Heavy Metal Contamination In Groundwater Research Articles

Assessment of heavy metal contamination in the groundwater of Gujarat, India using the heavy metal pollution index

Groundwater serves as a vital water source for a significant population in the Gujarat region of India. However, substantial contamination from heavy metals, pose a serious threat to human health through various pathways, including drinking water. The rapid industrial and agricultural growth in recent years has exacerbated heavy metal pollution in the state. This study focuses on assessing the heavy metal contamination in Gujarat's groundwater using the Heavy Metal Pollution Index (HPI). The research covers the entire state, considering its diverse physical, climatic, topographical, and geographical conditions. The HPI scores obtained from individual studies highlight the extent of pollution caused by heavy metals. The overall findings underscore the severe problem of heavy metal contamination in Gujarat's groundwater and the associated health risks. Various other pollution indicators, including the Heavy Metal Evaluation Index, Degree of Contamination, Metal Index, and Water Pollution Index are discussed as tools to assess contamination levels. These indices compare concentrations of different heavy metals with established limits to determine the pollution level. The goal is to provide valuable insights for investors and policymakers in formulating strategies to manage and reduce heavy metal contamination across the state. Additionally, the review explores effective, environmentally friendly, and economically viable treatment techniques to remove heavy metals from aquatic systems, safeguarding the environment. By employing pollution indicators and remedial actions, this study aims to guide efforts in mitigating the impact of heavy metal contamination in Gujarat's groundwater.

Evaluating hydrogeochemistry and heavy metal contamination of groundwater at Ranipet environs: employing multivariate statistics, agricultural indices, and health risk assessment.

Water plays an essential role in sustaining life on Earth as an indispensable natural resource. In recent decades, dependence on groundwater for domestic and industrial purposes has become inevitable. The Ranipet industrial environs (RIE) has many tanneries and chemical industries, which affects the groundwater quality. This study assessed groundwater quality and its suitability for domestic, agricultural, and human health risk assessments. 40 groundwater samples (28 open wells and 12 bore wells) were collected during pre-monsoon 2022 and analyzed by employing multivariate statistics, standard scatter plots, irrigation indices, and health risk assessment. The results of hydrogeochemical analysis and multivariate statistics affirmed that electrical conductivity (EC), total dissolved solids (TDS), calcium (Ca2+), and magnesium (Mg2+) have controlled the hydrochemistry of RIE. Cadmium (Cd) at 46% and chromium (Cr) at 33% have contaminated the groundwater in the study area, making it unsuitable for human consumption and irrigation. The agricultural indices analysis results show groundwater quality ranging from very poor to unsuitable making it unsuitable and also affects crop productivity. Hazard index (HI) results infer that Cr and Cd severely contaminated the RIE's groundwater, encompassing 14 villages, making the groundwater unfit for drinking, domestic use, and irrigation. Hazard quotient (HQ) and incremental lifetime cancer risk (ILCR) analysis revealed that 2 in 100 infants and 3 in 1000 people over the age of 63 are likely to develop cancer due to Cr and Cd in the REI. This is a need-of-the-hour problem, addressing this issue with preventive measures to ensure the protection of groundwater sources will lead to achieving the Sustainable Development Goal 6 (Clean Water and Sanitation).

Assessment of heavy metal contamination in groundwater from motorized boreholes in Maitumbi, Tipa Garage Area, Minna, Niger State

Discharged industrial effluent poses a significant threat to groundwater due to potential heavy metal contamination. Elevated levels of heavy metals in drinking water pose serious public health risks. This study aimed to assess the quality of drinking water from motorized boreholes in Maitumbi, Tipa Garage Area, Minna, Niger State, by measuring heavy metal concentrations using Atomic Absorption Spectroscopy (AAS) as the analytical tool. Water samples were collected randomly from ten (10) boreholes, and the concentrations of some environmentally common heavy metals (Pb, Cd, Hg, Cu, Ni, and Cr) were determined using an Atomic Absorption Spectrophotometer of PG Instruments Ltd. (Model AA500). The results showed high concentration levels for most of the observed metals, which exceeded the permissible limits by the Nigerian Standard for Drinking Water Quality (NSDWQ) and the World Health Organization (WHO). Generally, the study suggests that the water samples are not safe for drinking directly and recommends some level of tertiary purification to reduce the heavy metal concentration levels to make them safe for drinking.

