Heavy Metal Pollution Index Research Articles

Impact of Ship Breaking Activities on the Water Quality at the Coastal Area of Chattogram, Bangladesh

The ship breaking area of Chattogram is one of the most ecologically effective regions in Bangladesh. It includes wealthy biodiversity that consists of numerous species which are endemic to this region. The impact of various physico-chemical parameters on pollution is a significant concern for both the environment and biodiversity. In order to evaluate the potential ecological impact, water samples were obtained using standard procedures from several sites within ship breaking yards. The values of physico-chemical parameters like, temperature, EC, TDS, TSS, pH, DO, BOD, salinity, oil and greases were found 29.65 ºC, 2028.87 μS/cm, 1014.89 mg/L, 7392.42 mg/L,8.03, 7.28 mg/L, 4.03 mg/L, 12.83 ppt, 7166.64 mg/L, respectively. A decreasing trend in the amount of trace elements present in water and sediment: Pb (0.46 mg/L) > Cr (0.49 mg/L) > As (0.205 mg/L) > Cd (0.049 mg/L). The concentrations of toxic metals, however, exceeded the permissible thresholds in both regions. Lead and chromium had no seasonal effects, whereas arsenic and cadmium significantly varied with the seasons. The evaluation of the heavy metal pollution index (HPI) and contamination factor (CF) showed that the study area had a critical score of water quality (HPI > 100). The metal concentrations had an elevated contamination effect (CI > 3). According to the study’s findings, the ship breaking site is moderately polluted with heavy metals and posed a risk to the ecosystem.

Environmental Pollution Assessment of Heavy Metals in Soils and Crops in Xinping Area of Yunnan Province, China

With the development of the economy and society, the environmental problems caused by heavy metals have always been the focus of attention. Strong concern has been recently shown for the heavy metal pollution of soils in southwestern China. The heavy metals of surface soils in the Xinping area of Yunnan province, China are surveyed along with some crop samples. There are 3312 surface soils and 95 crop samples collected in about 370 square kilometers. Heavy metals including As, Cd, Cr, Hg, and Pb and pH are analyzed. New single and integrated pollution indices of heavy metals for soils (PI and PIn) and crops (PIc and PInc) based on Chinese criteria (GB15618-2018 and GB2762-2022) are described and presented here and used to assess the pollution status of heavy metals. The results indicate that the background level of surface soils is about 62.1%, the screening level is about 33.4%, and the intervention level is about 4.5%, which is mainly a result from Cr and spatially coincides with the peridotite rock, indicating a geogenic pollution source. Most crop samples are not contaminated with heavy metals. Comparing the results of the two integrated pollution indices between soils and crops, two inconsistent assessments are observed. One is that some contaminated crops are growing in unpolluted areas (or Type I) and the other is that some uncontaminated crops are growing in polluted areas (or Type II). This indicates a new challenge between the assessment criteria on soils and crops.

Nutrient and heavy metal dynamics in the coastal waters of St. Martin’s island in the Bay of Bengal

Seasonal variation observations were conducted in the coastal waters of St. Martin's Island in the Bay of Bengal to examine the influence of physical processes and the distribution pattern of nutrients in the ocean water. Pollution evaluation indices, health index and statistical techniques were incorporated to assess the heavy metal contamination. Two seasons, cool dry winter and pre-monsoon hot, were considered for sampling from 12 stations around the island. The Cool dry winter season has higher nutrient concentrations than the Pre-monsoon Hot season. The concentration of nutrients appeared as follows: Silicate > Nitrate > Ammonia > Phosphate > Nitrite. PCA and Pearson's Correlation showed that fresh water from nearby rivers, deep water upwelling, and, in some situations, modest anthropogenic sources are crucial. Hence, low DO and phosphate levels during the pre-monsoon hot season indicate there is a planktonic process like photosynthesis prevailing. The island's north-western and south-eastern regions have higher nutrient concentrations, which may be seasonal and due to wind action. Pb, Cu, As, Cr, Cd, and Zn were also considered to comprehend the island's geo-chemical perspectives and ecological and human health risks. The Pre-monsoon Heavy Metal Pollution Index (HPI) and Heavy Metal Evaluation Index (HEI) demonstrated that some places are much higher than the threshold limit, even though no significantly higher value was detected in the cool winter season. The Nemerow Index, the Total Ecological Risk Index (TERI), indicated that heavy metal contamination was severe to moderate and low to moderate. Finally, Pearson's correlation showed the association between physical and chemical characteristics, similar to PCA and Pearson's correlation for nutrients and heavy metals. Thus, this research may help shed light on the state of the seas around St. Martin's Island. This study may also provide explicit insights for the authority to take the necessary measures to preserve marine ecology and the associated terrestrial ecosystem.

