Transfer of metals from soil to vegetables in an area near a smelter in Nanning, China

Evaluation of the metal concentrations of wild mushroom species with their health risk assessments

The ability of mushrooms to accumulate heavy metals has increased concerns over their toxic effects on human health in recent years. The aim of this study was to determine the metal contents (Zn, Fe, Co, Mn, Cu, Pb, Ni, and Cd), daily intake of metal (DIM) and health risk index (HRI) values of nineteen different mushroom species (edible, inedible, and poisonous) collected from Uzungol, Trabzon (Turkey). Although the area where mushrooms were collected has the status of "Natural Park," there has been an excessive human settlement in recent years. Elemental analyses have shown that Fe, Mn, Cu, Zn, Co, Cd, Pb, and Ni concentrations in mushrooms were in the following ranges: 49.0-1713.0, 3.0-425.0, 3.0-154.0, 16.0-134.0, 0.17-1.79, 0.28-7.88, 0.07-5.68, and 0.24-6.82 mg/kg dry weight, respectively. As a result of DIM analysis, while it was determined that the daily consumption of Hygrophorus pudorinus, Meripilus giganteus, and Sarcodon imbricatus was safe for all the metals examined, HRI analysis showed that only M. giganteus and S. imbricatus can be consumed safely. The content of Cd was found to be above the legal limits determined by the competent authorities. According to Pearson correlation analysis, the correlations between Fe-Pb, Cu-Zn, Cd-Co, Pb-Co, Cd-Fe, Co-Fe, Cd-Pb, and Fe-Mn pairs were statistically significant (p < 0.01). Although the data obtained from this study did not provide clear data on environmental pollution in the area where the samples were collected, it was concluded that the competent authorities should take measures regarding possible environmental pollution at this location.

Transfer of heavy metals in fruits and vegetables grown in greenhouse cultivation systems and their health risks in Northwest China

Due to the high cropping index and substantial agricultural inputs in greenhouse cultivation systems (GCS) compared to traditional farming methods, the environmental problems caused by heavy metals in GCS are becoming increasingly serious. The concentration of the heavy metals As, Cd, Cr, Cu, Pb and Zn in soil and food crops were analyzed and assessed in two study areas. There were greater accumulation of heavy metals in soils from Central Shaanxi (CS) than that from Northern Shaanxi (NS). However, heavy metal concentrations in leafy vegetables were higher in NS compared to CS, particularly Cr accumulation in leafy vegetables. Overall, leafy vegetables contained higher concentrations of heavy metals than fresh fruits and fruit vegetables from both areas. The heavy metal transfer factors (TF) for fresh fruits and fruit vegetables were as follows: Cu > Zn > Cd > Cr > As > Pb. However, in leafy vegetables, Cd had a higher TF value than the other metals tested. The target hazard quotient (THQ) values were less than 1 for fruits and vegetables, except for As in leafy vegetables from NS. The THQ values indicated that As contamination was the most serious concern, followed by Cu > Zn > Cd > Pb > Cr in both areas. The soil threshold value (STV) based on THQ showed that the level of As in leafy vegetables grown in alkaline soil was 10.85, which was inferior to the current standards. This study demonstrates the health risks associated with the heavy metal content of fruits and vegetables grown in GCS and suggests that necessary measures should be taken to reduce the accumulation of heavy metals in GCS crops in northwest China.

Metal concentration and health risk assessment of eight Russula mushrooms collected from Kizilcahamam-Ankara, Turkey

The aim of this study was to determine the essential element (Zn, Ca, K, Fe, Na, and Mg), essential trace element (Co, Mn, Cr, and Cu), and non-essential element (Pb, Ni, and Cd) contents of eight different Russula species (R. risigallina (Batsch) Sacc., R. cyanoxantha (Schaeff.) Fr., R. delica Fr., R. vinosa Lindblad, R. olivacea (Schaeff.) Fr., R. velenovskyi Melzer & Zvára, R. turci Bres., and R. parazurea Jul. Schäff.) collected from Soguksu National Park (Turkey), which is a region away from the city center (Kizilcahamam, Ankara). In addition to the metal contents of these species, daily intake and health risk index values of the metals in question were also calculated and discussed. As a result of elemental analysis, the major elements were K (28980-58,380 mg/kg), Mg (704-1404 mg/kg), and Ca (190-1662 mg/kg). Except for R. risigallina, R. olivacea, and R. velenovskyi, elemental concentrations were within the limits that can be safely consumed as nutrients in terms of their metal content. The daily intakes of metal (DIM) values of R. risigallina and R. olivacea for Cr exceed the reference dose limits (3.80 and 3.87 μg/kg body weight/serving, respectively). According to the health risk index (HRI) measurements, the HRI values of R. risigallina and R. olivacea for Cr and of R. velenovskyi for Cd were found to be above 1.0 and could pose a health risk. In order to analyze the mineral composition variability of the studied mushroom species, principal component analysis (PCA) and the hierarchical cluster analysis (HCA) techniques were also performed. Regarding the significant correlations between all descriptors (r > 0.7), there was a positive relationship between Mg-K, Ni-Co, Ni-Na, Cr-Ni, Cr-Co, Zn-Mg, Zn-K, Cd-Mg couples.

Potentially toxic elements pollution in road deposited sediments around the active smelting industry of Korea

Potentially toxic elements (PTEs) were investigated in the different sizes of road deposited sediments (RDS) around the active smelting industry to understand their sources and to assess the pollution and ecological risk levels. The highest PTEs concentrations was shown near the raw materials import port and the smelting facilities. The fine particles of RDS showed extremely high PTEs concentrations. Zn has the highest mean concentration in the < 63 μm particle size of RDS, followed by Pb > Cu > As > Cr > Ni > Cd > Hg. The PTEs concentrations of this study were the highest values compared to the soils around the smelter and the RDS in urban and industrial areas in the world. This indicates that these PTEs pollution in RDS were mainly attributed to the transportation of raw materials for the smelting industry. According to nemerow pollution index calculation, RDS at all sampling sites with particles of less than 250 mm was seriously polluted with PTEs. The ecological risk was also found to be very high in all RDS fractions and highly toxic elements such as Cd, Pb and Hg pose extremely risk. Given the total amounts PTEs in the road surface, it is necessary to apply RDS removal management plan to reduce the PTEs pollution.

Chromium accumulation in soil, water and forage samples in automobile emission area

Environmental contamination caused by various pollutants due to automobile emissions is an alarming issue. One important type of the pollutants are heavy metals, including chromium (Cr) added by the exhaust of toxic smoke of vehicles. These pollutants are added to forage crops cultivated near roadsides, soil and irrigation water. However, rare studies have been conducted to infer Cr accumulation near heavy automobile emission areas. This study was conducted to determine Cr concentration in irrigation water, soil and forage. Water, forage and soil samples were collected from area impacted by heavy traffic. Atomic absorption spectrophotometer was used to appraise Cr values in the collected samples. Chromium values ranged from 0.50 to 1.14 mg/kg in water samples and from 0.04 to 2.23 mg/kg in soil samples. It was highest in Zea mays grown soil, whereas minimum in Brassica campestris soil. The Cr values in forages ranged from 0.09 to 1.06 mg/kg. Z. mays observed the highest Cr accumulation, whereas the lowest Cr accrual was noted for B. campestris. The pollution load index (PLI) was the highest for Trifolium alexandrinum, while the lowest for Z. mays. Bio-concentration factor (BCF) ranged from 0.14 to 8.63. The highest BCF was noted for T. alexandrinum, while the lowest for Z. mays. The highest and the lowest daily intake of metal (DIM) was noted for Z. mays at different sites. Health risk index (HRI) was highest for Z. mays and lowest for B. campestris. The results add valuable information on heavy metal accumulation in water, soil and forage samples near to automobile emission area.

