Heavy Metal Contamination Of Vegetables Research Articles

Effects and remediation of heavy metals contamination in soil and vegetables from different areas: A review

Heavy metals are non-biodegradable and thus persist in the environment, potentially infiltrating the food chain via crop plants and accumulating in the human body through biomagnification. Due to their toxic nature, heavy metal poisoning poses a severe threat to human health and the environment. Consuming vegetables contaminated with heavy metals can lead to increased accumulation of these metals in the human body. This review discusses the risks of heavy metal contamination in various areas, as reported in some research studies, and the implications for human health. Data obtained from several journals indicated that levels of lead (Pb) and cadmium (Cd) in vegetables were generally within permissible limits, though cadmium concentrations were found to be low in some studies. High concentrations of lead (Pb) can affect metabolic functions, growth, and photosynthetic activities. Cadmium (Cd) levels, which are lower than the permissible limit of 0.2 mg kg−1 set by WHO, can lead to chromosomal aberrations and sister chromatid exchanges in cells. Zinc (Zn) levels were within permissible limits except in lettuce and spinach in some findings. Low zinc content in vegetables impacts human health, plant health, and agricultural productivity. Addressing zinc deficiency requires integrated approaches such as soil management, crop biofortification, and dietary diversification. Ensuring adequate zinc levels is essential for improving public health and achieving sustainable agricultural practices. Addressing heavy metal contamination in vegetables requires a combination of remediation and preventive strategies. Implementing soil and water management practices can mitigate these risks and ensure the safe production of vegetables.

Heavy Metal Contamination Risks in Environmental and Vegetable Samples around a Metal Workshop in Kofar Marusa, Katsina Metropolis

Study’s Novelty/Excerpt This study focuses on the health risks associated with heavy metal contamination in vegetables irrigated near a metal workshop in Kofar Marusa, Katsina Metropolis. By quantifying the concentrations of various heavy metals in commonly consumed vegetables, the research shows significant variations in metal uptake among different vegetable types, with cress and spinach posing the highest health risks. The study uses Health Risk Index (HRI) and Target Hazard Quotient (THQ) calculations to show the potential health hazards, particularly for children, highlighting the need for targeted interventions to mitigate these risks in affected communities. Full Abstract Heavy metal contamination from Metal workshop activities poses health risks by accumulating in crops and entering the food chain. This study quantified heavy metal concentrations and health risks in commonly consumed vegetables irrigated near a metal workshop in Kofar Marusa, Katsina Metropolis. Samples from the cultivation areas of Cabbage, lettuce, tomatoes, spinach, and cress were analyzed. After acid digestion, the amounts of heavy metals were measured by Atomic Absorption Spectrometry. Copper (0.123 mg/kg), manganese (0.431 mg/kg), and nickel (0.539 mg/kg) were greatest in spinach. Manganese (0.374 mg/kg) and cobalt (1.474 mg/kg) levels were higher in cress. Lettuce had the highest iron concentration (6.028 mg/kg) and the lowest metal levels. Lead (11.68 mg/kg) and chromium (2.276 mg/kg) were both high in Cabbage, and nickel (0.526 mg/kg) and lead (4.24 mg/kg) were noteworthy in tomatoes. Among the Health Risk Index (HRI) calculated, cress reached 17.967 for adults. Children's exposure to heavy metals for Cobalt (Co) and Lead (Pb) through cabbage consumption showed the Target Hazard Quotient (THQ) values for Co (0.089) and Pb (0.036), significantly higher than those for adults. The Cumulative Lifetime Cancer Risks showed that Cress posed the highest risk for both adults and children, followed by spinach. The study revealed significant variations in heavy metal concentrations taken up among different types of vegetables, portraying potential health risks associated with its consumption. It also suggested that the consumption of vegetables cultivated through irrigation near the metal artisanal site may contribute to the bioaccumulation of heavy metals burden among the population. The study brought to light the wide range of heavy metal uptake in vegetables as well as the possible health hazards associated with eating produce grown close to the metal workshop.