Heavy metal contamination and risk assessment on ecological and public health in a tropical estuarine river

Heavy metals contamination of water is one of the most severe environmental and public health issues. The present study was conducted to assess the levels of lead (Pb), chromium (Cr), cadmium (Cd), arsenic (As), copper (Cu) and zinc (Zn) in surface water of the Pasur River estuary in Bangladesh along with their health risk through the ingestion and dermal exposure. The decreasing order of studied metals was Cr > Pb >Cu > Zn > As > Cd with the mean value of 0.050 > 0.024 > 0.021 > 0.014 > 0.012 > 0.006 mg/L respectively. Pb, Cr, Cd and Zn concentration in water samples exceeded the safe limits of drinking water and thereby not safe for drinking. The multivariate analysis identified the common anthropogenic source and existence of studied metals. Heavy metal pollution index (HPI) and heavy metal evaluation index (HEI) indicated significant contamination of water. The HQ and HI through ingestion and dermal contact were <1 except for the adult, whereas HQ (only for As) and HI value through ingestion was >1 indicating an unacceptable risk of non-carcinogenic effects on public health. Carcinogenic risk through ingestion (CRing) indicated that consumption of water from Pasur River estuary may develop cancer risk of Cd. Therefore, strict rules and regulations must be adopted to reduce water contamination of this tidal river from anthropogenic sources for improving the health of this riverine ecosystem.

Comprehensive health risk analysis of heavy metal pollution using water quality indices and Monte Carlo simulation in R software

Rapid urbanization, population growth, agricultural practices, and industrial activities have led to widespread groundwater contamination. This study evaluated heavy metal contamination in residential drinking water in Shiraz, Iran (2021). The analysis involved 80 groundwater samples collected across wet and dry seasons. Water quality was comprehensively assessed using several indices, including the heavy metals evaluation index (HEI), heavy metal pollution index (HPI), contamination degree (CD), and metal index (MI). Carcinogenic and non-carcinogenic risk assessments were conducted using deterministic and probabilistic approaches for exposed populations. In the non-carcinogenic risk assessment, the chronic daily intake (CDI), hazard quotient (HQ), and hazard index (HI) are employed. The precision of risk assessment was bolstered through the utilization of Monte Carlo simulation, executed using the R software platform. Based on the results, in both wet and dry seasons, Zinc (Zn) consistently demonstrates the highest mean concentration, followed by Manganese (Mn) and Chromium (Cr). During the wet and dry seasons, 25% and 40% of the regions exhibited high CD, respectively. According to non-carcinogenic risk assessment, Cr presents the highest CDI and HQ in children and adults, followed by Mn, As and HI values, indicating elevated risk for children. The highest carcinogenic risk was for Cr in adults, while the lowest was for Cd in children. The sensitivity analysis found that heavy metal concentration and ingestion rate significantly impact both carcinogenic and non-carcinogenic risks. These findings provide critical insights for shaping policy and allocating resources towards effectively managing heavy metal contamination in residential drinking water.

Impacts of climate change and coastal salinization on the environmental risk of heavy metal contamination along the odisha coast, India.