Trace metal accumulation in pepper (Capsicum annuum L.) grown using organic fertilizers and health risk assessment from consumption

Organic farming and healthy nutrition are among the most popular topics of recent times. However, organic fertilizers, which are one of the important elements of organic agriculture, have the potential to threaten human health with the toxic substances they may contain. The present study aimed to observe the effect of farmyard manure, poultry waste and press mud on metal accumulation in pepper (Capsicum annuum L.) to determine the pollution severity of soil and to examine the health risk due to the consumption of organic fertilizer applied pepper. The multipurpose pot experiment was conducted to study the agronomical growth performance and accretion of metals in C. annuum grown with different organic fertilizers in the soil at the area of the Department of Botany, University of Sargodha, Pakistan. The trace metal contents in soil and C. annuum samples were analysed by atomic absorption spectrophotometer (AA-6300 Shimadzu Japan). Trace metal concentrations in soil samples ranged from 0.152 to 0.850, 2.167 to 5.812, 0.345 to 1.235, 2.682 to 5.875, 0.095 to 0.558, 6.132 to 17.062, 0.172 to 2.235 and 6.670 to 22.585 mg/kg for Cd, Co, Cr, Cu, Pb, Fe, Mn and Zn, respectively. In pepper samples, trace metal concentrations ranged from 0.364 to 2.206, 0.305 to 4.042, 0.272 to 1.160, 1.132 to 1.305, 0.164 to 0.204, 4.736 to 17.000, 0.844 to 1.150 and 14.751 to 18.385 mg/kg for Cd, Co, Cr, Cu, Pb, Fe, Mn and Zn, respectively. The accumulation of Cd and Pb had higher values of HRI than 1 and these values suggested that these metals had probability to cause health problems.

Effects of organic and chemical fertilizers on the growth, heavy metal/metalloid accumulation, and human health risk of wheat (Triticum aestivum L.)

The aim of this study was to determine and compare the effect of the chemical fertilizer and organic fertilizers such as cow manure and poultry manure applications on the heavy metal/metalloid accumulation in the wheat samples. A field experiment was conducted using a complete randomized block design with three replicates per treatment to observe the impact of organic and chemical fertilizers on the heavy metal/metalloid accumulation in a wheat variety (Lasani-08). Heavy metal/metalloid concentrations in the root, shoot, and grains of wheat samples were determined using an atomic absorption spectrophotometer (AAS). In addition, the growth parameters of wheat samples were assigned. Results indicated that morphological parameters showed maximum growth under chemical fertilizer treatment. The heavy metal/metalloid concentrations in the wheat grains ranged from 12.95 to 25.83, 1.03 to 1.11, 16.83 to 20.26, 0.92 to 0.98, 0.504 to 1.997, 2.24 to 5.98, and 0.493 to 1.154 mg/kg for Zn, Co, Fe, Cd, Pb, Cu, and Cr, respectively. All heavy metal/metalloid values in the present study were within the safe limits reported by the FAO/WHO except for Pb. However, the health risk index determined for all metals are higher in the wheat grown with chemical fertilizer applications, but it has been shown that the consumption of wheat grown with organic and chemical applications is not hazardous for health.

Evaluating heavy metals contamination in soil and vegetables in the region of North India: Levels, transfer and potential human health risk analysis

This study determined the heavy metals (HMs) accumulation in different vegetables in different seasons and attributed a serious health hazard to human adults due to the consumption of such vegetables in Jhansi. The total amounts of zinc (Zn), lead (Pb), nickel (Ni), manganese (Mn), copper (Cu), cobalt (Co), and cadmium (Cd) were analysed in 28 composite samples of soil and vegetables (Fenugreek, spinach, eggplant, and chilli) collected from seven agricultural fields. The transfer factor (TF) of HMs from soil to analysed vegetables was calculated, and significant non-carcinogenic health risks due to exposure to analysed heavy metals via consumption of these vegetables were computed. The statistical analysis involving Principal Component Analysis (PCA) and Pearson's correlation matrix suggested that anthropogenic activities were a major source of HMs in the study areas. The target hazard quotient of Cd, Mn, and Pb for fenugreek (2.156, 2.143, and 2.228, respectively) and spinach (3.697, 3.509, 5.539, respectively) exceeded the unity, indicating the high possibilities of non-carcinogenic health risks if regularly consumed by human beings. This study strongly suggests the continuous monitoring of soil, irrigation water, and vegetables to prohibit excessive accumulation in the food chain.

Bioaccumulation of cadmium in different genotypes of wheat crops irrigated with different sources of water in agricultural regions

The study was carried out to evaluate the health risks associated with accumulation of cadmium in the different genotypes of wheat, grown in agricultural regions of Punjab, Pakistan. Five genotypes irrigated with three varied water sources were selected randomly from each region. Among all sources of water, types of soil, and grain samples, the cadmium (Cd) quantities were found (2.24-2.82 mg/L, 1.75-4.16 mg/kg, 0.86-1.90, respectively), exceeding the maximum permissible limits (0.01 mg/L, 1.1 mg/kg, 0.2 mg/kg, respectively) described by FAO/WHO. The pollution load index (PLI) exhibited by all of the samples was higher than 1.00, the permissible limit; however, other factors including bioaccumulation, translocation, bio-concentration, daily intake, and enrichment values of Cd were less than 1.00. Moreover, the health risk index for cadmium in all types of wheat grain samples was less than 1.00. The study concluded that the continuous use of wastewater resources may lead to the accumulation of cadmium in the vital body organs that may cause severe health hazards.

Contamination characteristics, source analysis, and ecological risk assessment of toxic metals and metalloid in agricultural soil in Yuzhong, China

Human activities have caused toxic metal pollution and ecological risks to agricultural soil. In this study, 291 topsoil samples, collected in the agricultural soil system of Yuzhong, China, were selected to study the toxic metals and metalloids contamination characteristics, source and ecological risk based on geostatistics, pollution index, and ecological risk index. The main distribution of As is adjacent to pasture land and mainly comes from animal husbandry; Pb was observed near a coal mining factory and the Yellow River and was derived from industry and transportation; Cd was similar to Pb and was mainly derived from industry, transportation, and agriculture; Cr was found near a cement plant and was derived from industry and transportation; and Hg was found near an urban area and was mainly from industry and domestic garbage. The ratio of these elements exceeding the soil background value reached 99.9%. Except for the excess amounts of Cd and Hg in some samples, Cr, Hg, and As were mostly below permissible limits. Moreover, the comprehensive potential ecological risk of toxic metals is mainly at medium level and below, whereas the risks of Cd and Hg are higher. Control of Cd and Hg is important to prevent soil pollution. This study explains the current contamination situation, the predominant contaminants and their sources, and provides emphasis and direction for agricultural soil remediation.

Indium Uptake and Accumulation by Rice and Wheat and Health Risk Associated with Their Consumption

The increasing use of indium in high-tech industries has inevitably caused its release into the environment. However, knowledge of its environmental fate has been very limited so far. This study investigates the indium uptake and accumulation by two staple crops, rice (Oryza sativa L.) and wheat (Triticum aestivum L.), and evaluates potential risks associated with their consumption. Rice and wheat were grown on three kinds of soil, including acidic soils spiked with a high indium concentration (1.0 mmol kg^-1), which is considered the worst-case scenario, because high soil acidity promotes indium bioavailability. The results revealed that a large portion of soil indium was associated with iron hydroxides, even in acidic soils. Indium precipitates in soils resulted in relatively low availability at the plant root site. Most absorbed indium accumulated at the roots, with only a tiny portion reaching the grains. The corresponding Hazard Quotient indicated no adverse effects on human health. Due to the low translocation of indium from soil to grain, the consumption of rice and wheat grains harvested from indium-contaminated soils may pose an insignificant risk to human health. Further field studies are necessary to better elucidate the risks associated with consuming crops grown in indium-contaminated soils.

