Heavy Metal Contamination In Groundwater Research Articles

Assessment of heavy metal contamination in groundwater and its implications for dental and public health

Groundwater contamination with heavy metals is a critical environmental issue, especially in regions heavily reliant on groundwater for drinking purpose. These metals can seep into groundwater from soil and rock weathering or through improper disposal of industrial waste and effluents. Access to safe drinking water is essential for maintaining public health. This study aimed to assess heavy metal contamination in groundwater and its implications for dental and public health. The objective of the study was to measure the concentration of the heavy metals in the dentine of extracted tooth of the study population. The study concurrently measured heavy metal concentrations in groundwater and tooth dentine samples, analyzing demographic profiles, heavy metal correlations, and underlying structures using Principal Component Analysis (PCA). The average level of heavy metals in the groundwater samples varied from 9.763 ± 3.362 μg/L for Cd to 3426.204 ± 875.264 μg/L for Fe. The mean concentrations (μg/g) in teeth dentine showed significant variations, with iron (Fe) ranging from 0.149 ± 0.03 μg/g in water purifiers to 4.62 ± 0.578 μg/g in local water sources. Similar variations were observed for other heavy metals across different water sources. Principal component analysis (PCA) revealed seven principal components, with the first two components explaining 96.1% of the total variance. The findings revealed varied concentrations of heavy metals across all water sources. Statistical analyses underscored the complex relationship between water sources and heavy metal contamination levels, highlighting the need for targeted interventions to improve water quality and mitigate health risks. The study highlights the urgent need for monitoring and mitigation efforts to ensure safe drinking water and mitigate health risks associated with heavy metal contamination.

Health risk assessment of toxic metals and DNA damage in somatic and germ cells by soil and groundwater of a major cement factory in Nigeria.

The waste generated from cement manufacturing is an important source of heavy metal contamination of groundwater and soil. This study investigated the concentration of toxic metals in the soil of a major cement factory and nearby groundwater. Ecological and carcinogenic risks of the metals were calculated. Potential reproductive toxicity and genotoxic effects of the samples were assessed in sex and somatic cells of male mice using sperm abnormalities and bone marrow micronucleus (MN) assays, respectively. Also, the serum ALP, ALT, AST, Total Testosterone (TT), Luteinizing Hormone (LH), and Follicle Stimulating Hormone (FSH); and liver SOD and CAT activities were measured in the treated mice. Cr, Cu, Ni, Zn, Mn, Cd, and Pb levels in the soil and groundwater exceeded the allowable maximum standard. Ingestion and dermal contact were the most probable routes of human exposure with children having about three times higher probability of exposure to the metals than the adults. Ni, Pb, and Cr presented carcinogenic risks in children and adults. In the MN result, nuclear abnormalities in the studied mice especially micronucleated polychromatic erythrocytes increased significantly (p < 0.05). Compared to the negative control, the ratio of PCE/NCE showed the cytotoxicity of the two samples. Data further showed a significant increase in the serum ALP, AST, and ALT while the liver CAT and SOD activities concomitantly decreased in the exposed mice. Sperm morphology result showed that the samples contained constituents capable of inducing reproductive toxicity in exposed organisms, with alterations to the concentrations of TT, LH, and FSH. Toxic metal constituents of the samples were believed to induce these reported reproductive toxicity and genotoxic effect. These results showed the environmental pollution caused by cement factory and the potential effects the pollutants might have on exposed eukaryotic organisms.

Assessment of heavy metal contamination in groundwater of rural areas of Kurdistan Province Iran: A comprehensive study

This study focuses on the contamination of groundwater by heavy metals (HMs) in the Kurdistan Province of Iran, an area heavily reliant on these water resources, especially in rural regions. This research aimed to quantify the concentrations of 20 HMs in groundwater sources and assess the associated health risks, including both carcinogenic and non-carcinogenic effects, for different age groups. The study was conducted in 2024. We collected 155 groundwater samples from water resources of the villages in Kurdistan Province, west of Iran. The study encompassed comprehensive sampling of groundwater from various wells and springs throughout the province, which was subsequently subjected to thorough laboratory analysis utilizing Inductively Coupled Plasma Mass Spectroscopy (ICP-MS) for the quantification of heavy metal (HM) concentrations. The highest concentrations of As, Co, Cu, and Mo were 7.90, 0.22, 2.48, and 1.68 μg/l, respectively. It was related to the cities of Qorveh, Sanandaj, Baneh, and Qorveh respectively. A Health Risk Assessment (HRA) was performed, indicating that, while the concentrations of most HMs were within the thresholds established by national and international standards, certain metals, such as arsenic and lithium, presented notable non-carcinogenic risks, especially to children. These metals were responsible for over 48 % of the cumulative hazard index (HI) across all ten cities evaluated. Furthermore, the HI for the adult demographic exceeded 1.0 (specifically 1.23) exclusively in Qorwe city. The study also identified a high carcinogenic risk associated with lead across the province, which has a carcinogenic risk of 7.3 × 10−03 in 10 studied cities, which is more than the guideline value of 10−04. The findings underscore the urgent need for continuous monitoring and the implementation of preventive measures to safeguard public health. The results provide crucial insights for policymakers and health authorities, facilitating informed decisions to mitigate the health risks posed by HM contamination in the region's groundwater.