Climate change-mediated rise in sea level and storm surges, along with indiscriminate exploitation of groundwater along populous coastal regions have led to seawater intrusion. Studies on groundwater salinization and heavy metal contamination trends are limited. Present study investigated the heavy metal contamination, associated risks and provided initial information on the impacts of groundwater salinization on heavy metals along the coastal plains of Odisha, India. Total 50 groundwater samples (25 each in post- and pre-monsoon) were collected and analysed. Concentrations of Fe (44%), Mn (44%), As (4%) and Al (4%) in post-monsoon and Fe (32%), Mn (32%), As (4%), B (8%) and Ni (16%) in pre-monsoon exceeded Bureau of Indian Standards (BIS) drinking water limits. High concentrations of heavy metals (Fe, Sr, Mn, B, Ba, Li, Ni and Co) and high EC (>3000 μS/cm) indicated that the groundwater-seawater mixing process has enhanced the leaching and ion exchange of metallic ions in central part of the study area. Multivariate statistical analysis suggested leaching process, seawater intrusion and agricultural practices as the main heavy metal sources in the groundwater. 4% of samples in post- and 16% in pre-monsoon represented high heavy metal pollution index (HPI). Pollution indices indicated the central and south-central regions are highly polluted due to saline water intrusion and high agricultural activities. Ecological risks in the groundwater systems found low (ERI <110) in both seasons. Children population found more susceptible to health risks than adults. Hazard index (HI > 1) has shown significant non-carcinogenic risks where Fe, Mn, As, B, Li and Co are the potential contributors. Incremental lifetime cancer risk (ILCR >1.0E-03) has suggested high carcinogenic risks, where As and Ni are the major contributors. The study concluded that groundwater salinization could increase the heavy metal content and associated risks. This would help policymakers to take appropriate measures for sustainable coastal groundwater management.

Distribution characteristics, source identification and health risk assessment of trace metals in the coastal groundwater of Taizhou City, China

This study was carried out to evaluate and analyze the fluctuations in groundwater for certain trace metals (Fe, Mn, Cu, Zn, Al, Cd, Cr, Pb, As, and Se) in Taizhou City over three years (2020–2022), evaluate the potential human health risks due to the consumption of groundwater. To quantify the spatiotemporal changes in groundwater trace metals, the heavy metal pollution index (HPI) and heavy metal evaluation index (HEI) were utilized. Furthermore, multivariate statistical methods were utilized to distinguish the sources of trace elements. Deterministic health risk assessment and Monte Carlo health risk simulation methods were employed to evaluate human health risks associated with exposure to trace metals. The results indicate that areas with higher pollution are in the south-central region, with low HPI increasing from 50% to 75% and low HEI from 68.75% to 81.25%, reflecting improved water quality. Correlation matrix analysis and principal component analysis (PCA) pinpointed anthropogenic sources as major trace metal contributors. Cr and As concentrations were associated with farming activities, Cd and Pb concentrations showed links to local industries such as e-waste recycling and shipbuilding. Furthermore, Cu levels in groundwater was influenced by the combined effects of industry, agriculture, and urban sewage discharge. Based on the hazard quotient (HQ) and hazard index (HI) calculations, the majority of groundwater samples did not exceed the reference values, indicating acceptable noncarcinogenic risks for both adults and children. However, the analysis of carcinogenic risk (CR) and uncertainty revealed an overall decreasing trend in carcinogenic risk, with Cr and Cd possessing the highest potential for causing carcinogenic risks. The sensitivities were 46.3%, 53.3%, and 70.3% for Cr, and 18.8%, 27.6%, and 9.3% for Cd.

