Levels Of Heavy Metal Contamination Research Articles

Current state, sources, and potential risk of heavy metals in sediments of typical inner lakes in the Dongting Lake Area

The region has been increasingly experiencing environmental issues related to heavy metals (HMs) due to human activities. However, the contamination levels of HMs (Cr, Ni, Cu, Zn, As, Cd, and Pb) in various inner lakes in the Dongting Lake area remain unclear. In this study, surface sediment samples from 9 inner lakes and sediment core samples from 3 typical inner lakes were collected to evaluate the spatial distribution, contamination status, environmental and ecological risks, and possible sources of these HMs. The results showed that all HMs, except Zn, exceeded background values, with particularly high levels observed in aquaculture lakes compared to other lakes. Vertical profiles of HMs from 3 lakes show that the various types of lakes in the study area have different pollution histories. Additionally, results from Sediment quality guidelines (SQGs), Contamination factor (CF), Geo-accumulation index method (Igeo), and Hakanson potential ecological risk index (PERI) indicated that As, Cd, and Pb are the primary pollutants. The multivariate analysis concluded that Ni, Cu, Zn, As, Cd, and Pb had anthropogenic sources, primarily from agricultural, fisheries, industrial, and transportation activities, while Cr was influenced by natural factors. The results of this study enhance our understanding of sedimentary metal content in inner lakes and emphasize the importance of controlling HMs content in these lakes. This information is crucial for developing effective lake management and pollution control strategies.

Advanced approach combines integrated weight water quality index and potential toxic elements for environmental and health risk assessment supported by simulation technique in Oued Souf, Algeria

The current research study evaluated the health and environmental risks issues associated with potentially toxic elements (PTEs) in the complex terminal aquifer located in the Algerian desert. The methods used included principal component and cluster (dendrogram) analysis to estimate source of ions and contamination. Various indices such as the Heavy Metal Pollution Index (HPI), Metal Index, hazard quotient, hazard index (HI), and cancer risk (CR) were applied to assess both environmental and human health risks. Furthermore, the Monte Carlo method was applied for probabilistic assessment of carcinogenic and non-carcinogenic risks through oral and dermal exposure routes in both adults and children. The results revealed that approximately 16% of the samples fell within the low pollution category (HPI < 100), indicating relatively lower levels of heavy metal contamination. However, the remaining 84% of the samples exhibited high pollution levels, indicating a significant presence of heavy metal pollutants in the northeastern part of the investigated area. The calculated average risk index (RI) for the collected samples was 18.99, with a range from 0.03 to 103.21. This indicates that a large portion, 82% of the samples, could cause low ecological risk (RI < 30), whereas the remaining 18% indicate a significant environmental pollution risk. The HI for oral ingestion showed that adults had HI values ranging from 0.231 to 1.54, while children exhibited higher values, ranging from 0.884 to 5.9 (Fig. 5a). For dermal exposure, HI values in adults ranged from 2.71E−07 to 8.74E−06 and in children, from 2.18E−06 to 7.03E−05. These findings highlight the potential non-carcinogenic risks associated with oral exposure to PTEs and underscore the increased vulnerability of children to metals such as Fe, Mn, Pb, and Cr. Most samples showed CR exceeding 1 × 10−4 for chromium (Cr) and lead (Pb), indicating a significant vulnerability to carcinogenic effects in both children and adults.

Potential Combination of Phytoremediation Plants and Compost in Remediation of Hg in Ex-Gold Mine Soil Contaminated Mercury (Hg)

Heavy metal mercury pollution in the environment can have negative impacts on both surrounding ecosystems and human health. Sources of mercury pollution often come from mining activities, particularly from many unlicensed gold mines (PETI) that use the mercury amalgamation method to extract gold. Due to the persistent, bioaccumulative, and toxic nature of mercury, contamination in the soil has increased. One effort to reduce mercury toxicity is the application of absorption methods using phytoremediation plants and compost as regulating factors. The aim of this study is to review sources of information related to the use of phytoremediation plants and the application of compost as remediators to clean mercury (Hg)-contaminated soil. To reduce levels of heavy metal contamination, plants employ five phytoremediation mechanisms: phytoextraction, phytostabilization, rhizofiltration, phyto degradation, and phytovolatilization. Therefore, selecting hyperaccumulator plants that have the ability to accumulate mercury (Hg) at levels 100 times higher than ordinary plants is crucial for effective remediation. Additionally, the use of compost as a source of organic material can enhance mercury mobility. The addition of organic materials such as compost can increase C organic content, cation exchange capacity (CEC), pH, and Hg-chelate formation, thereby maximizing mercury absorption by plants. This combination has a positive impact on reducing mercury levels in the soil and is environmentally safe.