Current status, spatial features, health risks, and potential driving factors of soil heavy metal pollution in China at province level

In this study we systematically reviewed 1203 research papers published between 2008 and 2018 in China and recorded related data on eight kinds of soil heavy metals (Cr, Pb, Cd, Hg, As, Cu, Zn, and Ni). Based on that, the pollution levels, ecological risk and health risk caused by soil heavy metals were evaluated and the pollution hot spots and potential driving factors of different heavy metals in different provinces were also identified. Results indicated accumulation of heavy metals in soils of most provinces in China compared with background values. Consistent with previous findings, the most prevalent polluted heavy metals were Cd and Hg. Polluted regions are mainly located in central, southern and southwestern China. Hunan, Guangxi, Yunnan, and Guangdong provinces were the most polluted provinces. For the potential health risk caused by heavy metals pollution, children are more likely confront with non-carcinogenic risk than adults and seniors. And children in Hunan and Guangxi province were experiencing relatively larger non-carcinogenic risk. In addition, children in part of provinces were undergoing potentially carcinogenic risks due to soil heavy metals exposure. Furthermore, in our study the 31 provinces in mainland China were divided into six subsets according to corresponding potential driving factors for heavy metal accumulation. Our study provide more comprehensive and updated information for contributing to better soil management, soil remediation, and soil contamination control in China.

Novel insights into effects of silicon-rich biochar (Sichar) amendment on cadmium uptake, translocation and accumulation in rice plants

The effects and mechanisms of biochars with different silicon (Si) contents on Cadmium (Cd) uptake, translocation and accumulation in rice plants are not fully understood. Herein, we report a pot study to disentangle the interaction mechanisms of Si-rich biochars (Sichar RH300, RH700) and Si-deficient biochars (WB300, WB700) with high-Si soil (HSS) and low-Si soil (LSS) on Cadmium (Cd) and Si accumulation in rice (including grains, straw, and roots). Sichar was found to be better than Si-deficient biochars in reducing Cd uptake and accumulation in rice, and RH300 amendment was better than the RH700 treatment. The surface complexation of Cd with carboxyl groups and Si from biochar led Cd immobilization in soil, as portrayed by Fourier transformed infrared spectroscopy and X-ray photoelectron spectroscopy. The high Si content of biochars indicates a relatively lower bioaccumulation factor and translocation factor of Cd. The Sichar (e.g., RH300) treatment significantly increases the silicon concentration in rice (including grains, straw, and roots), but the Si concentrations of rice grains and roots decrease with WB700-amended LSS. Negative correlations between the concentrations of rice Si and Cd were observed, which could be related to lower expression as observed by Si transport genes (Lsi1 and Lsi3) in rice by Sichar amendment. These findings suggest that the Si released from Sichars can reduce the gene expression of Si transport channel of rice roots and inhibit the transport channel of Si, thus thereby inhibiting the Cd uptake, probably due to the utilization of same channel for Cd and Si. Integrative mechanisms of Sichar (RH300 and RH700) reduced Cd plant accumulation can be proposed by soil immobilization, inhibition of root transport, and prevention of plant translocation.

Metal concentration and health risk assessment of fifteen wild mushrooms collected from the Ankara University Campus (Turkey)

The aim of this study is to analyze Fe, Mn, Cu, Zn, Co, Cd, Pb, and Ni contents of Cyclocybe cylindracea, Armillaria mellea, Bjerkandera adusta, Rheubarbariboletus armeniacus, Coprinellus disseminatus, C. micaceus, C. comatus, Inonotus hispidus, Lepista nuda, Leucoagaricus leucothites, Pleurotus ostreatus, Cerioporus squamosus, Schizophyllum commune, Scleroderma verrucosum, and Trametes trogii collected from the Ankara University Besevler 10th Year Campus (Turkey), an area where human settlement and traffic are intense. In addition to the elemental analysis, the daily intake of metal (DIM) and health risk index (HRI) values of the edible ones were also calculated. Fe, Mn, Cu, Zn, Co, Cd, Pb, and Ni concentrations of the samples were found to be 112.0-5079.0, 3.0-124.0, 4.0-77.0, 2.0-196.0, 0.18-2.98, 0.18-5.3, 0.04-10.98, and 0.22-8.23 mg/kg dry weight, respectively. As a result of DIM and HRI analysis, C. cylindracea, L. nuda, and C. squamosus were found to be within the reference dose limits determined by competent authorities and can be safely consumed in terms of all metals studied. However, the Cd, Co, and Fe contents of C. micaceus were found to be above 1.0 (1.06, 4.25, and 7.06, respectively). In addition, it has been found that A. mellea, R. armeniacus, C. comatus, L. leucothites, and P. ostreatus are toxic in terms of Cd/Co, Fe/Pb, Co/Fe, Cd, and Fe contents, respectively. As the area in question is a traffic intensive area, it has been concluded that the emissions of the vehicles should be controlled in terms of legal limits and that the consumption of some mushrooms in this region should not be preferred until necessary measures are taken.

Translocation of potential toxic elements from soil to black cabbage (Brassica oleracea L.) growing in an abandoned mining district area of the Apuan Alps (Tuscany, Italy)

In the Apuan Alps (Tuscany, Italy), long-lasting mining activities have favored the mobilization of numerous metals present in sulfosalts originated from low-grade metamorphism mineralization. Such materials, rich in potentially toxic elements such as antimony, arsenic, barium, copper, lead, thallium, tin and zinc, represent the substrate on which soils of different thicknesses have been formed and is currently used for agricultural activities. High concern is particularly arising about the food safety due to traditional horticultural practices, since it is very common in this area to cultivate vegetables in private gardens for both self-consuming and/or local market. In this context, a monitoring survey on both soils and vegetables was performed over the area, with particular attention to Brassica oleracea L. as traditional food crop, to assess the degree of contamination of the area, the possible translocation to vegetables and the potential human risk linked to vegetable ingestion. This analysis reveals a different degree of soil contamination in the area and a general high human risk linked to cabbage cultivation and ingestion in the whole area.

Bioaccumulation of lead in different varieties of wheat plant irrigated with wastewater in remote agricultural regions

The accumulation of heavy metals by crops irrigated with wastewater has been considered as a serious environmental problem in many developing countries, where the wastewater irrigation has emerged as a common practice. In this research, we were concerned with the highly toxic metal lead (Pb) in water, agricultural soils, and wheat crops, and the possible risk on human health in the peripheral agricultural regions of Punjab, Pakistan. Various types of irrigated water (ground, sewage, industrial), soil, and wheat plant (root, shoot, grain) samples of five different varieties (Seher-2006, Punjab-2011, Faislabad-2008, Watan, and Galaxy-2013) were collected from seven different districts and then pooled up to make one composite sample and analyzed for Cd concentration. The various pollution and mobility indices (pollution load index, enrichment factor, daily intake of metal, health risk index, translocation factor, bioaccumulation factor, and bio-concentration factor) were also calculated. The descending order for Pb concentration was as follows: water>soil>wheat plant. The range of concentration of Pb in all types of water, soil, and wheat plant (root, shoot, grains) samples was (7.05-7.83 mg/l), (6.32-7.74 mg/kg), (3.23-4.82, 1.14-2.75, 0.09-0.51 mg/kg), respectively. The concentration of Pb in all types of water samples exceeded the maximum permissible limit. There were values found to be < 1.00 in all the pollution and mobility indices for all types of samples. These results reveal that high levels of Pb in irrigated water may pollute the soil and wheat plants of these regions in the near future, if various control measures have not been taken. It may pose a great health risk to the local human and animal populations. Preventive measures should be taken to reduce heavy metal pollution of irrigation water and soils to protect both human and animal health in various regions of Punjab, Pakistan.