Health risk assessment associated with consumption of heavy metal-contaminated vegetables: A case study in the southern area of Northeast Thailand

This study aims to determine the amount of lead exposure and investigate the health hazards linked to the consumption of leafy vegetables contaminated with lead and cadmium. It focuses on a specific case study conducted in the southern region of Northeast Thailand. Five types of leafy vegetables, including Chinese kale, cabbage, Chinese cabbage, lettuce, and parsley, were collected from the Southern Northeast region of Thailand. The vegetable consumption of 3,831 individuals was calculated. The results showed that Chinese kale had the highest average lead contamination (0.009±0.015 mg/kg DW), followed by Chinese cabbage (0.005±0.01 mg/kg DW), cabbage (0.004±0.003 mg/kg DW), lettuce (0.003±0.003 mg/kg DW), and parsley (0.001±0.01 mg/kg DW), respectively. The evaluation results indicated that the margin of safety values for leafy vegetable consumption ranged between 4.49731E-05 and 0.04550, suggesting no major health risks. Based on geographical information, the lowest altitude was 95 m in the Warin Chamrap District of Ubon Ratchathani Province, while the highest was 450 m in the Pak Chong District of Chum Klat, Nakhon Ratchasima Province. Therefore, people in the Southern Northeast region of Thailand should be encouraged to cultivate vegetables for their own consumption based on the season, and hydroponic systems should be utilized. It is important to assess and monitor the levels of heavy metals in the vegetables intended for consumptions and potential adverse effects on the environment and, consequently, human health. When choosing vegetables, it is advisable for consumers to exercise prudence and choose produce sourced from reputable cultivation facilities. Additionally, to prevent the accumulation of pollutants that could result in long-term health effects, it is prudent to vary their vegetable intake. The data obtained can be used in remediation techniques and to implement control measures for heavy metal contamination in vegetables.

Nanoremediation approaches for the mitigation of heavy metal contamination in vegetables: An overview

Abstract Metals with high atomic weights and gravity are considered heavy metals (HMs). Rapid industrialization increases the content of harmful HMs in an ecosystem by affecting soil, water, and living organisms. One growing concern is a buildup of HMs in food crops including vegetables either by irrigation with wastewater containing HMs or from contaminated soil. Consumption of vegetables has potentially serious effects on living organisms. Various physical and chemical strategies are used but such methods have certain limitations. Nanoremediation, a combination of bioremediation and nanotechnology. represents an innovative way for sustainable removal of contaminants such as HMs. Nano-level understanding of cellular and molecular pathways is essential for treating HMs. Although the eco-toxicity of nanotechnology is a recent issue of concern, it is a promising strategy to deal with the pollution of the environment. These strategies can make the vegetables consumable with fewer HMs. Nanoparticles (NPs) are potentially adaptable for both in situ and ex situ HM treatment. This review provides a critical overview of recent nanoremediation technologies and the properties of NPs. Furthermore, considerable valuation of nanoremediation techniques was considered for dealing with contamination with special attention on health and the environment. The review further illustrates the ecological implementation of nanotechnology and provides a strong recommendation for the utilization of nanoremediation to improve the recent situation and justifiable future.

Risk of Heavy Metal Contamination in Vegetables Fertilized with Mushroom Residues and Swine Manure

Mushroom residues and swine manure are two common types of agricultural waste that are often returned to fields as organic fertilizers. However, the environmental risks of their reclamation, such as heavy metal pollution, have been less studied. To investigate the potential risks of heavy metal contamination in soils and vegetables after continuously applying mushroom residues and swine manure, field experiments of four consecutive vegetable rotations were conducted in the Qingpu District of Shanghai, Southeast China, from 2019 to 2021. The concentrations of heavy metals in soils continuously fertilized with mushroom residues and swine manure gradually increased. The organic matter content in the soils exhibited a significant correlation with the concentrations of Cu, Zn, Pb, and Cd (p < 0.01), suggesting that the increase in heavy metals is attributed to the use of organic waste. In particular, the application of swine manure increased Cu, Zn, Pb, and Cd concentrations in the soils by 118.3%, 54.9%, 57.6%, and 122.2%, respectively. Moreover, the application of organic waste raised the risk of the bioaccumulation of toxic metals, such as Cd, in vegetables. The Cd concentration was significantly and positively correlated with Zn in the edible parts of vegetables (p < 0.05). The recycling of swine manure more significantly enhanced Cd concentrations in the edible parts of green pepper (Capsicum annuum), eggplant (Solanum melongena), Brassica chinensis, and lettuce (Lactuca sativa), which were 2.53, 1.55, 1.66, and 1.62 times that of the non-fertilizer control (CK), respectively. Although the increase in heavy metals in the soils and vegetables was still mild when compared with the set thresholds of soil and food safety after the four vegetable rotations, the trend of increase in toxic heavy metals in the food chain with a continuous application of organic waste should be carefully considered.