A comprehensive study of source apportionment, spatial distribution, and health risks assessment of heavy metal(loid)s in the surface soils of a semi-arid mining region in Matehuala, Mexico

BackgroundThis study investigates the contamination level, spatial distribution, pollution sources, potential ecological risks, and human health risks associated with heavy metal(loid)s (i.e., arsenic (As), copper (Cu), iron (Fe), manganese (Mn), lead (Pb), and zinc (Zn)) in surface soils within the mining region of Matehuala, located in central Mexico. ObjectivesThe primary objectives are to estimate the contamination level of heavy metal(loid)s, identify pollution sources, assess potential ecological risks, and evaluate human health risks associated with heavy metal(loid) contamination. MethodsSoil samples from the study area were analysed using various indices including Igeo, Cf, PLI, mCd, EF, and PERI to evaluate contamination levels. Source apportionment of heavy metal(loid)s was conducted using the APCS-MLR and PMF receptor models. Spatial distribution patterns were determined using the most efficient interpolation technique among five different approaches. The total carcinogenic risk index (TCR) and total non-carcinogenic index (THI) were used in this study to assess the potential carcinogenic and non-carcinogenic hazards posed by heavy metal(loid)s in surface soil to human health. ResultsThe study reveals a high contamination level of heavy metal(loid)s in the surface soil, posing considerable ecological risks. As was identified as a priority metal for regulatory control measures. Mining and smelting activities were identified as the primary factors influencing heavy metal(loid) distributions. Based on spatial distribution mapping, concentrations were higher in the northern, western, and central regions of the study area. As and Fe were found to pose considerable and moderate ecological risks, respectively. Health risk evaluation indicated significant levels of carcinogenic risks for both adults and children, with higher risks for children. ConclusionThis study highlights the urgent need for monitoring heavy metal(loid) contamination in Matehuala's soils, particularly in regions experiencing strong economic growth, to mitigate potential human health and ecological risks associated with heavy metal(loid) pollution.

THE POTENTIAL OF Catharanthus Roseus AS A PHYTOREMEDIATION AGENT FOR HEAVY METAL REMOVAL IN CONTAMINATED SOIL

Heavy metals from human activities, such as industrial emissions and mining waste, contribute to environmental, nutritional, and health issues. Catharanthus roseus, a phytoremediation plant, was tested to determine the levels of heavy metals in soil and plants. The experiment involved preparing various amounts of heavy metals by combining four elements: Cadmium (Cd), Copper (Cu), Lead (Pb), and Zinc (Zn). Four treatment groups were tested, each with varying levels of heavy metal contamination. The initial group (T0) served as the positive control, while the next four groups (T1-T4) were subjected to escalating levels of heavy metals. T1 was given a 200ml solution containing 0.9 (Cd) + 4.0 (Cu) + 0.18 (Pb) + 6.9 (Zn). T2 was given a 200ml solution containing 11.90 (Cd) +19.80 (Cu) +36.00 (Pb) + 54.3 (Zn). T3 was given a 200ml solution containing 23.80 (Cd) + 39.60 (Cu) + 72.00 (Pb) + 108.6 (Zn). T4 was given a 200ml solution containing of 23.80 (Cd) + 39.60 (Cu) + 72.00 (Pb) + 108.6 (Zn). The dataset included measurements of soil pH, heavy metal concentrations, plant height, and shoot and root length. The results showed that the T3 solution, consisting of 23.80 (Cd) + 39.60 (Cu) + 72.00 (Pb) + 108.6 (Zn), had the most favourable plant growth performance based on soil and plant concentrations. This suggests that immediate action is needed to ensure safe food availability.