Health Risk Assessment of Heavy Metal Contamination of Groundwater Around Nnewi Industrial Area, Anambra State, Nigeria

The influence of water quality from boreholes situated around the Nnewi industrial area was evaluated by assessing the heavy metal concentrations and health risks associated with human exposure. Water samples were collected from 16 different boreholes around eight industries at a monthly interval from May – October 2019 and November 2019 – April 2020 to cover the rainy and dry seasons, respectively. Water samples were analyzed for copper (Cu), lead (Pb), iron (Fe), zinc (Zn), chromium (Cr), and arsenic (As) using atomic absorption spectrophotometer (AAS). The results were compared with the World Health Organization (WHO) standards. Data obtained for both seasons indicate Cu had a mean value of (0.268±0.136 mg/L), Pb (0.014±0.013 mg/L), Fe (0.119±0.133 mg/L), Zn (0.572±0.220 mg/L), Cr (0.051±0.011 mg/L), and As (0.013±0.001 mg/L) respectively. All the heavy metal concentrations of the sampled water were within their various WHO permissible limits except As, Cr and Pb. The pollution index of As, Cr and Pb were greater than 1, showing heavy contamination of the water. Carcinogenic risk assessment of water via ingestion and dermal route for Cr and As were above the recommended safe limit of 1×10^-6 which posed a cancer risk. The results show that borehole waters were contaminated with heavy metals in both seasons. It is, therefore, recommended that borehole water from the study areas should be treated before being used for various domestic purposes.

Seasonal assessment of heavy metal contamination of groundwater in two major dumpsites in Sierra Leone

Consumption of water contaminated with heavy metals has serious health consequences and these include hypertension, kidney disease, cancer, anaemia, brain damage, etc. However, groundwater pollution with heavy metals may occur naturally or anthropogenically as a result of water-rock interaction, dumpsite leachate, agricultural activities, or sewage percolation. Therefore, the apportionment of the specific sources of heavy metals to groundwater is vital to prevent and control its pollution to groundwater. The present work assessed thirty-four (34) groundwater samples from the vicinity of the Granvillebrook and Kingtom dumpsites, Freetown, Sierra Leone. The objective of the research was achieved by integrating geospatial, indexical, and multivariate statistical methods. The results showed that heavy metals such as Cu, Cr, Fe, and Mn exceeded the permissible levels in the majority of the groundwaters. As and Pb were below the detection level of the instrument in all the groundwaters analyzed. Seasonal variations revealed that the concentration of heavy metals is relatively higher in the dry season due to the effect of dilution. The heavy metal evaluation index and degree of contamination analyses respectively showed that 16.7 and 41.6% of the groundwaters in the Granvillebrook dumpsite are highly polluted by heavy metals. All the groundwater samples in the Kingtom dumpsites except well KW17 are unaffected by heavy metals. The principal component analysis showed that fuel combustion, brake abrasion, and discharge of municipal and industrial waste from the dumpsites are some of the anthropogenic sources that impact groundwater pollution in the study areas. The findings of this research revealed the urgent need to develop strategies to control and mitigate the occurrences of heavy metals and thus serve as a base for future research in the study areas.