Environmental Risk Assessment and Sources of Potentially Toxic Elements in Seawater of Jazan Coastal Area, Saudi Arabia

High levels of potentially toxic elements (PTEs) in water bodies negatively affect the biota of aquatic ecosystems and surrounding environments. A risk assessment investigation of the levels and distribution of PTEs in the seawater of the Jazan coastal area, southwest Saudi Arabia, was conducted. Thirty-two surface seawater samples were collected, and contamination (Cd) and heavy metal pollution (HPI) indices, as well as multivariate statistics, were applied. The average PTE levels (µg/L), in descending order of magnitude, were Cu (2.56), Pb (2.27), Ni (1.30), Cr (1.28), Zn (1.04), Sb (0.36), Co (0.22), and Cd (0.06). A fluctuating pattern without a fixed direction was detected in the spatial distribution of these metals, with increased pollution being linked to high metal levels as shown by some samples. The HPI indicated low pollution in 50% of the samples and medium pollution in the remaining 50%, whereas the Cd indicated low contamination with PTEs. The absence of significant correlations between pairs of metals indicated different sources of metal pollution. Lithogenic sources are implicated in the supply of Co, Ni, Pb, and Sb, whereas Cr was mainly derived from an anthropogenic source, and combined lithogenic and anthropogenic sources are believed to have contributed Cu and Zn to the area. It is proposed that urbanization, agriculture, and industry are among the potential anthropogenic sources of pollutants on the Jazan coastline. Soils generated on the undifferentiated Quaternary rocks along the investigated area are the main lithogenic sources.

Assessment of Groundwater Quality by Heavy Metal Pollution Index in Ijare Rural Community and Alagbaka Urban Area in Ondo State, Nigeria

Assessment of Groundwater Quality by Heavy Metal Pollution Index in Ijare Rural Community and Alagbaka Urban Area in Ondo State, Nigeria

Heavy metals in five commonly consumed fish species from River Swat, Pakistan, and their implications for human health using multiple risk assessment approaches

This study analyzed the levels of heavy metals bioaccumulation in commonly consumed riverine fish species, including G. cavia, T. macrolepis, G. gotyla, S. plagiostomus, and M. armatus from River Swat in Pakistan, and quantify their potential risk to children and adults in general and fisherfolk communities using multiple pollution and risk assessment approaches. The highest metal detected by inductive coupled plasma mass spectrometry (ICP-MS) was Zn, which ranged from 49.61 to 116.83 mg/kg, followed by Fe (19.25–101.33 mg/kg) > Mn (5.25–40.35 mg/kg) > Cr (3.05–14.59 mg/kg) > Ni (4.26–11.80 mg/kg) > Al (1.59–12.25 mg/kg) > Cu (1.24–8.59 mg/kg) > Pb (0.29–1.95 mg/kg) > Co (0.08–0.46 mg/kg) > Cd (0.01–0.29 mg/kg), demonstrating consistent fluctuation with the safe recommendations of global regulatory bodies. The average bioaccumulation factor (BAF) values in the examined fish species were high (BAF > 5000) for Pb, Zn, Mn, Cu, Cr, Ni, and Cd, bioaccumulate (1000 > BAF < 5000) for Co, and probable accumulative (BAF <1000) for Fe, and Al, while the overall ∑heavy metals pollution index (MPI) values were greater than one (MPI > 1) indicating sever heavy metals toxicity in G. cavia, followed by S. plagiostomus, M. armatus, G. gotyla, and T. macrolepis. The multivariate Pearson's correlation analysis identified the correlation coefficients between heavy metal pairs (NiCr, CuCr, PbCr, AlCo, CuNi, and PbNi), the hierarchical cluster analysis (CA) determined the origin by categorizing heavy metal accumulation into Cluster-A, Cluster-B, and Cluster-C, and the principal component analysis (PCA) discerned nearby weathering, mining, industrial, municipal, and agricultural activities as the potential sources of heavy metals bioaccumulation in riverine fish. As per human risk perspective, S.plagiostomus contributed significantly to the estimated daily intake (EDI) of heavy metals, followed by G.cavia > M.armatus > G.gotyla > T.macrolepis in dependent children and adults of the fisherfolk followed by the general population. The non-carcinogenic target hazard quotient (THQ) and hazard index (HI) values for heavy metal intake through fish exposure were < 1, while the carcinogenic risk (CR) for individual metal intake and the total carcinogenic risk (TCR) for cumulative Cr, Cd, and Pb intake were within the risk threshold of 10−6–10−4, suggesting an acceptable to high non-carcinogenic and carcinogenic risk for both children and adults in the fisherfolk, followed by the general population.