An analysis of heavy metal contamination in vegetables and herbs growing in water hyacinth manure, case of Lake Chivero

The primary goal of this study was to determine concentrations of heavy metals in water hyacinth compost manure (Pb, Cd, Cu, Cr, and N) and their bioavailability in Brassica oleracea var acephala and mentha organs. Analysis also focused on the physiological responses of Brassica oleracea var acephala and mentha to water hyacinth compost.The target was to find if water hyacinth have high nutritive to enhance plant growth and act a an alternative solution for controlling water hyacinth if harvested from eutrophic Lake Chivero. Rhizofiltration ability of water hyacinth makes it potential source of fertilizer to plants since it accumulates all excess nutrients from hyper-eutrophic water sources. Before planting Mentha herb and Brassica oleracea var acephala, soil samples and compost were taken to the laboratory. The experiment was carried out in uncontaminated soil. For eight weeks, mature plants were harvested and their roots, stems and leaves were collected and plant materials were tested for heavy metal concentration to determine total metal concentration. The Bio-concentration Factor was used to calculate the concentration of heavy metals in Brassica oleracea var acephala and Mentha. The heavy metal accumulation rate in Brassica oleracea var acephala was calculated using a translocation factor. Heavy metal concentrations of Pb, Cd, Cu, Cr, and Ni were measured in compost treatments as well as Covo vegetables and mint herbs. Metal concentrations were greater than 1 mg/kg for Pb, Ni, Cu, and Cr, but not for Cd, which was below detection levels. The metals Pb, Ni, Cu, and Cr all had a BCF >1 mg/kg in Brassica oleracea var acephala and Mentha exceeded the WHO food safety guidelines. During the exposure experiments, the concentrations of Pb, Cd, Cu, Cr, and Ni in brassica oleracea var acephala vegetables and Mentha herbs increased. In decreasing order, Brassica oleracea var acephala and Mentha roots and leaves had the highest accumulation and total heavy metal concentration of Pb > Ni > Cu > Cd > Cr. In summary, water hyacinth from Lake Chivero cannot be used as a biofertilizer for food crops hence more research is required on other non-food crops and other uses like bio-fuel.

Heavy metals contamination in vegetables irrigated with wastewater: a case study of underdeveloping regions of Pakistan.

Irrigation of food crops with untreated wastewater leads to the accumulation of heavy metals in their edible parts. Exposure to toxic elements through consumption of contaminated vegetables even at very low concentration is becoming a serious problem for human health in many countries. This issue of heavy metals contamination needs great attention especially in Pakistan where irrigation by wastewater has become a common practice in urban and periurban areas. The present study was conducted to assess the contamination of different heavy metals including nickel (Ni), cadmium (Cd), lead (Pb) and chromium (Cr) in vegetables irrigated with wastewater in different districts of Punjab (Pakistan) like, Faisalabad, Lahore, Gujranwala, Sargodha, Sahiwal, Multan, Rawalpindi and Bahawalpur during years 2016-2019. The maximum contamination factor (Ni, 1.39; Cd, 5.86; Pb, 3.99; Cr, 2.24), pollution load index (2.92) and degree of contamination (13.48) were observed in wastewater irrigated agricultural soils of district Gujranwala as compared to other districts. Mean metal concentration in vegetables grown with untreated wastewater and transfer factor varied with plant type, frequency of irrigation and soils types/series of different districts of Punjab. The highest metal contamination was observed in Gujranwala where 44% vegetable samples were contaminated with Ni, 87% with Cd, 97% with Pb and 88% with Cr. Radar analysis and hierarchical cluster analysis showed that mustard leaves, spinach and lettuce were more contaminated vegetables compared to other vegetables. This study contributes to the evidence-based conclusion that cultivation of vegetable with untreated wastewater should be prohibited and required treatment of wastewater is needed.