Analysis of Heavy Metal Sources in Groundwater and Assessment of Health Risks: An Example from the Southwest Sub-basin of the Shiqi River

In order to explore the sources of pollution and health risk profile of heavy metal elements in groundwater, 41 sets of representative groundwater samples from the southwest sub-basin of the Shiqi River were examined for 10 heavy metal elements (As, Cr, Cd, Al, Cu, Zn, Ni, Co, Mn, and Hg), and correlation analysis and principal component analysis were used to resolve the possible sources of heavy metal contamination in groundwater in the study area. The concentration characteristics and health risk levels of the 10 heavy metals were assessed using the single-factor contamination index (Pi), the Nemerow comprehensive contamination index (PN), and the health risk model. The results showed that:① the average values of heavy metal elements of the groundwater in the study area all met the limit of the class Ⅲ water standard in the quality standard for groundwater (GB/T 14848-2017); only the maximum value of Al was exceeded, followed by a large variation in the concentrations of Al, Mn, and Cr. The heavy metal element with the largest average contribution was Al (65.74%). ② The results of the single-factor contamination index evaluation showed that only the heavy metal element Al exceeded the cleaning level, and the results of the Nemerow comprehensive contamination index evaluation showed that the study area was basically at low pollution levels, and the quality of groundwater was good. ③ The results of the multivariate statistical analysis showed that Zn, Co, and Mn were from mixed sources consisting of geological formation and domestic waste; Al, As, and Cu were from agricultural sources; Cd, Cr, and Ni were from industrial sources; and Hg came from long-range atmospheric transport. ④ The health risk values for all heavy metals in the study area were within acceptable limits, with higher health risk values for children than for adults from the drinking water route, lower health risk values than in adults from the dermal route, and higher health risk values for heavy metals from the drinking water route than those from the dermal route, indicating that the drinking water route was the main route of exposure to heavy metals.

Study of heavy metal contamination of groundwater and surface water near Erdenet ore mining

In this study, we examined the concentration and spatial distribution of heavy metals in groundwater and surface water around the Erdenet ore mining using the Heavy Metal Pollution Index (HPI). The study was carried out in June and September of 2021. In total, 59 water samples were collected randomly from 20 groundwater and 13 surface water sites. We examined 53 heavy metals in the water samples and compared them with water standards including MNS 0900:2018, MNS 4586:1998, and MNS 4943:2015. As the result, we detected 10 out of 53 heavy metals in groundwater and surface water samples. Concentrations of the heavy metals were relatively different between sites. At sites near the mining zone, mean concentrations of Mn (435 µg/L) and Mo (936 µg/L) were above the highest permissible values of the MNS 0900:2018 standard but As (1.30 µg/L) and U (4.65 µg/L) were below the permissible values of the standard. For the groundwater sites, mean concentration of the Sr (1520 µg/L), Cd (0.43 µg/L) and Ni (4.89 µg/L) were below the permissible value of the MNS 0900:2018 standard. 72.2 percent of the total surface water sites were considered at medium to high risks or ecologically risky by the HPI. Hence, we conclude that the Erdenet ore mining area is polluted by heavy metals and further assessment of the environmental status is necessary to evaluate ecological risk. 
 Эрдэнэтийн уурхай орчмын газрын доорх болон гадаргын усны хүнд металлын бохирдлын судалгаа 
 ХУРААНГУЙ
 Энэхүү судалгааны ажлаар бид Эрдэнэтийн зэсийн үйлдвэр орчмын газрын доорхи болон гадаргын усан дахь хүнд металлын элементийн агууламжыг тодорхойлж, тархалтын зураглалыг хүнд металлын бохирдлын түвшний индекс (HPI) ашиглан боловсруулав. Судалгааны ажлыг 2021 оны зун (6-р сар) болон намар (9-р сар) хийж гүйцэтгэлээ. Усны чанарын судалгааны ажлын хүрээнд нийт 59 сорьцыг санамсаргүйгээр гадаргын усны 13, газрын доорхи усны 20 цэгээс авч шинжилсэн. Бид усны хүнд металлын үр дүнд боловсруулалт хийхдээ 53 хүнд металлыг тодорхойлж, MNS 0900:2018, MNS 4586:1998 болон MNS 4943:2015 стандартуудтай тус тус харьцуулсан. Судалгааны дүнд бид 53 хүнд металлаас 10-ийг гүний болон гадаргын усны дээжинд илрүүлсэн. Хүнд металлын агууламж цэг хооронд харьцангуй ялгаатай байв. Үйлдвэрийн бүсэд байрлах хэд хэдэн цэгт Mn (435 мкг/л) болон Mo (936 мкг/л)-ны дундаж агууламж холбогдох стандарт (MNS 0900:2018)-ын зөвшөөрөгдөх дээд хэмжээнээс өндөр агууламжтай байсан бол As (1.30 мкг/л) болон U (4.65 мкг/л) стандартад заасан хэмжээнээс бага агууламжтай байв. Харин газрын доорхи усан дахь Sr (1520 мкг/л), Cd (0.43 мкг/л) болон Ni (4.89 мкг/л)-ийн дундаж агууламж MNS 0900:2018 стандартаас бага байна. Судалгаанд хамрагдсан гадаргын усны цэгийн 72.2% нь HPI индексээр дундаас өндөр эрсдэлтэй буюу экологийн хувьд эрсдэлтэй гэж үзэхээр байна. Эндээс дүгнэхэд үйлдвэрийн район орчмын ус нь хүнд металлаар бохирдсон байгаа тул түүний экологийн эрсдэлийг үнэлэхэд цаашид байгаль орчны төлөв байдлын үнэлгээ шаардлагатай.
 Түлхүүр үгс: Эрдэнэтийн уурхай, хүнд металл, хүнд металлын бохирдлын түвшний индекс газрын доорх ус, гадаргын ус