Multivariate Statistical Methods and GIS-Based Evaluation of Potable Water in Urban Children’s Parks Due to Potentially Toxic Elements Contamination: A Children’s Health Risk Assessment Study in a Developing Country

Contamination of potentially toxic elements (PTEs) has received widespread attention in urban children’s parks (UCPs) worldwide in the past few decades. However, the risk assessment of PTEs in drinking water sources of UCPs is still unknown particularly in developing countries. Hence, the present study investigated the spatial distribution, sources for PTEs (Cd, Cr, Pb, Ni, and Cu), and health risk assessment in drinking water sources of UCPs in Khyber Pakhtunkhwa, Pakistan. Among PTEs, Cd, Cr, and Pb had low to high concentrations and exceeded the safe limits of WHO and PAK-EPA in most UCPs. PCA results showed high anthropogenic and low natural sources, contributing to the release of PTEs in all UCPs. Heavy-metal pollution index (PTE-PI) results showed low to high pollution levels for all UCPs, with the highest values of 113 and 116 for Sardaryab Park Charsadda (SPC) and Zoo Park Peshawar (ZPP), respectively. Heavy-metal evaluation index (PTE-EI) results also showed low to high pollution levels for all UCPs. UCPs samples (50%) showed low pollution levels in PTE-PI results. To the contrary, UCPs samples (50%) exhibited high pollution levels in PTE-EI results. The non-carcinogenic risk of HQ and HI values of all PTEs were below the permissible limit (&lt;1) for adults and children via ingestion and dermal contact. CR and TCR results showed that PTEs (Cr, Cd, Pb, and Ni) had the highest carcinogenic risk (&gt;1.00 × 10−4) for both adults and children in all UCPs, except Cd and Ni for adults via the ingestion route, while Cr values (&gt;1.00 × 10−4) were exceeded for children in some of the UCPs via the dermal route. Consequently, long-term exposure to toxic PTEs could pose a carcinogenic risk to the local population. Thus, the present study suggests that the government should implement enforcement with firm protocols and monitoring guidelines of environmental regulations to mitigate PTEs originating from anthropogenic sources in order to reduce health risks and improve public health safety in urban areas.

Heavy Metal Distribution Characteristics, Water Quality Evaluation, and Health Risk Evaluation of Surface Water in Abandoned Multi-Year Pyrite Mine Area

Acid mine drainage (AMD) is a major anthropogenic source of heavy metal discharge worldwide. However, little research has been carried out on the development of AMD in abandoned pyrite mines and the heavy metal contamination of mine surface water. The aim of this study was to investigate and assess heavy metal pollution in three streams within an abandoned pyrite mine area in southeastern Shaanxi Province, China. Surface water pollution was assessed using the pollution index assessment method and the health risk assessment model. The results showed that the combined heavy metal pollution indices of the surveyed rivers were Tielu Creek (4699.227), Jiancao Creek (228.840), and Daoban Creek (68.106). After multivariate statistical analysis, it was found that the tailings slag and mine chamber in the abandoned mine area were the main causes of AMD, and AMD posed a serious risk of heavy metal pollution to the surrounding waters. The risk of carcinogenicity of heavy metals is also quite high in the surface water of mining area. Therefore, there is an urgent need to ecologically manage heavy metal pollution from abandoned mine sites, and this study provides insights into understanding heavy metal pollution in the aquatic environment of abandoned mine sites.