Human Risk from Exposure to Heavy Metals and Arsenic in Water from Rivers with Mining Influence in the Central Andes of Peru

Water pollution by heavy metals is one of the leading environmental concerns as a result of intense anthropogenic pressure on the aquatic environment. This constitutes a significant limitation to the human right of access to drinking water. In this context, the risk to humans from exposure to heavy metals and arsenic in water from rivers subject to mining influence in the Central Andes of Peru was assessed. Water samples were collected from seven rivers at 63 sampling sites, and concentrations of Cu, Fe, Pb, Zn, and As were determined using flame atomic absorption spectrophotometry. Cluster analysis was used to group 21 sampling sites into four groups with similar chemical characteristics, and principal component analysis was used to simplify the complex relationship between the toxic elements by generating two main components with a total percentage of variation of 86%. Fe, Zn, and As had higher percentages of contribution in the Mantaro, Cunas, and Chia rivers. The hazard quotient was highest for children and adults. The hazard index for ingestion of all the studied heavy metals and As was higher than the threshold value (HIing > 1). HIing in 43% of the rivers indicated that the adult population is at risk of non-carcinogenic effects, and HIing in 14% of the rivers revealed a very high health risk. The risk of cancer by ingestion for children varied from medium to high risk and for adults from low to high risk.

A study on the transfer of chromium from meadows to grazing livestock: an assessment of health risk

The present investigation was performed in different district of Punjab to determine the chromium level in soil, forages, and blood plasma of the small ruminants (goat and sheep). The results showed that the mean concentrations of chromium in the soil of Sargodha, Mianwali, and Bhakkar districts were ranged from 1.8 to 2.3, 3.01 to 4.99, and 2.04 to 2.87 mg/kg, respectively. The chromium level was higher in Mianwali compared with Sargodha and Bhakkar. The mean concentrations of chromium in forages which were used for feeding purposes were found between 0.672 and 1.631, 1.493 and 2.612, and 0.7804 and 1.047 mg/kg for Sargodha, Mianwali, and Bhakkar, respectively. The mean concentrations of chromium in blood plasma of goat which consumed the contaminated forages were between 0.666 and 1.269 mg/L in Sargodha, 0.657 and 0.752 mg/L in Mianwali, and 1.39 and 2.37 mg/L in Bhakkar. In blood plasma of sheep, the residual levels of chromium in the districts Sargodha, Mianwali, and Bhakkar were ranged from 0.673 to 1.384, 0.83 to 1.086, and 1.496 to 3.611 mg/L, respectively. In the present research, there was a higher concentration of chromium in blood plasma of sheep from Bhakkar and the lowest was in Sargodha. The chromium level in blood samples was found to be higher than the tolerable level of 1.0 mg/L in all districts. In light of these results, it was concluded that chromium levels in the soil and forages of all sites were present within the safe limit while in blood samples of sheep and goats were found to be above the acceptable limit. Sheep and goats also consume water from river, streams, and ponds and other contaminated water sources. So it might be the reason of higher level of chromium in their blood plasma. Hence, the proper monitoring of study sites will be necessary to prevent the excessive accumulation of chromium in ruminants in the near future.

Level and speciation of nickel in some forages in relation to spatial and temporal fluctuations

The present experimental work was conducted at different sites of district Bhakkar, a semiarid region of Pakistan, to assess whether the goats are suffering nickel deficiency or toxicity and what are the possible seasonal effects on the availability and translocation of nickel in food chain. A total of 27 forage and 320 goats according to four physiological stages [does (she goat), bucks (he goat), wether (castrated), juvenile (6 month)] were recruited for this study. To fulfill this objective, soil, forage, blood plasma, urine, and feces samples were collected in 4 seasons of the year at 2 sites and were analyzed by atomic absorption spectrophotometer for nickel concentration. Different indices BCF, EF, and PLI were also studied to check the metal transfer. The results showed that sites had significant (P < 0.05) effect on nickel concentration in soil, forage, and goats. On the other hand, season and site x season had nonsignificant (P > 0.05) effects on nickel level in soil and goats. The soil (0.68-0.71 mg kg^-1), forage (3.41-3.70 mg/kg), and blood (0.21-0.28 mg/l) level was lower than the permissible limits, while feces (0.57-1.34 mg/kg) and urine (0.35-1.32 mg/l) had enough concentration of nickel. Sources showed significant (P < 0.05) effects on Ni level in all stages of goats. All stages of goats except Wether (castrated) showed low level of nickel in blood. Most fluctuations in nickel concentration were observed in (S1) summer (low) and spring (S4) (high) season as a whole, while overall site 2 had high level of nickel than site 1. Thus, nickel showed deficiency in soil, forage, as well as in all stages of goats except wether goats. Nickel containing mineral mixtures are essential for does (she goat), bucks (he goat), and juveniles (6 months old), so application of Ni containing fertilizers to the soil and forage of that region and supplementation of Ni mineral mixture for grazing ruminants should be done.

Metal concentration and health risk assessment of wild mushrooms collected from the Black Sea region of Turkey

Mushrooms are rich sources of organic nutrients (especially proteins). However, they can excessively accumulate metals in their fruiting bodies that pose a risk to human health. The aim of this study was the determination of Cd, Co, Cu, Fe, Mn, Ni, Pb, and Zn contents, daily intake, and health risk index values of some mushroom species collected from the eastern Black Sea region of Turkey (Arsin, Trabzon). The samples were collected from hazelnut gardens that are free from industrial pollution and have a low population density. As a result of elemental analysis, it was determined that the concentration ranges of Cd, Co, Cu, Fe, Mn, Ni, Pb, and Zn in the mushrooms were as follows: 0.29-9.11, 0.04-3.70, 0.01-8.29, 0.18-20.82, 3.1-79.8, 5.2-673.0, 14.9-752.0, 63.0-7769.0 mg/kg dry weight. Daily intakes of all the elements were found to be below the reference dose in Fistulina hepatica, Hydnum repandum, Macrolepiota procera, and Tapinella atrotomentosa. Amanita caesarea, Agrocybe praecox, Amanita vaginata, Cantharellus cibarius, Craterellus cornucopioides, Daedalea quercina, Gymnopus dryophilus, Ganoderma lucidum, and Infundibulicybe gibba were found to have high risk index values especially with respect to Cd, Co, and Pb. According to Pearson correlation analysis, the correlations between Fe-Mn (0.840, p < 0.01) and Pb-Ni (0.7540, p < 0.01) couples are significant.

Bioaccumulation and health risk assessment of heavy metals in Musa paradisiaca, Zea mays, Cucumeropsis manii and Manihot esculenta cultivated in Onne, Rivers State, Nigeria

This study was carried out to investigate heavy metals concentrations: lead (Pb), cobalt (Co), cadmium (Cd), zinc (Zn), nickel (Ni), copper (Cu) and manganese (Mn) in Musa paradisiaca (plantain), Zea mays (maize), Cucumeropsis manii (melon), Manihot esculenta (cassava) and soil samples from dumpsites in Onne, Eleme Local Government Area, Rivers State, Nigeria. The plant leaf and soil samples were measured for heavy metals concentrations using atomic absorption spectrophotometer. The health risk index (HRI) of the heavy metals following the consumption of these plant materials by the populace was estimated using standard protocols. The heavy metals concentrations in the leaf samples ranged from 0.012-14.712 mg/kg, whereas those of the soil samples were within the range of 2.543-16.459 mg/kg. Cd concentrations in the soil and leaf samples were above the maximum permissible level according to the World Health Organization (WHO). The bioaccumulation of the heavy metals followed the trend: (M. paradisiaca) Zn > Pb > Co > Mn > Cu > Cd > Ni; (Z. mays) Mn > Pb > Co > Zn > Cu > Cd > Ni; (C. mannii) Mn > Co > Pb > Cu > Zn > Cd > Ni; (M. esculenta) Zn > Pb > Mn > Cu > Co > Ni > Cd. The highest bioaccumulation of the heavy metals occurred in M. esculenta. The estimated HRI of Pb in M. esculenta was greater than 1. HRI > 1 was indicative that the consumer population is not safe. Cassava-based meals from the dumpsites contained Pb at toxic level, whereas Co, Cd, Zn, Ni, Cu, and Mn concentrations in plantain-, maize- and melon-based meals were relatively within safe limits.