Groundwater contamination status in Malaysia: level of heavy metal, source, health impact, and remediation technologies.

Groundwater is defined as water that exists underground in voids or gaps in sediments and is extracted for human consumption from aquifers. It is critical to our daily lives because it contributes to the sustainability of our natural ecosystem while also providing economic benefits. Heavy metals are metallic compounds with a relatively high atomic weight and density compared to water. In Malaysia, heavy metal contamination of groundwater has become a concern due to rapid population growth, economic development, and a lack of environmental awareness. Environmental factors or their behaviors, such as density, viscosity, or volume, affect the distribution and transportation of heavy metals. The article discusses the difficulties created by the presence of heavy metals in groundwater supplies and the resulting health problems. Additionally, remediation methods are discussed for managing contaminated water to preserve the ecological environment for current and future generations, as well as their advantages and disadvantages.

Carcinogenic and non-carcinogenic health risk assessment of heavy metals contamination in groundwater in the west of Minia area, Egypt

Groundwater contamination by heavy metals is a worldwide serious issue due to its severe risks to human health. In the present study, a total of 49 groundwater samples were collected and analyzed for eleven trace elements (Al, Cr, Cd, As, Zn, Se, Sn, Ni, Pb, Mn, and Cu) in the west of Minia area, Egypt, to determine groundwater contamination by heavy metals and their impact on groundwater use for drinking and human health as a result. Multivariate statistics, geospatial mapping, and health risk assessment approaches are used to evaluate the potential non-carcinogenic and carcinogenic hazards in the research area and determine both natural and anthropogenic consequences of identified trace elements on local groundwater quality. The heavy metal concentrations (in µg/l) in the groundwater samples were found to be in the following order: Zn (154.5) > Al (40) > As (37.4) > Sn (32) > Cr (28.4) > Hg (25.6) > Cu (21.8) > Cd (16) > Ni (15.4) > Pb (6.5). Heavy metals measurements revealed that As, Hg, and Cu do not meet WHO Guidelines Values, indicating a risk to human health from the consumption of groundwater. Zn > Al > As > Sn > Cr > Hg > Cu > Se > Cd > Ni > Pb was shown to be the order of the mean values of chronic daily heavy metal consumption for new-borns, children, and adults. Continuous oral intake of groundwater loaded with heavy metals could result in carcinogenic and non-carcinogenic concerns, posing serious health dangers to people throughout the life course.