Trace Metal Contamination and Associated Health Effects in the Shivnath River Tributaries

Present study focus on manganese (Mn), iron (Fe), copper (Cu), chromium (Cr), and aluminium (Al), trace metals contamination assessment in some tributaries of Shivnath River. To assess the cumulative impact of the studied trace metals on Shivnath River water quality, the heavy metal pollution index (HPI) is calculated. Since the Shivnath River is one of the major rivers of the studied area the impact of the studied trace metals present in river water on human health is evaluated by computing human exposure (EXPing), hazardous quotient (HQing), human exposure surface water (HEsw), carcinogenic risk (CRing). The study reveals no severe health effects due to presence of studied trace metals in rivers since the obtained values were less than 1.0, but in future care should be taken to avoid any unfavourable conditions.

An integrated approach for understanding natural -and anthropogenic controls on water quality in arid and semi-arid environments

The objective of this review is to highlight the need for an integrated approach to the understanding of the major processes controlling the hydrochemical composition of water bodies in drylands using multivariate statistics, water quality index and heavy metal pollution index. The integrated approach to the hydrochemical investigation of streams and aquifers in drylands is essential owing to their distinctive climate, notably, low rainfall and high temperature. Studies on water quality in arid and semi-arid areas using multivariate analysis and water quality indices were scrutinized. Results showed that the hydrochemistry of streams and aquifers is controlled by both the natural geogenic processes and anthropogenic activities. However, in-depth understanding of geochemistry and land use types, as well as climatic vagaries, is required, to be able to discriminate these processes, since several ions of rock minerals origin are increasingly being added into the environment through human activities. While the sources of solutes and processes controlling the hydrochemistry of streams and aquifers can be established through application of multivariate analysis, this technique is limited in water quality investigations since it cannot measure the suitability of water for domestic, agriculture and industrial uses. Thus, an integrated approach incorporating water quality indices in conjunction with multivariate analysis is required. This is essential owing to the fact that the suitability of water for various uses is central to any hydrogeochemical investigation in arid and semi-arid environments. Thus, it is expected that future hydrochemical studies would apply this approach.

Pollution of the Niger Delta with total petroleum hydrocarbons, heavy metals and nutrients in relation to seasonal dynamics

The African Niger Delta is among the world’s most important wetlands in which the ecological effects of intensive oil exploitation and global change are not well documented. We characterized the seasonal dynamics and pollution with total-petroleum-hydrocarbons (TPHs), heavy-metals (HMs) and nutrient-loads in relation to climate-driven variables. High TPH concentrations up to 889 mg/L and HMs up to 13.119 mg/L were found in water samples, with pronounced spatio-temporal variation throughout the year. HM pollution index and contamination factor indicate serious ecological and human health hazards, especially for Cd, Cu, Hg, and Ni. Significant differences in TPHs/HMs were observed between sites and seasons, with correlations between TPHs-HMs, and climate-variables and TPHs-HMs. Nutrient levels, turbidity, salinity, temperature, and SO42- were high and interlinked with the variability of TPHs/HMs being greatest during wet season. These findings suggest an urgent need for improved pollution control in the Niger Delta taking into account the observed spatio-temporal variation and the exacerbation of effects in light of climate change. Given the high levels of contamination, further assessments of exposure effects and bioaccumulation in biota should include future climate change scenarios and effects on humans who intensively depend on the system for drinking water, food supply and livelihood.

Ameliorative effect of natural floating island as fish aggregating devices on heavy metals distribution in a freshwater wetland

Growing human population and climate change are leading reasons for water quality deterioration globally; and ecologically important waterbodies including freshwater wetlands are in a vulnerable state due to increasing concentrations of pollutants like heavy metals. Given the declining health of these valuable resources, the present study was conducted to evaluate the effect of natural floating island in the form of fish aggregating devices (FADs) made of native weed mass on the distribution of heavy metals in the abiotic and bio compartments of a freshwater wetland. Lower concentrations of surface water heavy metals were observed inside the FADs with a reduction of 73.91%, 65.22% and 40.57–49.16% for Cd, Pb and other metals (viz. Co, Cr, Cu, Ni and Zn), respectively as compared to outside FAD. These led to 14.72–55.39% reduction in the heavy metal pollution indices inside the FAD surface water. The fish species inside the FADs were also found less contaminated (24.07–25.07% reduction) with lower health risk indices. The study signifies the valuable contribution of natural floating island as FADs in ameliorating the effect of heavy metals pollution emphasizing the tremendous role of the natural floating islands in sustainable maintenance of freshwater wetlands for better human health and livelihood.