Investigating Heavy Metal Contamination in Groundwater of Agricultural Areas: The Case Study of Shekhan, Duhok, Iraq

Investigating Heavy Metal Contamination in Groundwater of Agricultural Areas: The Case Study of Shekhan, Duhok, Iraq

Evaluating monsoon season heavy metal contamination in groundwater of Uttar Dinajpur District using pollution indices and Principal Component analysis

Heavy metal contamination in groundwater poses significant environmental and public health challenges globally. This study investigates the presence and distribution of heavy metal contamination in groundwater within Uttar Dinajpur District, India, focusing on zinc (Zn), manganese (Mn), copper (Cu), iron (Fe), and lead (Pb). Groundwater samples were collected and analysed for heavy metal concentrations, and statistical analyses, including descriptive statistics, histograms, box plots, Heavy Metal Pollution Index (HPI) analysis, Metal Index (MI) analysis, and Principal Component Analysis (PCA), were conducted to assess contamination levels, spatial distribution, and potential sources. Results indicate varying levels of heavy metal contamination across the district, with manganese, iron, and lead frequently exceeding permissible limits, posing potential health risks. The PCA revealed common sources and relationships among heavy metals, aiding in understanding contamination patterns. The study underscores the importance of continuous monitoring and targeted interventions to manage heavy metal contamination in groundwater, emphasizing the need for further research to develop effective mitigation strategies.

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 the groundwater of Gujarat 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 paper 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 the groundwater of Gujarat.

Assessment of Heavy Metal Contamination of Groundwater in Rural Areas of Duhok City, Iraq

This study investigates the quality of groundwater sources in the rural areas of Duhok City, Iraq, with a particular focus on heavy metal contamination, chemical composition, and properties of water. Water samples from 14 wells, serving as the main water source for the surrounding areas, were collected and analyzed. Water quality parameters including calcium (Ca²⁺), magnesium (Mg²⁺), chloride (Cl⁻), potassium (K⁺), and sulfate (SO₄²⁻) values ranged from 24 to 105.6 mg/L, 6.832 to 50.752 mg/L, 18 to 34 mg/L, 1 to 7 mg/L, and 3.4 to 38 mg/L respectively. Common heavy metals like manganese (Mn), lead (Pb), copper (Cu), and cobalt (Co) exhibited varying concentrations. Most parameters meet the WHO standards, except for the elevated potassium in one sample, requiring attention. Additionally, 50% of the sampled wells showed elevated cadmium (Cd) levels. Possible sources of contamination include industrial activities, agricultural runoff, and geological factors, highlighting the importance of ongoing monitoring and targeted interventions to ensure access to clean and safe water.

Health risk assessment due to heavy metal contamination in groundwater of Basuhi River Basin, Jaunpur, India

Health risk assessment due to heavy metal contamination in groundwater of Basuhi River Basin, Jaunpur, India

Characterization of heavy metal contamination in groundwater of typical mining area in Hunan Province

Heavy metal pollution in mining areas is a major cause of groundwater contamination, characterized by high toxicity, difficult degradability, and easy accumulation, and the source of pollution is not easily identified. Relying on the results of groundwater quality analysis tests in a typical mining area, this paper uses the SPSS 18.0 statistical analysis model to analyze the statistical characteristics of different indicator factors in the antimony mining area. The conclusions play a crucial role in implementing health and safety measures for the mining area and its surrounding residents. The statistical study results show that Mn, Se, As, and Sb are closely related to human mining activities and are polluted to varying degrees; the principal component analysis model indicates that the upstream monitoring points 26#, 22#, and 25# in the mining area groundwater are less polluted. The five monitoring points with a comprehensive principal component F > 1 are all located within the range of the metal mine cluster, indicating that the groundwater in the mining area is particularly sensitive to the impact of anthropogenic mineral extraction. This research summarizes the hydrogeological and geochemical statistical characteristics of the groundwater in the mining area, providing a reference for groundwater pollution risk diagnosis, ecological restoration, and heavy metal pollution prevention and control in this and similar mining areas.

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. &#x0D; Эрдэнэтийн уурхай орчмын газрын доорх болон гадаргын усны хүнд металлын бохирдлын судалгаа &#x0D; ХУРААНГУЙ&#x0D; 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.&#x0D; 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.