Relationship of Arsenic and Lead in Soil with Fruit and Leaves of Apple Trees at Selected Orchards in Michigan

ABSTRACT

Historically, lead arsenate pesticides were commonly used in fruit orchards. Residues of metals from this historical use can persist in soil for decades, which can result in potential risk for humans if they consume fruits grown on contaminated soil. This research was conducted to assess lead and arsenic levels in apples, leaves, and orchard soil where the apples were grown to determine the relationship between metal levels in fruits and fruit products with those in orchard soil. Soil and tree tissue samples were collected from several Michigan farms, and metal concentrations were quantified by using microwave extraction and inductively coupled plasma mass spectrometry. Soil samples were collected at depths of 0 to 20 cm and 20 to 40 cm at a distance of 1 m from the tree trunk. Fruit samples also were processed into juice and pomace fractions to assess the partitioning of arsenic and lead during juice processing. The lead concentration was significantly higher in topsoil (9.4 μg/kg) compared with subsoil (6.9 μg/kg), but the arsenic content did not differ between the two soil layers (P > 0.05). Lead concentrations in apple leaves were correlated with lead in topsoil (0 to 20 cm; P = 0.03). Concentrations of total arsenic in all juice samples were less than 1 μg/kg and showed less potential than lead for uptake and translocation to fruits. There was no significant relationship between soil arsenic content and total arsenic concentrations in juice, pomace, and leaf samples (P > 0.05). Results of this research indicate that lead and total arsenic concentrations in apples and apple products from these selected orchards in Michigan are unlikely to be impacted by the contamination of these metals in orchard soil.

HIGHLIGHTS

Trace Elements in Soils and Vegetables from Market Gardens of Urban Areas in Marrakech City

The consumption of vegetables grown on soils polluted by trace elements can cause a serious threat for animal and human health and disturb the functioning of the ecosystem. The aim of this work is to determine the concentrations of As, Cd, Co, Cr, Cu, Ni, Pb, Mn, and Zn in soils and different vegetables from market gardens of urban areas in Marrakech city in order to investigate human health risk through ingestion of contaminated vegetables. Plant transfer factor (TF), daily intake of metals (DIM), and health risk index (HRI) were calculated. The concentrations of all metals studied in the garden top soils were within the threshold values. The Cu, Zn, Co, Mn, and As concentration in the edible parts of vegetables were within the safe limits. However, Cd and Pb in Malva parviflora and Cd in Brassica rapa, and Cr and Ni in Coriandrum sativum exceeded their permissible limits. The TF for these nine metals varied between 0.01 and 1.35. The classification of TEs according to their TF is as follows: Cu > Zn > Cd > Ni > Cr > Pb > Mn > Co > As. The maximum value was recorded in Coriandrum sativum while the minimum value was recorded in Cynara cardunculus. The HRI values were within the safe limit (< one) except for Pb in Malva parviflora. This can lead to risks to the health of the human population, especially children, consuming contaminated plants. Thus, the monitoring and prevention of health risks related to the consumption of plants grown in (peri)urban areas are necessary and essential to propose recommendations to both gardeners and decision-makers.

Effect of biochars on bioaccumulation and human health risks of potentially toxic elements in wheat (Triticum aestivum L.) cultivated on industrially contaminated soil

In the present study, biochars (BCs) derived from naturally grown green waste (Cynodon dactylon L.) were investigated regarding their impacts on bioaccumulation of potentially toxic elements (PTEs), agronomic properties and human health risks of wheat crop cultivated on long-term industrially contaminated soil. Typically, three types of BCs were pyrolyzed at different highest temperature of treatment (HTT), i.e. 400 °C, 600 °C and 800 °C, in a horizontal reactor and applied to the contaminated soil with 2% and 5% (w/w) ratio. The characterization results of the BCs showed that significant positive changes in fundamental characteristics such as porosity, surface area, cation exchange capacity, dissolved organic carbon, phosphorus and potassium have occurred with increased HTT. The analytical results of wheat crop indicated that the BCs applications significantly (p ≤ 0.05) reduced concentration of PTEs in roots (48-95%), shoots (38-91%), leaves (30-91%) and grains (38-93%) of wheat plants. After the BCs application, the agronomic properties were enhanced up to 6-18%, 18-38%, 17-46%, 13-45%, 15-42%, 22-55% and 34-57% for germination rate, shoot length, shoot biomass, spike length, spike biomass, grain biomass and root biomass respectively. The human health risks of PTEs were significantly (p ≤ 0.05) decreased (31-93%) from toxicity level to safe level (except for Mn and Cu), after the BCs application. Based on the current study, the BCs (especially 800BC5) were recommended for reducing bioaccumulation of PTEs in different parts of the wheat plant, increasing growth and yield of wheat crop and decreasing human health risks via consumption of wheat grains.

A study on the seasonal transfer of two metals from pasture to animals: health risk assessment

Accretion of heavy metals in forage is a potential risk to grazing animals due to their uptake by plants and its entrance into the food chain. This study aimed to examine the Mn and Cd concentration from different samples. Sampling was done twice after the interval of 6 months during 2018; five different sites from Chakwal (Pidh, Tobar, Ratoccha, Kalar Kahar Road, Choa Saiden Shah and Chakwal Road, Choa Saiden Shah) were selected. Thirty samples of soil, forage (Acacia nilotica, Ziziphus nummularia, and Acacia modesta), and blood were collected. Forage and soil samples were dried, ground very fine, digested by wet digestion method, and analyzed by atomic absorption spectrophotometer. Samples collected from site I and site II had a very high concentration of heavy metals because these sites were very close to the coal mines and receive higher contamination. Manganese concentration in the soil fluctuated from 5.46 to 1.20, in the forage 6.84 to 1.00, and in the blood 5.21 to 1.03 mg/l, and cadmium concentration in the soil fluctuate from 1.85 to 0.03, in the forage 0.57 to 0.16, and in the blood 1.67 to 0.25 mg/l. Manganese concentration was higher as compared to the Cd. Higher concentration of Mn shows that this metal is due to human activities. Pollution load index value of Cd was higher than 1 in some samples, and the value fluctuates from 0.01 to 1.24 mg/kg. The values of a bioconcentration factor for Mn were greater than 1. Daily intake of metal value fluctuates from 0.01 to 1.03 mg/kg. Health risk index value ranges from 0.03 to 1.09 mg/kg. Health risk index of metals showed the risk which is due to the intake of contaminated fodder. From the soil, the metals can enter forage and bioaccumulate in the food chain. The health risk index was highest for Cd. The result obtained from the present research work indicated that there is a biomagnification of both metals in the food chain due to mining activities.