Assessment of Heavy Metal Contamination and Potential Health Risk of Selected Fish Species in Dhaka District

Fish is a rich source of quality protein and fatty acids. Bangladesh's average daily fish consumption is 67.8 grams per people. Fish species are also prone to heavy metal contamination from their surrounding environment. The main objective of this research was to assess the degree of risk associated with the consumption of various fish species in Dhaka, Bangladesh. Three fish species—Tilapia (Oreochromis mossambicus), Shorputi (Systomus sarana), and Mola (Amblypharyngodon mola)—from three local markets in Savar Union, Dhaka, Bangladesh, were selected for analysis. The Kjeldahl technique, Folch method, and several formulae were used to determine the protein, fat, ash, and moisture content for the proximate analysis. The concentration of heavy metals was determined using Atomic Absorption Spectrophotometry (AAS). The estimated daily intake (EDI), target hazard quotient (THQ), total target hazard quotient (TTHQ), hazard index (HI), and cancer risk (CR) were used to evaluate the danger to human health. Tilapia had the highest moisture and lipid content, whereas Shorputi and Mola had the highest protein and ash contents, ranging from 20.77% to 18.16%, respectively. The mean concentration of heavy metals in fish was determined to be Pb&gt;Ni&gt;Cr&gt;Cd in this study. Every fish species had extremely high levels of lead (Pb), with the Shorputi fish having the highest levels. Fish from the Shorputi species had the highest EDI value. Pb&gt;Ni&gt;Cr&gt;Cd was the trace element EDI for adults. Among all species, only Pd had a THQ value higher than 1. The CR value across all species were within E-3 and E-6 range, while the HI value was &gt;1. In conclusion, the highest average Pb concentrations were detected in Shorputi, while the highest amounts of Cd, Cr, and Ni were observed in Tilapia. The findings of this study recommended that the Bangladeshi government regularly assess the levels of dangerous heavy metal and metalloid contamination in the daily meals of its citizens in order to enforce regulatory limits and determine the likelihood of long-term exposure. Bioresearch Commu. 10(2): 1524-1531, 2024 (July)

Groundwater Quality Assessment with Respect to Heavy Metal Content by using Heavy Metal Pollution Index (HPI) of Moradabad District, Uttar Pradesh, India

Heavy metal pollution index (HPI), is a rating method to assess the water quality and to categorize the groundwater pollution with respect to heavy metals content. The aims of the present study are to look over the current status of heavy metals pollution in and around Moradabad city. Heavy metal pollution in water has gained universal consciousness due to its tenacity, accumulation in the food chain and negative effects on ecological as well as human health. Its variation in concentration can cause deterioration of water. The study focuses on examining the content of heavy metal (Zn, Fe, Cd, Mn, Pb, Ni, Cu, and Cr) in the 30 water samples from the surrounding areas of Moradabad city. The concentrations of Cd, Mn, Fe, Cu, Pb, Zn, Ni, and Cr in water samples were recorded in the pre- and post-monsoon season of 2017. The examined samples reveal that the contamination level of heavy metal is in the following sequence Ni&gt;Fe&gt;Pb&gt;Cd&gt;Cr&gt;Cu&gt;Zn&gt;Mn in premonsoon 2017, whereas in postmonsoon season, heavy metals values are shown as Fe&gt;Pb&gt;Ni&gt;Mn&gt;Cr&gt; Cu&gt;Zn&gt;Cd. The HPI average value in pre-monsoon 2017 is 13.07, which recommended that the groundwater quality is good. While in post-monsoon season HPI average values has been 159.26 suggesting that the water quality is poor to inferior. The correlation matrix has been evaluated and shows a positive correlation with the elements. The immense production of industrial solid waste in Moradabad city and its improper disposal in the form of heap piled outside the city area generates leachate. Heavy metal leaching from these disposal points may contaminate the groundwater as well as surface water resources. The study shows that heavy metal concentration has a noticeable rise in water due to different anthropogenic and various natural sources of contamination.

Composition of heavy metals in sediment, water, and fish of the Ganga and Yamuna Rivers in two major cities of India.