Status and health risk assessment of heavy metals in vegetables grown in industrial areas of Bangladesh

ABSTRACT The presence of toxic heavy metals in vegetables is a matter of concern worldwide as they impose significant public health hazards. This study quantified heavy metals such as lead (Pb), cadmium (Cd), chromium (Cr), copper (Cu), and zinc (Zn) in widely consumed vegetables such as red amaranth (Amaranthus cruentus), radish leaf (Raphanus sativus), brinjal (Solanum melongena), spinach (Spinacia oleracea), bottle gourd (Lagenaria siceraria), carrot (Daucus carota), and fenugreek (Trigonella foenum-graecum) grown in Savar industrial areas of Bangladesh to assess human health risks. Atomic absorption spectroscopy (AAS) was used to determine heavy metals in vegetables (n = 96). Studied heavy metals were detected in most vegetable samples, whereas 59.38% and 40.62% of samples contained carcinogenic Pb and Cd higher than the Food and Agriculture Organization (FAO) maximum allowable concentration (MAC). Principle component analysis (PCA) revealed that wastewater irrigation due to anthropogenic activities is the main source of heavy metal contamination in vegetables of the study area. Human health risks were assessed in terms of estimated daily intake (EDI), incremental lifetime cancer risks (ILCR), target hazard quotient (THQ), and hazard index (HI). EDI values of all heavy metals were lower than the corresponding maximum tolerable daily intake (MTDI) values. The ILCR values of Pb in most samples (except fenugreek) for children were found above the threshold value (ILCR> 10−4), indicating carcinogenic health effects from lifetime consumption of these vegetables. The THQs of Pb in sample red amaranth and carrot were greater than 1.0, indicating potential non-carcinogenic risks of consuming contaminated vegetables. The HI values of all heavy metals in red amaranth and carrot >1.0 for adults and children, suggesting health hazards from these samples. This study might help policymakers and concerned authorities to implement a strategic plan for safe vegetable production and minimise the health risks of consuming heavy metal contaminated vegetables.

Heavy metals in vegetables: a review of status, human health concerns, and management options.

For sustainable global growth, food security is a prime concern issue, both quantitatively and qualitatively. Adverse effects on crop quality from contaminants like heavy metals have affected food security and human health. Vegetables comprise the essential and nutritious part of the human diet as they contain a lot of health-promoting minerals and vitamins. However, the inadvertent excess accumulation of heavy metals (As, Cd, Hg, and Pb) in vegetables and their subsequent intake by humans may affect their physiology and metabolomics and has been associated with diseases like cancer, mental retardation, and immunosuppression. Many known sources of hazardous metals are volcano eruptions, soil erosion, use of chemical fertilizers in agriculture, the use of pesticides and herbicides, and irrigation with wastewater, industrial effluents, etc. that contaminate the vegetables through the soil, air and water. In this review, the problem of heavy metal contamination in vegetables is discussed along with the prospective management strategies like soil amendments, application of bioadsorbents, membrane filtration, bioremediation, and nanoremediation.

Health risk associated with heavy metal contamination of vegetables grown in agricultural soil of Siran valley, Mansehra, Pakistan-a case study.

Monitoring of heavy metals in agricultural soils and the crops grown in them is essential to design mitigation strategies to reduce toxic heavy metals in diet and food chains. We determined chromium (Cr), arsenic (As), cadmium (Cd), and lead (Pb) concentrations in the soil-plant system from agricultural fields of Siran Valley, Mansehra, Pakistan, to assess their potential health risk. Although the concentrations of the heavy metals in soils were within the permissible limits for agricultural soils, heavy metal concentrations in many of the vegetables exceeded the recommended safe values. Among the six leafy vegetables tested, all had greater than safe limits for As, four also for Cr and two also for Cd. As level was greater than safe limits in all five fruit and flower vegetables, two had Cr, and one had Pb also at unsafe levels. Among the five tuber, bulb, and root vegetables, As was higher than safe limits in all and Cd in one. The transfer factor in all three categories of vegetables followed the descending order Cd > As > Cr > Pb. Daily intake of metals were within limit set by USEPA for all heavy metals except As. The health risk indices for Cr, As, Cd, and Pb indicated that values greater than 1 for As suggest that the vegetables studied here pose a risk of chronic arsenic poisoning, but other heavy metals do not pose such a risk. Our study reinforces the need for mitigation strategies to reduce unsafe levels of heavy metals in vegetables.