Health risks of heavy metal exposure and microbial contamination through consumption of vegetables irrigated with treated wastewater at Dubai, UAE

The shortage of fresh water is a major problem throughout the world, but the situation is worst in the arid and semiarid regions. Therefore, reuse of nonconventional water resources such as treated wastewater (TWW) is a common practice to irrigate field crops, vegetables, and forestry sectors. The present study was conducted to evaluate the significant impact of different heavy metals such as copper (Cu), iron (Fe), chromium (Cr), and zinc (Zn) on the soil and leafy, root, and fruit vegetables following irrigation with TWW through subsurface drip irrigation. Our results indicate that iron (Fe) was highest in lettuce followed by spinach, and Zn and Cr were second and third most abundant element in the different vegetables. Eggplant and radish showed the lowest concentrations of various heavy metals. A significant difference was observed in transfer factor (TF) among vegetables, and highest TF_soil-veg was observed for Fe in lettuce and the lowest for Cr in eggplant. Estimated daily intake (EDI) was the lowest in adults and highest in children. Target hazard quotient (THQ) of Cu, Zn, and Fe being < 1.0 appears relatively safe in all the tested vegetables. Risk index (RI) values showed that heavy metals were lower than 1.0 and hence lower risk for human. The combined HI values for Cu, Zn, Cd, Cr, and Pb were substaintionaly higher 12.8 and 9.21 after consumption of lettuce and carrot. So, consumption of these vegetables should be avoided after irrigation with TWW. Spinach exhibited maximum total coliform loading, while ecological risk was negligible due to sandy nature of soil type. Health risks to human could be reduced through proper selection of suitable vegetables, time of maturity, and consumed organs (leaf, fruit, or root part). Appropriate should be followed to decontaminate the microbial load in order to avoid any risks to human health (both adults and children).

Wild edible mushrooms from Mediterranean region: Metal concentrations and health risk assessment

Worldwide, among the forest products, wild edible mushrooms constitute an important part because they represent food source as well as income source for many local communities. Thirteen essential elements (Ca, Co, Cr, Cu, Fe, K, Mg, Mn and Zn) and non-essential elements (Al, Cd, Ni and Pb) in wild edible mushrooms from six families (Agaricaceae, Auriculariaceae, Hygrophoraceae, Russulaceae, Suillaceae, and Tricholomataceae) originated from the Mediterranean region of Turkey were determined. Major element was K, followed by Ca, Mg, Fe and Al. Concentrations of detected elements were in the range from 0.05 mg/kg (Co) to 141,400 mg/kg (K). Health Risk Index for elements that may pose health problems indicated that safe limits were exceeded for Cd (L. nuda, L. decastes, M. exscissa, R. albonigra, R. delica and T. terreum), Ni (A. auricula-judae and S. luteus) as well as for Fe (A. auricula-judae and M. paedida). In Arpacık village and Deliosman village areas the highest number of wild edible mushrooms with HRI>1 was collected. The differences and similarities between mushroom species were established by Principal Component Analysis and Hierarchical Component Analysis.

Geoassessment of heavy metals in rural and urban floodplain soils: health implications for consumers of Celosia argentea and Corchorus olitorius vegetables in Sagamu, Nigeria

Vegetable gardening in floodplains in western Nigeria has assumed economic significance but with attendant pressure on urban field in the dry season. This study assessed soil properties and bioconcentration of cadmium (Cd), iron (Fe) and lead (Pb), in edible parts of Celosia argentea and Corchorus olitorius grown in floodplains. Soil and vegetable samples were collected at 20 m intervals from rural (Atoyo and Ewuga) and urban (GRA Rd. and Lafarge) floodplain gardens in Sagamu. Six samples were collected per location making a total of 24 samples each of soil and vegetable. Samples were analyzed for soil properties and heavy metal concentration in the vegetables. Transfer factor (TF), contamination factor (CF), daily intake of metals (DIM), health risk index (HRI) and geoaccumulation index (I_geo) were also determined. Soil properties varied significantly, with the highest soil concentration of Cd (0.91 mg kg^-1) and Fe (208.20 mg kg^-1) recorded at Lafarge. The highest soil Pb (223.77 mg kg^-1) was at Atoyo. Bioaccumulation of Fe was significantly (p ≤ 0.05) higher in C. argentea than C. olitorius. Heavy metal bioaccumulation beyond allowable limits was recorded for Cd (0.46 mg kg^-1) and Pb (49.30 mg kg^-1) by C. argentea and C. olitorius, respectively. Soil contamination was dominated by Cd at Lafarge and by Pb at Atoyo. The DIM and HRI indices indicated no risk of Cd, Fe and Pb consumption in the vegetables. Geoaccumulation index revealed that Lafarge and Atoyo soils were extremely contaminated with Cd and Pb, respectively. Leafy vegetables grown in urban and rural floodplain soils adjacent to waste dumpsite are accumulators of Cd and Pb with food poisoning as the consequence.

Blood lead levels among Chinese children: The shifting influence of industry, traffic, and e-waste over three decades

In China, data relating to the historic prevalence of childhood lead poisoning suggest its pervasiveness. This review analysed published epidemiological data on blood lead levels (BLLs) of 735,271 Chinese children aged 0-6 between 1987 and 2017. Among these children, the geometric mean (GM) BLL was 95.1 μg/L (geometric SD = 1.62), and 24.1% suffered lead poisoning (BLL ≥ 100 μg/L). Importantly, there was a temporal decrease in the GM BLL value, from 182.9 μg/L in 1987-1991 to 42.4 μg/L in 2012-2017. However, a rebound was seen in the most recent two years (2016 and 2017). Moreover, the GM BLL among Chinese children has not fallen as low as U.S. children. This indicates that either (1) leaded petrol or lead based-paint exposure sources have not been adequately controlled in China, or (2) other pollution sources, such as industry, traffic, and e-waste, are impacting Chinese children. Drivers behind spatio-temporal variations were explored to provide scientific evidence regarding the prevention of childhood lead poisoning. We found that BLLs among children in the central and eastern areas of China have dropped lower than those in the western area, and that the GM BLL of children living in rural areas now exceeds children in urban areas. These reversals may be associated with the industrial decentralization policy of the late 1980s, when many heavily polluting industries and manufacturers moved away from cities on the east coast. It was discovered that the BLLs of children living in areas associated with mining have remained high (GM BLL = 155.0 μg/L for 2007-2017), and that the lead poisoning rate (LPR) has become exceptionally high in areas associated with e-waste. Finally, the review offers a data comparison with other countries, an overview of potentially influencing factors and sources, as well as some suggested prevention strategies to reduce childhood lead exposure.

Occurrence of priority trace metals in tomatoes (Solanum lycopersicum L.) from some areas of Uasin Gishu County, Kenya

This study determined the concentration of zinc, lead and cadmium in tomatoes consumed in some areas of Uasin Gishu, Kenya. Samples were taken in quintuplicate from Huruma and Bahati estates (Eldoret) and Chebaiywo (Kesses) and their metalliferous content were determined by atomic absorption spectroscopy. All samples had detectable levels of trace metals, with lead recording the highest concentration of 43.20 ± 0.31 mg/kg. Zinc concentrations were below WHO guidelines. Daily intakes ranged from 8.25 × to 2.59 × mg/kg/day. Though there are no probable cancer risks, hazard quotients indicated that deleterious health effects could arise from daily consumption of tomatoes.

Association between heavy metals and metalloids in topsoil and mental health in the adult population of Spain

BACKGROUND AND OBJECTIVES

Despite the biological plausibility of the association between heavy metal exposure and mental health disorders, epidemiological evidence remains scarce. The objective was to estimate the association between heavy metals and metalloids in soil and the prevalence of mental disorders in the adult population of Spain.

METHODS

Individual data came from the Spanish National Health Survey 2011-2012, 18,073 individuals residing in 1772 census sections. Mental health was measured with the 12-item General Health Questionnaire. The concentration estimates of heavy metal and metalloid levels in topsoil (upper soil horizon) came from the Geochemical Atlas of Spain based on 13,317 soil samples. Levels of lead (Pb), arsenic (As), cadmium (Cd) and manganese (Mn) were estimated in each census section by "ordinary Kriging". Odds ratios (OR) were calculated by multilevel logistic regression models.