The rapid industrial development in the Indian capital region has led to significant waste generation, which, despite undergoing treatment prior to disposal, contributes substantially to water body contamination. Given the diverse nature of these wastes and their potential repercussions across the food chain, a study was conducted to evaluate heavy metal contamination levels in the Ganga and Yamuna Rivers of two major cities. Six heavy metals (Pb, Cd, Hg, Cu, Cr, and Zn) were analyzed in fish, water, and sediment samples by utilizing flame atomic absorption spectrophotometry (Avanta Σ) from March 2019 to February 2020. Results revealed distinct heavy metal distribution patterns, with Cr > Zn > Pb > Cu > Cd > Hg in the Ganga River and Zn > Cr > Pb > Cu > Cd > Hg in the Yamuna River for fish samples. Additionally, levels of Hg in Cyprinus carpio and Sperata oar from the Ganga River, and Pb, Cd, Hg, and Cr in Salmophasia bacaila and Mystus cavasius from the Yamuna River exceeded WHO/FAO permissible limits. In water samples, the predominant heavy metal sequences were Pb > Cu > Zn > Cr > Cd > Hg for the Ganga River and Cr > Zn > Pb > Cu > Cd > Hg for the Yamuna River, with Pb, Cr, Zn, and Cd surpassing WHO standards. Sediment analysis revealed varying heavy metal compositions, with Zn > Cr > Pb > Cu > Cd > Hg in the Ganga River and Cr > Zn > Pb > Cu > Cd > Hg in the Yamuna River. While drinking water and fish from the Ganga River were deemed safe for consumption, those from the Yamuna River were not. Given the toxic nature of heavy metals and their detrimental health impacts, regular monitoring and effective management strategies are imperative.

Evidence of heavy metal in soil, irrigation water and vegetable cultivated in peri‑urban area of Yaoundé-Cameroon

Environmental pollution from anthropogenic activities is of global concern. The levels of heavy metal contamination were evaluated in the soil and irrigation water, and their transferability to the cultivated plant was appraised in the locality of Nkolbisson, Yaoundé-Cameroun. The levels of Zn, Cu, Cd, Ni, Pb, Cr, and Mn contamination were evaluated to determine the current status, possible source(s), bio-accumulation in food crops, the suitability of the water for irrigation purposes, and hence the probable health risk. The analysis of soils, waters, and crops (Corchorus olitorius and Lactuca sativa) samples has shown high levels of heavy metal contamination. Cd, Ni, and Cr concentrations in water samples (0.98, 2.230, and 2.635 mg/l) were above the threshold set by FAO for irrigation water. In agricultural soils, only the level of Mn (1013.090 mg/kg) contained in soil samples was above the European Union (EU) and the Canadian Council of Ministers for Environment (CCME) thresholds of toxicity. Except for Pb (0.361; 0.394 and 0.043; 0.041 mg/kg DM) and Mn (113.457; 123.341 and 173.667; 180.321 mg/kg DM), the concentration of heavy metals analysed in plant samples were above the standard values in the edible parts. Market gardening in this city presents risks due to the presence of heavy metals in soils and irrigation waters. Thus, market gardeners must be taking appropriate measures to avoid crop contamination. The bioconcentration and translocation factors have shown that Lactuca sativa can be used for phytoextraction of Zn, Cu and Cd whereas Corchorus olitorius can be used for phytomobilization of the same elements.

Land-Use–Land Cover Changes in the Urban River’s Buffer Zone and Variability of Discharge, Water, and Sediment Quality—A Case of Urban Catchment of the Ngerengere River in Tanzania