Water quality and health risk assessment of heavy metals in groundwater of Ranbir Singh Pura tehsil of Jammu and Kashmir, India.

Groundwater is one of the important sources available for drinking, agricultural, domestic, and various other purposes in the study area. Study area is having agricultural importance and is famous for Basmati rice production in the world. In order to assess water suitability for irrigation and drinking purposes, 25 sampling sites were selected and water samples were collected from handpumps, borewells and motors from May 2022 to June 2022. Fifteen physico-chemical parameters and water quality index (WQI) was calculated to assess the drinking water suitability. The results obtained then compared with the BIS (2012) and WHO drinking water guidelines. For irrigation water suitability, irrigation water quality index (IWQI) and other indices were calculated. Heavy metal health risk assessment was also evaluated using target hazard quotient (THQ), carcinogenic risks (CR), non-carcinogenic risks, heavy metal pollution index (HPI), etc. Study found 60% of water samples under poor category of WQI. All water samples were found suitable for irrigation purposes according to different indices except for permeability index for which only 32% samples were found suitable. IWQI classifies 52%, 32%, and 12% of water samples under moderate, low, and no restriction category respectively. Groundwater of the study area found to be contaminated with copper (Cu), iron (Fe), lead (Pb), and chromium (Cr) while low contamination of zinc (Zn) and arsenic (As) was found according to heavy metal evaluation index (HEI). High contamination of chromium (HPI= 9740.8) and lead (HPI=188) was recorded as per HPI. HQ value for men, women, and children in case of zinc were found safe while HQ values for copper and lead in all population groups were found at risk. Overall, the study area was found highly contaminated with the lead, copper, and chromium concentrations. Thus, study recommends regular monitoring of the groundwater of study area as well as treatment before using this water for drinking purposes.

Detrimental influence of industrial effluents, especially heavy metals, on limnological parameters of water and nutritional profile in addition to enzymatic activities of fish, Sperata seenghala (Sykes, 1839) from diverse Ramsar sites, India (Punjab).

The present research was designed to determine the nutritive value of the liver and intestine of fish, Sperata seenghala, the impact of effluence load on limnological parameters of water and proximate composition of fish organs, especially on fatty acids, liver enzymatic activities, seasonal variations in the nutritional profile of fish, and to check and compare the pollution status of Ramsar sites in Punjab by calculating the water quality index, heavy metal pollution index, and metal index from June 2018 to August 2020. WQI of Harike wetland was found to be 53.95, which depicts that water quality in this region is "poor". At Nangal wetland, water quality index was reported to be "excellent" quality water and fit for the whole ecological unit. Overall heavy metal pollution index for Harike wetland was reported 174.569, whereas for Nangal wetland it was 5.994, depicting massive contaminant loads in a polluted region. MI value was also recorded as being higher (6.9336) in polluted habitat than in control habitat (0.8175). In fish liver, significant (p < 0.05) higher mean total lipids (6.73%), total proteins (3.98%), moisture (77.69%), ash (3.56%), and carbohydrates (3.79%) were observed in the samples from Nangal wetland than Harike wetland. A similar trend was reported in all biochemical contents of the fish intestine. Enzyme activities such as aspartate-aminotransferase and alanine-aminotransferase were significantly elevated (p < 0.05) in the specimens collected from the polluted region. The mean total n-3 (except in spring), n-6 polyunsaturated fatty acids (except in winter), and average monounsaturated and saturated fatty acids diminished significantly (p < 0.05) in the liver of fish from contaminated habitat than control site. In the intestine of fish collected from the polluted region, significant reductions in the mean total n-3 (except in autumn as well as summer), total n-6 PUFAs (in autumn and winter), and total SFAs were reported than control site.