Human health risk hazards by heavy metals through consumption of vegetables cultivated by wastewater

Need for irrigated agriculture is rising daily, but quality water for irrigation is on the decline, necessitating the use of urban wastewater as alternative source, particularly in low or middle income countries. This study assessed the effect of urban wastewater irrigation on the quality of groundwater, soil and vegetables in farms around Faisalabad, Pakistan. Human health risks of heavy metals were investigated through consumption of wastewater irrigated vegetables. Samples of soil, vegetables and water were obtained and analyzed for heavy metal concentrations (cadmium, Cd; lead, Pb; manganese, Mn; nickel, Ni; cobalt, Co; and zinc, Zn). The groundwater could be declared safe for consumption in the present state, as concentration of heavy metals standards. But wastewater-irrigated vegetables had higher Pb, Cd and Mn than the permissible limits. In wastewater-irrigated vegetables, highest HRI-Pb was recorded in mustard leaf and cabbage and was >1. EF for Zn and Mn in all vegetable plants, Ni in potato and cauliflower, Pb in mustard leaf and cabbage were >1.5, suggesting that the metals were generated by anthropogenic processes (such as wastewater irrigation). Long-term irrigation of farmlands with the wastewater will result to heavy metal contamination of groundwater, soil and vegetables in the study area. Therefore, strategies to save the groundwater from future contamination are necessary.

Heavy metal assessment of groundwater quality in part of Karu, Central Nigeria

Abstract Assessment of groundwater quality remains essential in water management; anthropogenic practices such as industrial and agricultural activities can have negative impacts on groundwater quality. The present study assessed heavy metal contamination of groundwater in Karu, Central Nigeria. Heavy metal was evaluated by the indices: degree of contamination, heavy metal pollution and evaluation. Groundwater was found to be significantly contaminated with heavy metal concentrations exceeding the WHO limit for drinking water, particularly around areas of poultry farming, dumpsite and dimension stone quarry and processing plant. Groundwater is therefore considered unsafe for not only drinking purposes but also poultry. Strong correlation was observed between the degree of contamination and heavy metal evaluation index; between Pb, Fe and all indices; between TDS and Pb; Pb and Fe, Fe and Zn, Zn and Cu, Ni and Cu/Zn. The elements Pb, Zn, Cu, Fe and Ni contribute significantly to the contamination observed relative to the others. Groundwater contamination is attributed to anthropogenic activities within the study area; therefore, waste disposal practices require modification. The study presents a case for environmental (both baseline and impact) assessment and continuous monitoring to control pollution of groundwater.

Duckweed: a potential phytosensor for heavy metals.

Globally, heavy metal (HM) contamination is one of the primary causes of environmental pollution leading to decreased quality of life for those affected. In particular, HM contamination in groundwater poses a serious risk to human health and the potential for destabilization of aquatic ecosystems. At present, strategies to remove HM contamination from wastewater are inefficient, costly, laborious, and often the removal poses as much risk to the environment as the initial contamination. Phytoremediation, plant-based removal of contaminants from soil or water, has long been viewed as an economical and sustainable solution to remove toxic metals from the environment. However, to date, phytoremediation has demonstrated limited successes despite a large volume of literature supporting its potential. A key aspect for achieving robust and meaningful phytoremediation is the selection of a plant species that is well suited to the task. For the removal of pollutants from wastewater, hydrophytes, like duckweed, exhibit significant potential due to their rapid growth on nutrient-rich water, ease of collection, and ability to survive in various ecosystems. As a model for ecotoxicity studies, duckweed is an ideal candidate, as it is easy to cultivate under controlled and even sterile conditions, and the rapid growth enables multi-generational studies. Similarly, recent advances in the genetic engineering and genome-editing of duckweed will enable the transition from fundamental ecotoxicity studies to engineered solutions for phytoremediation of HMs. This review will provide insight into the suitability of duckweeds for phytoremediation of HMs and strategies for engineering next-generation duckweed to provide real-world environmental solutions.