Occurrence and dietary exposure of heavy metals in marketed vegetables and fruits of Shandong Province, China.

The contamination of heavy metals in vegetables and fruits is a serious threat to food safety and human health. The present study was designed to investigate the occurrence and dietary exposure of lead (Pb), arsenic (As), cadmium (Cd), and mercury (Hg) in vegetables and fruits in Shandong Province, China. Results demonstrated that the mean level of total heavy metals was 30.25 µg/kg. The most frequently found heavy metal was Cd (69.2%) with a mean value of 11.54 µg/kg. The mean exposure values of Pb, As, Cd, and Hg in vegetables were 0.052, 0.045, 0.038, and 2.40 × 10–3 µg/kg bw/day, respectively. Moreover, the calculated hazard quotient (HQ) values of mean levels for these four heavy metals were all less than 1, indicating the health risk of heavy metal exposure caused by vegetable consumption was low. This study has displayed baseline information on heavy metal contamination in vegetables and fruits, which can provide useful data support for the formulation of relevant standards and government management.

Heavy metal concentrations in vegetables cultivated and sold in Machakos Municipality, Kenya

Heavy metal contamination of vegetables is a key aspect of food quality assurance since vegetables form a substantial proportion of the daily human diet. Health risks in urban populations due to exposure to heavy metals are on the increase because of the consumption of vegetables irrigated with wastewater. This study analyzed the concentration of Cd, Cu, Pb, Zn and Cr in spinach and kales grown using contaminated water of the Mitheu urban stream and those sold within Machakos municipality. Vegetable samples were collected once per month for a period of four months starting from June to September 2019. The mean heavy metal concentrations obtained were0.013 – 3.19 mg/kg, 0.468 – 1.706 mg/kg, 0.02 – 0.368 mg/kg, 5.78 – 26.7 mg/kg, and 0.104 – 14.0 mg/kg for Cd, Cu, Pb, Zn and Cr respectively in kale samples from the different sampling sites. The heavy metal mean concentrations in spinach were 0.055 – 0.575 mg/kg, 3.79 – 5.55 mg/kg, 0.098 – 1.49 mg/kg, 8.32 – 20.7 mg/kg and 0.368 – 4.43 mg/kg for Cd, Cu, Pb, Zn and Cr respectively. The mean concentrations of Cd, Pb, Zn and Cr in both spinach and kales in some of the sampling sites were above WHO permissible levels for heavy metals in vegetables for human consumption. However, the mean concentration of Cu was below WHO recommended levels. Consumption of these vegetables therefore poses a health risk to the consumers. There is need to create public awareness on the dangers of consuming contaminated vegetables. Additionally, measures to curb heavy metal pollution in Mitheu stream should be taken by the County Government of Machakos.

Heavy Metals Accumulation and Health Risk Consumption in Some Vegetables, Isfahan, Iran

: Heavy metals (HM) can enter the human body via food chains or contaminate groundwater resources. The current study aimed to investigate HM contamination in vegetables and its associated health index risk (HIR) in Isfahan, Iran. The lowest amount of HM was observed for Cd and Pb in all vegetables. The highest level of Cadmium content was found in potato (1.15 mg kg-1 dry matter (DM)) and spinach (1.18 mg kg-1 DM). The highest levels of As and Cu were observed in lettuce, while the lowest content of Cu was in the carrot. Moreover, the highest content of N (344 mg kg-1 DM) was obtained in spinach. The As and P were higher than standard amounts, and HIR was higher than 1 for these two elements. Heavy metal's HIR through ingestion vegetables were a great concern, and there has been particularly increased attention to As. A great understanding of the ecological effects of HM on soils and vegetables is needed to develop management options.