The physical integrity of the Ngerengere River and its three tributaries drains within Morogoro Municipality were evaluated by assessing the variations in land-use–land cover (LULC) in the river’s buffer zone, the discharge, and the contamination of river water and sediment from nutrients and heavy metals. Integrated geospatial techniques were used to classify the LULC in the river’s buffer zone. In contrast, the velocity area method and monitoring data from the Wami-Ruvu Basin were used for the discharge measurements. Furthermore, atomic absorption spectrophotometry was used during the laboratory analysis to determine the level of nutrients and heavy metals in the water and river sediment across the 13 sampling locations. The LULC assessment in the river’s buffer during the sampling year of 2023 showed that bare land and built-up areas dominate the river’s buffer, with a coverage of 28% and 38% of the area distribution. The higher discharge across the sampling stations was in the upstream reaches at 3.73 m3/s and 2.36 m3/s at the confluences. The highest concentrations of heavy metals in the water for the dry and wet seasons were 0.09 ± 0.01, 0.25 ± 0.01, 0.03 ± 0.02, 0.73 ± 0.04, 4.07 ± 0.08, and 3.07 ± 0.04 mg/L, respectively, for Pb, Cr, Cd, Cu, Zn, and Ni. The order of magnitude of the heavy metal concentration in the sediments was Zn &gt; Ni &gt; Cr &gt; Cu &gt; Cd &gt; Pb, while the highest NO2−, NO3−, NH3, and PO43− in the water and sediment were 2.05 ± 0.01, 0.394 ± 0.527 0.66 ± 0.05, and 0.63 ± 0.01 mg/L, and 2.64 ± 0.03, 0.63 ± 0.01, 2.36 ± 0.01, and 48.16 ± 0.01 mg/kg, respectively, across all sampling seasons. This study highlights the significant impact of urbanization on river integrity, revealing elevated levels of heavy metal contamination in both water and sediment, the variability of discharge, and alterations in the LULC in the rivers’ buffer. This study recommends the continuous monitoring of the river water quality and quantity of the urban rivers, and the overall land-use plans for conserving river ecosystems.

Bioaccumulation and translocation of radionuclides heavy metals in Cynodon dactylon: A phytoremediation approach in Al-Dora refinery

Oil extraction methods such as fracking and drilling can disperse radioactive elements into the environment, posing potential hazards. Certain plants like Bermuda grass can combat this through rhizodegradation, a process that breaks down pollutants into harmless substances. The efficiency of this process varies by location and is influenced by factors such as soil compatibility and the presence of beneficial microbes. A study showed that Bermuda grass roots absorbed high levels of radioactive elements, especially Uranium in the soil. The distribution and concentration of these isotopes in Bermuda grass varied across different sites. For instance, Cesium-137 showed higher activity in leaves than in soil. These findings highlight the varied accumulation patterns of elements in Bermuda grass and the influence of natural radionuclide distribution on the environment. Approaches like soil amendments, microbial assistance, and genetically modified Bermuda grass can enhance rhizoremediation efficiency. Strategic planning and species selection are key to overcoming rhizoremediation challenges and enhancing its effectiveness. In addition, soil samples from the AL-Dora Refinery showed a high degree of contamination by heavy metals, with the emission from burning fuel and crude oil being the main sources. This indicates the high contamination of soil by these heavy metals. Overall, the text discusses the potential of Bermuda grass in mitigating the environmental impacts of oil extraction through rhizoremediation, and the challenges and strategies in enhancing its effectiveness. It also highlights the issue of soil contamination by heavy metals due to oil refinery emissions. This research examines the levels of heavy metal contamination in the soil of the Al-Dora refinery area, situated in central Iraq. The contamination factor (Cf) was employed to ascertain the contamination status, revealing a significant to extremely high degree of contamination by various heavy metals. The study further investigates the bioaccumulation and translocation of these heavy metals from the soil to the roots and leaves of Cynodon dactylon plants. Two methodologies were utilized to assess the role of Cynodon dactylon in soil phytoremediation: a comparison of heavy metal concentrations in plant parts with global standards, and the application of the Bioconcentration factor (BCF). The findings suggest a high potential for Cynodon dactylon to be employed in the clean-up and phytoremediation process of the contaminated soil. This presents a promising strategy towards environmental remediation in areas contaminated with heavy metals.

Bacterial-fungal interactions and response to heavy metal contamination of soil in agricultural areas.