Evaluation of heavy metal contamination and human health risk using geo-statistical techniques in selected shallow hard rock aquifers of southwest India

Groundwater is a vital natural resource for drinking and irrigation purposes in India. Heavy metal contamination in groundwater is a global concern and leads to potential health risks to humans and the ecosystem. The aim of this study is to evaluate heavy metal contamination and human health risk in hard rock aquifers of southwest India. Groundwater samples were collected from open wells during the pre-monsoon and monsoon seasons. Heavy metal analysis was conducted using ICP-MS. Geostatistical interpolation technique was applied for spatial analysis. The results revealed that north-west region of the study area have a significant concentration of heavy metals in both the seasons due to intensive agricultural activity. Human health risk assessment in the study area revealed that children are more prone to health risks than adults and infants. Further, this study suspects moderate risk to the groundwater dependent ecosystem. Factor analysis indicates that heavy metals present in groundwater were derived from both geogenic and anthropogenic factors during both seasons. The study concludes that regular monitoring of groundwater is essential to control heavy metal contamination from anthropogenic activities. The heavy metal data obtained from this study can be a valuable database for decision makers to choose the areas of concern, for future water management plans.

Environmental and Health Risks Posed by Heavy Metal Contamination of Groundwater in the Sunan Coal Mine, China.

Groundwater is often used for domestic and irrigation purposes, even in mining areas. Mine drainage, rainfall, and infiltration cause heavy metal enrichment, adversely affecting the groundwater and harming human health. In this study, water samples (October 2021) in the Suzhou southern coal mining area were analyzed for the heavy metals As, Cr, Cu, Fe, Mn, Pb, and Zn to determine potential effects of heavy metal contamination on environmental quality and human health. It was found that 22% and 31% of the sampling sites had “excellent” and “good” water quality, respectively. Excessive concentrations of Fe and Mn were detected in 47% and 72% of the samples, respectively. The non-carcinogenic health risk values of As, Cr, Cu, Fe, Mn, Pb, and Zn were below the negligible levels of health risk set by various environmental agencies. Content ranking was as follows: Fe > Mn > Cr > Cu > Pb > Zn > As, with Fe accounting for 43%. All sampling points exceeded the maximum acceptable level of Cr recommended by the agencies. Chromium, the major carcinogenic factor in the study area, contributed to 95.45% of the total health risk. Therefore, the authorities in this region must closely monitor three heavy metal elements—Fe, Mn, and Cr.

Natural and anthropogenic origin of metallic contamination and health risk assessment: A hydro-geochemical study of Sehwan Sharif, Pakistan

Heavy metal contamination in groundwater is a serious threat to the environment and therefore its proper monitoring is a matter of great concern these days. In the present research, groundwater samples from Sehwan Sharif district Jamshoro, Pakistan were collected to estimate the concentration of various elements including potentially hazardous metals. Statistical analysis of the collected data based on Pearson co-relation metal clustering and Principal Component Analysis (PCA) divides the elements into three groups; Group I contains As, Cu, Ni, and Cd, Group II contains Mn, Fe, B, and Cr and Group III contains Pb and Zn. The elements Cu, Ni, As, Pb, Cd, and Zn found with higher RSD values demonstrate their anthropogenic origin whereas the lower concentration of Mn, Fe, B, and Cr indicate their natural origin (Tepanosyan et al., 2016). The histograms and box-plots of Mn, Fe, B and Cr were found normally distributed while abnormal for Cu, Ni, Pb, As, Cd and Zn. The HQs of these elements indicate their non-carcinogenic risks. However, results of individual metallic behavior indicate the highest HQ measured for B followed by HQs for Cu, and As. The toxic effects of investigated metal (loid)s calculated using HI were found to be 1.58 for adults and 1.35 for the child which is considered the medium chromic risk and cancer risk. About the toxicity of these heavy metals, their cancer risk was assessed on the levels of Cd, As, and Cr in groundwater. The carcinogenic risk of As was found to be 2.78 × 10−4 and 1.62 × 10−3 for child and adult, respectively. Furthermore, the values of this carcinogenic risk are 2.64 × 10−6 and 1.54 × 10−5 for Cd while 4.24 × 10−3 and 2.48 × 10−2 for Cr in child and adult, respectively.Since cancer risk exceeded the target risk of 1 × 10−4 for As and Cr in adults and children, it can thus be considered ‘non-acceptable’. The Geographic Information System (GIS) based maps were prepared using Inverse Distance Weighted (IDW) interpolation which showed the Spatial distribution of all elements throughout Sehwan Sharif from different sources of environment. Spatial maps of elements produced by ArcGIS show the hotspots of potentially hazardous elements such as the highest concentration of Pb, As, Zn, Cu, Ni, and Cd were found in urban areas of Sehwan Sharif district Jamshoro, Pakistan.