The risk associated with heavy metals contamination in vegetables growing in urban and peri-urban areas

The risk associated with heavy metals contamination in vegetables growing in urban and peri-urban areas

Heavy Metal Contamination in Green Leafy Vegetables Irrigated with Wastewater Collected from Harar Town Vegetable Farm, Ethiopia

Food safety issues are of growing concern to consumers globally because of the risks associated with consumption of foods contaminated with heavy metals. In Harar town, Kebele 05 vegetable farm is known to produce vegetables irrigated with wastewater. To what extent these vegetables are contaminated with heavy metals was not known. Thus, a laboratory based cross sectional study was conducted from October 2016 to January 2017 to assess the extent of heavy metal contamination of vegetables. Accordingly, a total of 72 samples from four leafy vegetables namely lettuce (Lactuca sativa), spinach (Spinacea oleracea), kale (Brassica carinata)) and cabbage (Brassica oleracea) were determined. Lead (Pb), Cadmium (Cd), and Chromium (Cr) concentration was determined using atomic absorption spectrophotometry. In all the vegetables, the mean concentrations of Pb, Cd and Cr were 0.17, 0.62 and 1.78 mg/kg, respectively in all vegetables. Cd was found in level more than the maximum limit recommended by FAO/WHO but the level of lead was within the normal range for all vegetables. Chromium was found also within the normal range in all vegetables except in lettuce. The findings of this study have important information on the implications of public health by sequestration of heavy metals to these leafy vegetables then to among vegetable consumers of Harar town and the surroundings. Thus, it is recommended that the concerned public health authorities need to create awareness in the community and discouraging the use of untreated wastewater for cultivating vegetables. Keywords: Contamination, Heavy metal, Vegetables, Wastewater DOI: 10.7176/FSQM/94-03 Publication date: February 29 th 2020

Ecological risk assessment of heavy metals in vegetables irrigated with groundwater and wastewater: The particular case of Sahiwal district in Pakistan

The use of wastewater for irrigation is a common practice in the developing world. It is a major route of heavy metal contamination in vegetables. The groundwater, an alternative source for irrigation, is under threat of heavy metal contamination due to long-term use of wastewater. The present study investigated heavy metals contamination from irrigation with wastewater compared to groundwater in District Sahiwal situated in the vicinity of Lahore, Pakistan. Irrigated water, soil and vegetables were analyzed for Iron, Nickel, Lead, copper, Cadmium, Manganese and Zinc; Metal transfer factor (MTF); daily intake of metals (DIM) and health risk index (HRI) were calculated. Manganese (Mn) and Cd in wastewater irrigated soil, Pb, Cd, Mn and Fe in wastewater-irrigated vegetables and Pb, Mn and Fe in groundwater-irrigated vegetables exceeded the permissible limits (WHO, 1996), particularly in Mustard and Spinach. Generally, MTF was higher in wastewater than groundwater-irrigated vegetables, particularly with Fe followed by Ni. HRI was higher for wastewater-irrigated than groundwater-irrigated vegetables. Wastewater-irrigated Mustard and Spinach showed a HRI > 1 only for Mn. Quality control mechanisms need to be applied for long-term use of groundwater. Also, treatment of wastewater prior to application to plants must be considered to save crops from contamination.

Heavy metals (Pb, Cd, Cu, Zn, Ni, Co) in leafy vegetables collected from production sites: their potential health risk to the general population in Shiraz, Iran

Heavy metal contamination of vegetables is a great public health concern. One hundred samples of spinach, dill, cilantro, and cress from the production sites of Shiraz, Iran, and its outskirts were, therefore, examined for lead (Pb), cadmium (Cd), copper (Cu), zinc (Zn), nickel (Ni), and cobalt (Co) content. The potential health risks of these metals to local residents via the consumption of leafy vegetables were also estimated. The mean concentrations of Pb, Cd, Cu, Zn, Ni, and Co were 3.21, 0.28, 4.55, 40.44, 3.11, and 1.86mg/kg dry weight, respectively. The Pb level exceeded the permissible limit of 0.3mg/kg in 44.7% of vegetable samples. The other elements were, however, within FAO/WHO standards. The estimated daily intake (EDI) of Pb, Cd, Cu, Zn, Ni, and Co from leafy vegetables was 0.10, 0.01, 0.14, 1.26, 0.10, and 0.06μg/kg body weight/day, respectively. At the mean and 97.5 percentile levels, all health risk index (HRI) values were less than the safe limit (< 1). Thus, within the area this study was focused on, leafy vegetables did not make a major contribution to the dietary intake of the elements which could be mainly attributed to the low vegetable consumption by the study population (20g/day). Nevertheless, the lead content of the vegetables should be viewed with some concern. Regular monitoring of heavy metal contamination of foodstuff is recommended to control the sources of contaminants in the food chain.