Long-term heavy metal contamination of soil affects the structure and function of microbial communities. The aim of our study was to investigate the effect of soil heavy metal contamination on microorganisms and the impact of different heavy metal pollution levels on the microbial interactions. We collected soil samples and determined soil properties. Microbial diversity was analyzed in two groups of samples using high-throughput sequencing technology. Additionally, we constructed microbial networks to analyze microbial interactions. The pollution load index (PLI) < 1 indicates that the area is not polluted. 1 < PLI < 2 represents moderate pollution. PLI was 1.05 and 0.14 for the heavy metal contaminated area and the uncontaminated area, respectively. Cd, Hg, Pb, Zn, and Cu were identified as the major contaminants in the contaminated area, with the contamination factors were 30.35, 11.26, 5.46, 5.19, and 2.46, respectively. The diversities and compositions of the bacterial community varied significantly between the two groups. Compared to the uncontaminated area, the co-occurrence network between bacterial and fungal species in the contaminated area was more complex. The keystone taxa of the co-occurrence network in the contaminated area were more than those in the uncontaminated area and were completely different from it. Heavy metal concentrations played a crucial role in shaping the difference in microbial community compositions. Microorganisms adapt to long-term and moderate levels of heavy metal contamination through enhanced interactions. Bacteria resistant to heavy metal concentrations may play an important role in soils contaminated with moderate levels of heavy metals over long periods of time.

Assessment of Water Quality, Ecological and Health Risks of Inland Water Bodies in Mexico: A Case Study of Lake Chapala

Water security threatens the world's population, so the assessment of the quality of water in reservoirs is one of the priority issues and represents a challenge for the sustainability of ecosystems and the human population. The aim is to evaluate the physicochemical parameters and heavy metals of the water of Lake Chapala to evaluate its water quality, during the period 2010-2023, and to estimate the ecological and health risks. The results will provide valuable information on water quality management and protection of human health. The design is an ecological study, using water quality, pollution risk, ecological and health risk indices. The place and duration of the study is the Lake Chapala during the period 2010-2023. The methodology consisted of obtaining the quality data of the Water Lake Chapala through the State Water Commission, the National Water Commission and studies conducted by the University of Guadalajara. The analyses were conducted on a monthly basis from 2010 to 2023. Subsequently, the CWQI, WQI, NP, HPI, HEI, DC, PERI, HQ, HI, THI, CR and TCR indices were calculated to determine water quality and ecological and health risks. The results showed que the distribution of parameter concentration showed great spatial variation, but not temporal; the TDS, Turbidity, pH, Al, As, Cr, Cu, Mn, Pb and Zn with percentages above the CCME standard, but most of them within the NOM-001-SEMARNAT-2021. The heavy metals Al, As, Cr, Pb and Zn have concentration percentages of more than 100% with respect to the international standard. The remaining 14 parameters are within both national and international standards. Pearson's correlation analysis showed that none of the trace elements have positive correlations with each other. Water quality according to the WQI of 178 was categorized as poor quality, while for the CWQI almost all uses except grazing, water quality is poor (20-35). According to the NP index (3.8 to 670), the concentrations of heavy metals showed high levels of contamination. The HPI index (88.6) showed moderate to high levels of heavy metal contamination. The HEI index showed &lt;10 levels, indicating low contamination. The DC had a value of 0.2-18.2, classified as a high degree of contamination. The PERI index showed that the ecological risk from heavy metals is high. Non-carcinogenic risk indices indicate that lake water is not suitable for drinking, and poses a high health risk via ingestion, while dermal contact does not pose a health risk to residential and recreational recipients. The carcinogenic risk index is negligible to acceptable. The conclusion is according to the water quality, ecological and health risk indices, the water quality of Lake Chapala is poor, with a high degree of contamination and represents ecological and health risks (non-carcinogenic). It is recommended that the use of lake water does not include its ingestion to avoid health problems, and it is important to take measures to sanitize the lake to avoid ecological and health risks.

Evaluation of river water quality using multivariate statistics and water quality indices: A case of Göynük canyon (Turkey)

