution index (WPI). Biogenic substances (ammonium nitrogen, nitrite nitrogen, nitrate nitrogen) were identified as the main pollutants. The content of chlorides and sulfates is also significant. The assessment of the pollution risks by biogenic substances is based on calculations of the statistical probit function. The source materials of the research include hydrochemical observations made by the State Agency of Water Resources of Ukraine for the period from 2007 to 2023 in the upper reaches of the Sarata River - village of Miniailivka (94 km from the mouth, near the border with Moldova) and in the lower reaches of the Sarata River - village of Bilolissya (14.3 km from the mouth). The analysis of probability of exceeding the MPC for fishery use indicated that, in terms of nitrite ions and nitrate ions, such probability is higher in the upper basin than in the lower one. According to other indicators, the probability of exceeding the MPC by pollutants is either almost the same or slightly increased in the lower reaches. The assessment of water quality according to the modified WPI (dissolved oxygen, BOD5, ammonium, nitrite and nitrate ions, phosphates) showed that the water quality in the Sarata River mainly belongs to the "moderately polluted" and "polluted" classes. According to the environmental risk indicators, it was established that the possibility of a "high" risk of contamination by biogenic substances does prevail. Its probability is 52.9% for the upper reaches and 60% for the lower reaches. The "high" level of class IV pollution (ER=0.60-0.79) corresponds to an "unsatisfactory" environmental condition. The probability of achieving the class of a "good" environmental condition (class II, ER=0.20-0.39) is quite small: 17.6% in the upper reaches and only 6.67% in the lower reaches. Thus, the Sarata River belongs to such rivers, the natural properties of which underwent significant changes as a result of sewage delivery from "Sarata Komunservis" utility enterprise, settlement of Sarata. Contaminated waters are unsuitable for drinking, household and sports purposes, as well as for fish farming. The quality of the Sarata River's water has a negative impact on the environmental state of Sasyk reservoir.