Spatial distribution and seasonal variation of heavy metal contaminants and pollution indices in a coastal landmass of Kerala, peninsular India

ABSTRACT Heavy metal contamination in groundwater is a global health concern and its gravity is higher in India, as more than 80% of the rural and 50% of the urban population rely on it for drinking purposes. The present study comprehensively analysed the source, distribution pattern, and seasonal flux of heavy metals in the groundwater sources of Malappuram district, a coastal landmass in peninsular India, using multivariate statistics, pollution indices, and interpolation models in GIS. In three seasons, higher incidences of Pb, Ni and Cd and lower persistence of Zn and Cu were observed during the study period. Heavy metal Pollution Index (HPI) was highest during the pre-monsoon season as 57.57% of the samples were above the critical value. The Metal Index (MI) was higher in coastal areas and is linked to fluvial deposits. More than 77% of the samples were noted to be acidic in all the seasons due to geogenic influxes that accelerated the dissolution of toxic metals upon contact. The HPI interpolation model reveals less heavy metal contamination in the coastal plains, compared to midland and highland urban centres, indicating the least influence of terrain characteristics in the translocation of heavy metals in the groundwater sources.

Contamination of groundwater with heavy metals and its impact on soil and plants – A review

Heavy metals are naturally occurring compound elements that exist in many forms in the environment and the Earth’s biosphere. It is any metallic chemical element with a high density that is hazardous or dangerous at tiny concentrations. Mercury (Hg), lead (Pb), arsenic (As), copper (Cu), and nickel are examples of heavy metals (Ni). These elements are mostly found in water and soil. These natural elements are created by the weathering of parent materials and should occur as a result of human actions. Heavy metal contamination is a severe issue due to its toxicity and ease of propagation in the biotic world. It also has serious consequences for animals, soils, crops, and humans. In this work, we will primarily examine heavy metal contamination in groundwater and its impact on soil. These elements are beneficial to both plants and humans, but exceeding the safe limit generates pollution and has a negative impact on the ecosystem. Heavy metal contamination in soil degrades land and poses a risk to soil and plant growth.

Extracellular Polymeric Substances Facilitate the Adsorption and Migration of Cu2+ and Cd2+ in Saturated Porous Media.

Heavy metal contamination in groundwater is a serious environmental problem. Many microorganisms that survive in subsurface porous media also produce extracellular polymeric substances (EPS), but little is known about the effect of these EPS on the fate and transport of heavy metals in aquifers. In this study, EPS extracted from soil with a steam method were used to study the adsorption behaviors of Cu2+ and Cd2+, employing quartz sand as a subsurface porous medium. The results showed that EPS had a good adsorption capacity for Cu2+ (13.5 mg/g) and Cd2+ (14.1 mg/g) that can be viewed using the Temkin and Freundlich models, respectively. At a pH value of 6.5 ± 0.1 and a temperature of 20 °C, EPS showed a greater affinity for Cu2+ than for Cd2+. The binding force between EPS and quartz sand was weak. The prior saturation of the sand media with EPS solution can significantly promote the migration of the Cu2+ and Cd2+ in sand columns by 8.8% and 32.1%, respectively. When treating both metals simultaneously, the migration of Cd2+ was found to be greater than that of Cu2+. This also demonstrated that EPS can promote the co-migration of Cu2+ and Cd2+ in saturated porous media.

Assessment of heavy metal contamination in groundwater of Diyarbakir Oil Production Area, (Turkey) using pollution indices and chemometric analysis

Assessment of heavy metal contamination in groundwater of Diyarbakir Oil Production Area, (Turkey) using pollution indices and chemometric analysis

Human health risk of heavy metal contamination in groundwater and source apportionment

Human health risk of heavy metal contamination in groundwater and source apportionment