RESULTS

Compared with the lowest Pb concentration levels quartile, the OR for the second quartile was 1.29 (95%CI: 1.11-1.50), increasing progressively to 1.37 (95%CI: 1.17-1.60) and 1.51 (95%CI: 1.27-1.79) in the third and fourth quartiles, respectively. For As, the association was observed in the third and fourth quartiles: 1.21 (95%CI: 1.04-1.41) and 1.42 (95% CI: 1.21-1.65), respectively. Cd was associated also following a gradient from the second quartile: 1.34 (95%CI: 1.15-1.57) through the fourth: 1.84 (95%CI: 1.56-2.15). In contrast, Mn only showed a positive association at the second quartile. Additionally, individuals consuming vegetables > once a day the OR for the fourth quartile of Pb concentration, vs. the first, increased to 2.93 (95%CI: 1.97-4.36); similarly for As: 3.00 (95%CI: 2.08-4.31), and for Cd: 3.49 (95%CI: 2.33-5.22).

CONCLUSIONS

Living in areas with a higher concentration of heavy metals and metalloids in soil was associated with an increased probability of having a mental disorder. These relationships were strengthened in individuals reporting consuming vegetables > once a day.

Hazardous heavy metals contamination of vegetables and food chain: Role of sustainable remediation approaches - A review

This review emphasizes the role of toxic metal remediation approaches due to their broad sustainability and applicability. The rapid developmental processes can incorporate a large quantity of hazardous and unseen heavy metals in all the segments of the environment, including soil, water, air and plants. The released hazardous heavy metals (HHMs) entered into the food chain and biomagnified into living beings via food and vegetable consumption and originate potentially health-threatening effects. The physical and chemical remediation approaches are restricted and localized and, mainly applied to wastewater and soils and not the plant. The nanotechnological, biotechnological and genetical approaches required to more rectification and sustainability. A cellular, molecular and nano-level understanding of the pathways and reactions are responsible for potentially toxic metals (TMs) accumulation. These approaches can enable the development of crop varieties with highly reduced concentrations of TMs in their consumable foods and vegetables. As a critical analysis by authors observed that nanoparticles could provide very high adaptability for both in-situ and ex-situ remediation of hazardous heavy metals (HHMs) in the environment. These methods could be used for the improvement of the inbuilt genetic potential and phytoremediation ability of plants by developing transgenic. These biological processes involve the transfer of gene of interest, which plays a role in hazardous metal uptake, transport, stabilization, inactivation and accumulation to increased host tolerance. This review identified that use of nanoremediation and combined biotechnological and, transgenic could help to enhance phytoremediation efficiency in a sustainable way.

Metal(loid) induced toxicity and defense mechanisms in Spinacia oleracea L.: Ecological hazard and Prospects for phytoremediation

A pot study was conducted to assess the phytoremediation potential of Spinach plants along with their physiological and biochemical response when grown in soil contaminated with heavy metal(loid)s (HMs). Plants were grown under different doses of Pb, Cd and As; and their metal(loid) accumulation efficiency was studied upon harvest; expressed in terms of bioabsorption coefficient (BAC), bioconcentration factor (BCF) and translocation factor (TF). Results showed significant (p ≤ 0.05) difference in physiological and biochemical mechanisms of plants as detected through decrease in concentration of cellular constituents (pigments, carbohydrates, total nitrogen content); and increase in antioxidants (both enzymatic and non-enzymatic). Despite of accumulating high amount of HMs in tissues, no visible signs of toxicity were seen; and hence the efficient survival and defense mechanism shown by spinach plants conclude that they are a viable option to be used for phytoremediation of sites contaminated with Cd and Pb. Since the content of Cd and Pb in edible part was higher than safe limits prescribed by USEPA, the present investigation also highlights the ecological hazards that may result upon cultivation of spinach in contaminated soil for agricultural purpose; or its accidental exposure to food chain when grown for phytoremediation.

Physiological response of spinach to toxic heavy metal stress

This study was carried out to investigate the concentration of two heavy metals, i.e., mercury (Hg) and arsenic (As) in soil and plant. Spinach (Spinacia oleracea L.) was used as a test vegetable in a pot experiment. Five spiked concentrations of both the metals along with sewage water were used as treatments. The analyses of the metals were determined in two cuttings. The results showed significant effect of treatments on the concentration of the two metals in soil and plant. The concentrations of As recorded were higher in 1st spinach cutting and reduced in the second harvest. However, comparing the two metal concentrations, it was found that As was absorbed greater as compared with Hg. Analyzing the plant growth parameter, it was found that metal stress has significantly influenced the plant growth. In sewage water pots, As was significantly higher than Hg. The transfer factor from soil to plant showed higher As in plants at lower concentration, but at higher As levels, the transfer rate declined, while Hg showed it was completely inverse. Positive correlation was found between soil applied metal concentration and plant uptake. It may be concluded from the above results that spinach is a good accumulator of heavy metals and has shown significant result of both As and Hg accumulation in plant. The concentration increased with the increasing concentration in soil.

Hazards assessment of the intake of trace metals by common mallow (Malva parviflora K.) growing in polluted soils

Human risks increase by consuming plants growing in trace/heavy metals contaminated soil irrigated with polluted water. The present study aims to assess the ability of common mallow to accumulate trace/heavy metals from polluted soils at South Greater Cairo, Egypt; and their hazardous effects on consumer's health. Five quadrats were used to collect soil and plant samples from three sites of un-polluted and polluted fields for chemical analysis and measurement of growth variables, as well as for assessing the daily intake of metals (DIM) and hazard quotient (HQ). Irrigation water analysis showed elevated concentrations of the investigated metals and mineral salts in the polluted area compared with the un-polluted one. Plant samples showed reduction in their growth parameters; as well as pigments and nutrient content in the metal-contaminated soil. In addition, Pb, Cd, Cu, Ni, Fe, Mn, Zn, and Co concentrations in the shoots and roots of plants grown in polluted fields were higher compared with plants grown in un-polluted site. The bioaccumulation and translocation factors of most investigated metals indicated the great ability of common mallow to accumulate such metals, which would increase the human intake of metals in their daily diets compared to their reference values (R_fD). The hazard quotient (HQ) of Pb, Cr, Fe, Mn and Zn for children and Pb, Cd, Fe and Mn for adults was >1, indicating health hazards for the consumers of common mallow cultivated in the polluted area.

Evaluation of antioxidant activities and essential/toxicmetal levels and their health risk assessment in citrus fruits from Pakistan

Fruits are important components of human diet, and their contamination by environmental pollutants is an emerging challenge nowadays. The present study is based on the measurement of selected essential and toxic trace metals including Na, K, Ca, Mg, Fe, Zn, Cu, Mn, Cr, Co, Sr, Li, Ni, Pb, and Cd in commercially available citrus fruits from Pakistan. The samples were digested in HNO₃ and HCLO₄ mixture, and the metal contents were quantified by flame atomic absorption spectrometry. Highest concentration was found for Ca (609.0-3596 mg/kg), followed by relatively higher levels of K (277.6-682.1 mg/kg), Mg (53.65-123.4 mg/kg), Na (1.173-52.14 mg/kg), and Fe (0.236-10.57 mg/kg), while Li, Ni, and Cd showed the lowest contributions in most of the samples. In addition, antioxidant activities such as DPPH radical scavenging assay, hydroxyl radical scavenging activity, ferrous chelating activity, ferric reducing antioxidant power assay, and phosphomolybdenum assay were also evaluated in the fruit samples. Considerably higher antioxidant activities were shown by grapefruit, mandarin, sweet lime, and tangerine. Most of the antioxidant assays were significantly correlated with Na, Mg, Fe, Mn, and Cu levels in the fruits. Human health risk was evaluated in terms of health risk index (HRI), target hazard quotient (THQ), and target cancer risk (TCR) which revealed insignificant health risks; thus, the consumption of these fruits can be considered as safe for human diet.