Natural and anthropogenic water pollution caused by heavy metals has become a major problem worldwide. As a result of these processes, many harmful heavy metals are mixed into the water and endanger the environment and human health. Therefore, this study aimed to investigate the hydrogeochemical properties of the stream waters of Göynük Canyon (Göynük Stream), which is located in southern Turkey, an important touristic region of Antalya. A total of 44 water samples were retained to evaluate the geochemical type, heavy metal contamination level, and suitability for drinking and irrigation of Göynük Canyon Stream waters. All samples were analysed by inductively coupled plasma mass spectrometry (ICP-MS), X-ray fluorescence (XRF), and multi-parameter portable water quality assessment.Analysed water samples were found to be of classes II and III in terms of overall water quality. The average hardness level is above the limit values. The results of geochemical analyses showed that the common water types in the region are Mg–Ca–HCO3, Ca–Mg–HCO3, Ca–Mg–HCO3–SO4, and Ca–Mg–HCO3–Cl-water facies. Most of the samples belong to the "rock weathering dominated" region represented in the Gibbs diagram. The hydrogen ion concentration (pH), electrical conductivity (EC), and total dissolved solids (TDS) values vary between respectively 6.5–7.9; 230.4–720.8 μS/cm, and 149–468 mg/L. Cations and anions followed the order Ca2+ > Mg2+ > Na+ > K+ and HCO3− > SO42− > Cl− > F− > NO3−. Heavy metal anomalies in water followed an increasing order: Cu < As < Pb < Ni < Ba < Fe < Cr < Mn < Zn < Sr. These heavy metals showed high index values (Poseidon index (PoS), contamination factor (CF), enrichment factor (EF), geochemical index (Igeo), heavy metals pollution index (HPI), contamination degree (Cd), in some water samples. There is a spatial anomaly in these locations related to limestone and ophiolite. This water can be used for irrigation purposes according to Wilcox, the United States salinity laboratory diagram (USSL), permeability index (PI), Kelly's ratio (KR), and Residual Sodium Carbonate (RSC).

Evaluation and Source Apportionment on Potentially Toxic Elements Pollution of Agricultural Soil in Mango Planting Areas in Panzhihua City, China

ABSTRACT Heavy metal pollution in agricultural soil has a wide range of sources and an enormous scope of influence, bringing about severe environmental risk. In this study, we used Pearson correlation analysis, combined with principal component and cluster analysis (PCA/CA) to comprehensively analyze the sources of soil heavy metal contamination in a mango plantation area in Panzhihua City. We performed a spatial distribution of heavy metal contamination levels via ArcGIS for single factor and Nemerow Contamination Index. The results showed that PTEs exceeded background values of soil pollution in Sichuan Province. The enrichment of Cr, Ni and Zn were caused by the development of local industry. Cu is mainly from atmospheric dust. Various pollution sources controlled the accumulation of Cd, whereas that of As and Pb were related to agricultural activities and transportation. The spatial distribution of the pollution indices indicated that the soil in the study area was mild to severe pollution with compound PTEs. Chemical speciation analysis showed that the ecological risk of PTEs enrichment in the study area was slight. This study highlights the geographic distribution of heavy metal contamination levels and source resolution, providing targeting for local regulatory authorities to improve soil environmental quality.

From soil to health hazards: Heavy metals contamination in northern India and health risk assessment

Heavy metals contamination in soil is a global concern affecting the environment with far-reaching consequences for ecosystems and the health of human beings. Heavy metals contamination of soil entails a significant threat to the environment and human health. This research paper focuses on the quantification of heavy metals contamination in soil in Kanpur district, a highly industrialized and densely populated region in India. The study was aimed to identify the sources of heavy metals, map their spatial distribution, and evaluate the potential implications on the environment and human well-being. The prime intent of the current study was quantification of heavy metals in the soil as well as the comparison of risk on the health of human being using two different methods i.e., US EPA methodology for risk assessment and epidemiological study-based risk assessment. Heavy metals like Fe, Ni, Co, Cu, Mn, Cr, and Cd were analyzed in agricultural samples of soil with the help of inductively coupled plasma optical emission spectroscopy. On the basis of epidemiological data, the attributable and relative risk came out to be 0.001 and 1.060, respectively. On the basis of the calculation of Cr alone, the values of carcinogenic risk for adults came out to be 3.87 × 10−7 and for children it was 3.01 × 10− 6. In conclusion, this research paper highlights the alarming levels of heavy metals contamination in the soil of Kanpur district, emphasizing the urgent need for remediation and mitigation efforts, thereby guiding policy makers and stakeholders in developing targeted strategies for soil protection and safeguarding human health.

Impact of lead and zinc heavy metal pollution on the growth and phytoremediation potential of Sulla carnosa in Sebkha el Kalbia, Tunisia.