Heavy Metal Contamination of Irrigation Water, Soil, and Vegetables in a Multi-industry District of Bangladesh

Heavy metal (Cr, Cu, Zn, As, Cd, and Pb) concentrations in irrigation water, soil, and vegetables were measured to assess the contamination levels in a multi-industry district in Bangladesh. In this district, wastewater discharged from three industrial areas (textile, dye, agrochemical, paint and ceramics factories) was mixed with irrigation water. The Zn, Cu, Pb, and Cr concentrations were high in both irrigation water and soil, and all of these concentrations exceeded the permissible limits except for the Cd and Pb concentrations in irrigation water. Hierarchical cluster analysis of the irrigation water and soil data revealed that the contamination of irrigation water and soil was caused by the discharge of industrial waste into the irrigation water. The heavy metal concentrations in leafy vegetables were mostly below the FAO permissible limits, whereas the As, Cr, and Pb concentrations in root vegetables exceeded the permissible limits. Correlation and cluster analyses of the vegetable data showed that the use of contaminated irrigation water and soil might be responsible for the heavy metal contamination in vegetables. According to the bioconcentration factor (BCF) in root vegetables, the transfer from soil to vegetables of As, Cr, Zn, and Pb was moderate/low, whereas that of Cd and Cu was high. Since these root vegetables were deemed unsafe for human consumption, this type of contamination should be considered more seriously when planting root vegetables.

Health risk of heavy metals from vegetables irrigated with sewage water in peri-urban of Dera Ismail Khan, Pakistan

Health risks of heavy metals in vegetables irrigated with sewage water were investigated in the present study. The findings indicated a massive accumulation of heavy metals in soil and vegetables collected from Dera Ismail khan, Pakistan. The concentration levels of heavy metal in vegetables grown on soil irrigated with untreated sewage water were significantly higher at (P ≤ 0.001) than in vegetables grown on fresh-water-irrigated soil and proceeded the recommended limits of World health organization. Moreover, the findings also indicated that the adults and children consuming such vegetables ingested a large proportion of the selected toxic metals. Health risk index was greater than one for Pb and Cd in all the selected vegetables and was greater than one for Ni in three vegetables like Spinacia oleracea, Benincasa fistulosa and Lactuca sativa. Health risk assessment would be a useful tool for information regarding any threats of heavy metals contamination in vegetables.

Evaluation of trace metals in vegetables sampled from farm and market sites of Accra Metropolis, Ghana

This is the first reported study of long term monitoring of heavy metal contamination of vegetables from Ghana. This study monitored heavy metals namely Arsenic (As), Cadmium (Cd), Cobalt (Co), Chromium (Cr), Copper (Cu), Iron (Fe), Manganese (Mn), Nickel (Ni), Lead (Pb) and Zinc (Zn) in consumable vegetables during 2013–2014. A total of 479 vegetables including cabbage (Brassica oleracea), carrot (Daucus carota), cucumber (Cucumis sativus), green pepper (Capsicum annuum) and lettuce (Lactuca sativa) were purchased from both farm and market sites within Accra Metropolis, Ghana. Samples were subjected to acid digestion and then analysed with Atomic Absorption Spectrometer (AAS). All the vegetables studied contained at least two or more metals; 18.99% of the samples had metal detections below the European Union (EU) guideline values, whereas 81% were above the limits. Vegetables from Mallam Attah market and the Ghana Broadcasting Corporation (GBC) sites registered the highest percentage exceedances (100%) with the largest value occurring in lettuce (97.41%). The data from Principal Component Analysis (PCA) revealed higher metal contaminations in leafy and fleshy vegetables than root vegetables. The results demonstrate the need for continuous monitoring of heavy metals in vegetables at various farm and market sites in Accra Metropolis, Ghana.