Trace Metal Accumulation in Trigonella foenum-graecum Irrigated with Wastewater and Human Health Risk of Metal Access Through the Consumption

The aim of the present research was to determine the trace metal accumulations in Trigonella foenum-graecum irrigated with three different water regimes (ground water, canal water and sugar mill water). Also, transfer factors, pollution load indices, and health risk indices were assessed to evaluate metal transport and accumulation through the food chain. The analysis was conducted by Atomic Absorption Spectrophotometer (Shimadzu model AA-6300) to evaluate the concentration of metals in water, soil and vegetables. Trace metal concentrations in water samples ranged from 0.84 to 1.67, 0.42 to 0.72, 0.45 to 0.85, 2.51 to 9.99, 1.21 to 1.92, 1.82 to 9.98 and 0.64 to 0.91 mg/kg for Cd, Cr, Cu, Fe, Ni, Zn and Mn, respectively. The mean metal concentrations in soil samples were determined as 0.25, 0.86, 0.96, 3.37, 0.4, 0.44 and 2.31 mg/kg for Cd, Cr, Cu, Fe, Ni, Zn and Mn, respectively. Trace metal accumulations in T. foenum-graecum samples gathered from where soil samples were taken are as follows: The contents of Cd, Cr, Cu, Fe, Ni, Zn and Mn ranged from 0.48 to 1.06, 0.11 to 0.35, 0.15 to 0.29, 1.43 to 8.39, 0.39 to 0.54, 2.1 to 3.05 and 0.42 to 0.47 mg/kg, respectively. Statistical analyses showed that the treatments have non-significant effect (p > 0.05) on concentrations of metals in T. foenum-graecum samples collected from three sites for Ni, Cr, Cu, Zn and Mn and significant effect on Fe and Cd.

Evaluation of toxic potential of metals in wheat crop grown in wastewater-contaminated soil in Punjab, Pakistan

The cheapest way of disposal of wastewater is its use in agriculture. The pressure in using fresh water resources may be alleviated by the domestic wastewater in agriculture. Wastewater holds significant quantity of plant nutrients like N, P, Ca, K, Co, Zn, and Mn. Therefore, it increases the crop yield. Triticum aestivum is the staple food crop for Pakistan, where it is an important caloric source. It is grown successfully in rain fed areas of the country as well as in irrigated areas with minimum water without losing its production potential. In this study, cadmium (Cd), nickel (Ni), iron (Fe), manganese (Mn), copper (Cu), chromium (Cr), zinc (Zn), and cobalt (Co) were evaluated; the effect of wastewater was studied on wheat variety (Punjab-2011) by applying different treatments of wastewater. In the comparison between five different treatments, in soil, Fe was the highest. The chromium in the current findings exceeded the permissible limit (0.03 mg/kg) in wheat grains. The reason of high Cr concentration might be due to the increased usage of wastewater for long periods. The level of pollution or the factor of contamination was the lowest for Zn and was highest for Cd in all treatments. Chromium has the lowest value of health risk index while Cd has the highest value in all treatments, indicating that exposed population is unlikely to experience obvious adverse effects on utilization of these contaminated grains of wheat.

Quantifying factors related to urban metal contamination in vegetable garden soils of the west and north of Melbourne, Australia

Vegetable gardens in cities provide communities with fresh vegetables but also may contribute towards public exposure to metals present in soil from historical pollution. Contamination of some Melbourne garden soils with Pb (range 12.9-773 mg kg^-1 in soil) was found with some soils exceeding the Australian human health screening criteria for residential land use of 300 mg kg^-1. Cadmium concentrations (0.12-1.04 mg kg^-1) were above the ambient background soil concentrations of <1 mg kg^-1. Nickel concentrations (7.6-40.5 mg kg^-1) and Cr (11.6-49.4 mg kg^-1) were within the range of expected ambient background concentrations. Distance from the nearest arterial road, house age and the likely use of lead-based paints were the main factors explaining approximately 75% of soil Pb variability in garden soils. Metal concentrations in garden soils of wooden houses were found to be significantly higher than the garden soil of brick and concrete houses (Pb (p < 0.0001)) and Cd (p < 0.001)). Significant correlations were found between backyard garden soil metal concentration and house age for Pb (R² = 0.83, p < 0.0001) and Cd (R² = 0.40, p < 0.0002) and the distance from arterial roads for Pb (R² = 0.38, p < 0.002), while Cr and Ni are related to soil characteristics cation exchange capacity, organic matter, and pH. Vegetable garden with elevated Pb and Cd had recognizable risk factors such as older, painted structures on adjacent houses and closer proximity to arterial roads with higher frequency traffic.

From environmental data acquisition to assessment of gardeners' exposure: feedback in an urban context highly contaminated with metals

Although growing vegetables in urban gardens has several benefits, some questions in relation with the safety of foods remain when the self-production is carried out on highly contaminated garden soils. To better assess the local population's exposure to Cd and Pb induced by the past activities of a lead smelter, a participatory program was initiated in 115 private kitchen gardens located in northern France to assist gardeners in understanding their soil environment. The challenge included contributing to the database of urban garden soils with the collection of a large number of samples: 1525 crops grouped into 12 types (leaf, fruiting, root, stem and bulbous vegetables, tubers, cabbages, leguminous plants, celeriac, fresh herbs, fruits, and berries), 708 topsoils, and 52 samples of self-produced compost. The main results were as follows: (i) topsoils were strongly contaminated by Cd and Pb compared to regional reference values; (ii) great variability in physicochemical parameters and metal concentrations in topsoils; (iii) the highest concentrations of Cd and Pb for celeriac and fresh herbs and the lowest for fruits and fruiting vegetables; (iv) a high percentage of vegetables that did not comply with the European foodstuff legislation; and (v) most self-produced compost samples were strongly contaminated. This study aimed to raise awareness and generate functional recommendations to reduce human exposure and to provide useful data that could be considered in other environmental contexts.

Health risk assessment of Pb and Cd in soil, wheat, and barley in Shazand County, central of Iran

BACKGROUND

Heavy metal contamination via mining activity is a serious problem around the world. This study was conducted to evaluate the total non-cancer hazard quotient (THQ) and excess lifetime cancer risks of lead (Pb) and cadmium (Cd) to different population groups via soil, wheat and barley ingestion, soil-dermal contact, and inhalation soil particulates around Shahin mine located in Shazand County.

METHODS

Soil and plants were sampled randomly from 60 agricultural fields around Shahin mine. The samples Pb and Cd concentrations were determined using atomic absorption spectroscopy (AAS). The THQ and the excess lifetime cancer risks of Pb and Cd were estimated using the formulas suggested by the U.S. Environmental Protection Agency (USEPA). The Pb non-cancer risk for children (<6 years old) was assessed using the integrated exposure uptake bio-kinetic (IEUBK) model.

RESULTS

The mean contents of Pb (234.47 mg kg^-1) and Cd (1.89 mg kg^-1) in soil samples were higher than the background values. The mean Pb and Cd concentrations in wheat grains were 0.44 and 0.23 μg g^-1 respectively, which were about 6.5 and 5.8 times higher than that was observed in barley grains, respectively. The THQ of Pb and Cd for all groups were greater than 1. The excess lifetime cancer risks of Pb via wheat and barley consumption for all receptor groups were greater than 1 × 10^-6.

CONCLUSIONS

Crop ingestion and soil inhalation had the greatest and lowest portions to increase the THQ and excess lifetime cancer risks of Pb and Cd in the study region, respectively.