Heavy metal pollution from human and natural activities poses significant environmental and health concerns for wildlife and humans, with lead and zinc being particularly threatening. This study focuses on Sebkha el Kalbia in Tunisia, highlighting the challenges faced by local communities in addressing heavy metal pollution. The area is prone to contamination through rivers and streams that transport pollutants from industrial zones and rural areas into the salt pan. The recent establishment of an industrial zone has worsened pollution levels, calling for strict regulatory measures and clean technologies to limit heavy metal pollution and protect human health and the environment. The study assesses the impact of lead and zinc pollution on the growth of Sulla carnosa and its potential for phytoremediation. Soil and plant samples from contaminated areas were analyzed, revealing high levels of heavy metal contamination. The growth parameters of Sulla carnosa, such as plant height, weight, and enzymatic activity, were examined, showing a significant reduction in plant growth when exposed to high metal concentrations. Specifically, in the presence of 100ppm of lead (Pb), net photosynthetic assimilation (An) decreased by 52%, while the amount of Pb increased by 78%. At 800ppm of Pb, An decreased by 87%, and the amount of Pb increased by over 800%. Furthermore, the relationship between net photosynthetic assimilation and lead (Pb) content remained significant but negative. At high doses (800ppm), the biomass produced decreases by 64%, while the amount of Zn increases 2.7 times. These results suggest that at low doses, zinc is not toxic. These findings highlight Sulla carnosa as a potential candidate for phytoremediation with preferential metal accumulation in the roots and improved enzymatic activity, underscoring the urgency of addressing heavy metal pollution in Sebkha el Kalbia.

Heavy metal pollution in the nearshore surface sediments north of the Shandong Peninsula and the Western Miao Islands, China

Surface sediment samples (N = 94) were obtained from the west Miao Islands, northern Shandong Peninsula, China, and analyzed for grain size and elements. Based on the classification by Folk and Ward, surface sediments were dominated by silt-sized components, sandy silt, and silt. The mean abundance of heavy metals could be ordered according to Cr > Zn > Ni > Cu> Pb > As> Cd > Hg. According to sediment quality guidelines, surface sediments have a 21 % probability of being toxic. The potential ecological risk index indicates low potential ecological risk, while the enrichment factor and geo-accumulation indices indicate slight to moderate pollution across most of the study area. Pollution load indexes indicate that 38 % of sites are moderately metal contaminated and 62 % of sites are not polluted. The study area was classified according to the level of heavy metal contamination and its sources.

Heavy metal content of selected readily available commercial medicinal plants in Jos Plateau and their potential human health risk

This study determined the level of heavy metal contamination in selected medicinal plants sold in Jos Metropolis and assesses the health risks associated with their consumption. Five commonly used medicinal plants (Annona senegalensis, Mangifera indica, Psidium guajava, Vernonia amygdalina, and Vitex donniana) were analyzed for the presence of arsenic (As), cadmium (Cd), copper (Cu), mercury (Hg), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn) respectively using inductively coupled plasma mass spectrometry (ICP-MS). The result showed that the concentrations of As, Cd, Hg, Mn, and Zn in all the plants and Pb levels in two plants, V. amygdalina and V. donniana were significantly higher than the WHO recommended limits, indicating a potential health hazard. The calculated values of the hazard quotient (HQ), hazard index (HI), and cancer risk (CR) for the heavy metals exceed the acceptable levels for both adults and children, suggesting a high vulnerability to heavy metal toxicity and carcinogenicity with the highest and lowest HI values obtained by V. amygdalina (47.3) for children and P. guajava (9.63) for adults. The CR associated with Ni and As for adults and children indicated high carcinogenic risk. In contrast, the CR values for Cd and Pb for adults and children indicated a moderate CR. Based on the results and risk assessment provided by this study, the consumption of medicinal plants suggests a high vulnerability to heavy metal toxicity. It can be concluded that the consumption of medicinal plants poses a serious threat to human health due to heavy metal contamination and calls for implementing preventive measures and risk communication among users of these products to safeguard the health of the residents.

Soil heavy metal pollution and ecological risk assessment in disturbed and undisturbed soil of Morigaon, Assam

Soil heavy metal pollution and ecological risk assessment in disturbed and undisturbed soil of Morigaon, Assam