Evaluation of Heavy Metal Pollution in Rice (Oryza sativa L.) Fields of Bafra Plain

Heavy metals are naturally present in the soils in trace quantity. Besides, some soils include these elements at high levels resulting from the weathering of minerals or human activities. Contamination of these metals has been of great concern in the environment interrelatedly with their toxicity, persistence and non-degradability. So, this article aimed to evaluate heavy metal pollution by using several pollution indices contamination factor (CF), degree of contamination (CD), pollution load index (PLI), summarization of the sources of heavy metals, and change of these metals along soil depth. For this purpose, 10 coordinated soil samples were taken from 0-20 cm and 20-40 cm depths in the rice fields of Bafra Plain in Samsun-Türkiye. In these samples, some physico-chemical soil characteristics (texture, pH, electrical conductivity, organic matter and lime content, available phosphorus and cation exchange capacity) and heavy metal contents Zinc (Zn), copper (Cu), nickel (Ni), cobalt (Co), cadmium (Cd), chromium (Cr) and lead (Pb) were determined. According to the results, metal contents were determined between 39.79-58.44 mg kg-1, 32.15-68.31 mg kg-1, 75.68-132.6 mg kg-1, 11.95-18.02 mg kg-1, 0.001-0.278 mg kg-1, 61.88-102.5 mg kg-1, and 9.942-14.67 mg kg-1 for Zn, Cu, Ni, Co, Cd, Cr and Pb, respectively. While Cd content was higher at 0-20 cm depth, Cr, Ni and Zn values were higher at 20-40 cm. Cu, Pb and Co values did not show significant change with depth. Average CF values for heavy metals were determined as Ni&gt;Pb&gt;Cr&gt;Cu&gt;Cd&gt;Zn&gt;Co. Degree of contamination values varied between 4.922-7.848 and PLI values varied between 0.946-1.028. In all elements, CF and CD values were classified in the group of low and moderate contamination. Besides, significant relationships were found between soil physicochemical properties, heavy metal concentrations and pollution indices.

Occurrence, speciation, and controls on arsenic mobilization in the alluvial aquifer system of the Ghaghara basin, India.

High concentrations of arsenic (As) in groundwater are among the long-standing environmental problems on the planet. Due to adverse impacts on the human and aquatic system, characterization and quantification of individual inorganic As species are crucial in understanding the occurrence, environmental fate, behaviour, and toxicity in natural waters. This study presents As concentration and its speciation As(III) and As(V) data, including the interrelationship with other major and trace aqueous solutes from parts of the Ghaghara basin, India. More than half (57%) of the groundwater samples exhibited elevated As concentrations (> 10μg/L), whereas 67.4% of samples have higher As(III) values relative to As(V), signifying a potential risk of As(III) toxicity. The elevated concentration of As was associated with higher Fe, Mn, and HCO3-, especially in samples from shallow well depth. PHREEQC modeling demonstrates the presence of mineral phases such as hematite, goethite, rhodochrosite, etc. Therefore, it is inferred that the release of As from sediment particles into pore water via microbially mediated Fe/Mn oxyhydroxides, and As(V) reduction processes mainly control high As concentrations. The heavy metal pollution indices (HPI) and (HEI) values revealed heavy metal pollution in low-lying areas deposited by relatively younger sediments along the Ghaghara River. Large-scale agricultural practices, overexploitation of groundwater, and indiscriminate sewage disposal, in addition to geogenic factors, cannot be ruled out as potential contributors to As mobilization in the region. This study recommends conducting seasonal hydrogeochemical monitoring and investigating regional natural background levels of As, to precisely understand the controlling mechanistic pathways of As release.