The Bioaccumulation and Physiological Effects of Heavy Metals in Carrots, Onions, and Potatoes and Dietary Implications for Cr and Ni: A Review

A fluorescent probe for specific dual recognition of Ni2+ and pH

Nickel ion (Ni2+) and pH play an important role in environment and living organisms. A fluorescent probe "naphthalimide- s-triazine" (NCNS) for targeted dual detection of Ni2+ and pH was synthesized. As a result, NCNS exhibits excellent optical properties: a much larger Stokes shift (140 nm), eminent changes of fluorescence intensity and significant red-shift both for Ni2+ and pH. As for the detection of Ni2+, the selectivity is high and the anti-interference is strong. NCNS can fluorescently detect Ni2+ in a wider pH range from 4.0 to 10.5. It provides a much lower limit of detection (LOD, 20.03 nM), a rapid response time (150 s) and six times reversibility, showing the high sensitivity. Particularly, NCNS can be applied to fluorescently detect Ni2+ in actual water samples and HA-VSMC imaging. In the detection of pH, the probe generates a ratiometric fluorescence in a wide pH range (3.0 ∼ 12.3). NCNS has been successfully made test paper both for Ni2+ and pH. The mechanisms of the double recognition are verified by the density functional theory (DFT) calculations and the nuclear magnetic resonance (NMR) titration experiments.

Association between Mediterranean diet and metal mixtures concentrations in pregnant people from the New Hampshire Birth Cohort Study

Diet is a primary source of nutrients but also toxic metal exposure. In pregnancy, balancing essential metal exposure while reducing non-essential ones is vital for fetal and maternal health. However, the effect of metal mixtures from diets like the Mediterranean, known for health benefits, remains unclear. This study aimed to explore the association between Mediterranean diet adherence and metals exposure, both individually and as mixtures. The study involved 907 pregnant participants from the New Hampshire Birth Cohort Study. We calculated the relative Mediterranean diet score (rMED) through a validated food frequency questionnaire, which includes 8 traditional Mediterranean dietary components. Also, at ~24-28 weeks of gestation, we used ICP-MS to measure speciation of Al, Cd, Co, Cu, Fe, Hg, Mo, Ni, Sb, Se, Sn, Zn, and As in urine, as well as Pb, Hg, As, Ni, and Se in toenails. We used multiple linear regression and Weighted Quantile Sum regression to analyze the association between rMED and metal mixtures. The models were adjusted for age, pre-pregnancy BMI, smoking during pregnancy, and educational level. High adherence to the Mediterranean diet was associated with increased urinary Al (® = 0.26 (95 % confidence interval (CI) = 0.05; 0.46)), Cd (β = 0.12 (95%CI = 0.00; 0.24)), Mo (β = 0.10 (95%CI = 0.00; 0.20)), and AsB (β = 0.88 (95%CI = 0.49; 1.27)) as well as toenail Hg (β = 0.44 (95%CI = 0.22; 0.65)), Ni (β = 0.37 (95%CI = 0.06; 0.67)), and Pb (β = 0.22 (95%CI = 0.03; 0.40)) compared to those with low adherence. The intake of fruits and nuts, fish and seafood, legumes, cereals, meat, and olive oil were found to be related to the metal biomarkers within the rMED. In conclusion, the Mediterranean diet enhances essential metal intake but may also increase exposure to harmful ones.

Distribution and transport of contaminants in soil through mining processes and its environmental impact and health hazard assessment: A review of the prospective solutions

Environmental regulations were concerned with support in reaction to the enormous ecological harm caused by mining in the past. Because mining, dumping, and tailings can generate waste and radioactive consequences, society must develop methods for successfully treating mining waste from mine dumps, tailings, and abandoned mines. Strict policies associated with environmental regulations to avoid the possible dangers caused by garbage and radioactivity. Several characteristics, including background contamination from natural sources related to mineral deposits, contamination from industrial activities in three-dimensional subsurface space, a problem with long-term remediation following mine closure, a problem with secondary contaminated areas near mine sites, land use conflicts, and abandoned mines, distinguish it. Reusing and recycling mine waste occasionally results in cost-effective advantages in the mining sector by offsetting natural resource requirements and reducing the volume of garbage materials. These benefits stem from recycling and reusing mining waste, which can lower the amount of garbage that must be managed. This review focuses on realistic strategies for anticipating mining exploration control and attempts to examine those methods in-depth. Management strategies for limiting the environmental impact of mining dumps, stockpiles, and tailings were discussed. The environmental assessment was also mentioned to carry out specific control and take preventive actions.

Nickel in foodstuffs available on the Luxembourgish market and dietary intake

Nickel is a food contaminant of natural or anthropogenic origin. Monitoring of contaminants in food in general allows obtaining an overview on the presence of substances that are undesirable to health. The aim of this study was to analyse nickel content in food of non-animal origin and beverages sold in Luxembourg to determine the exposure of the population to this contaminant. In total, 660 samples were analysed in the timeframe from 2017 to 2021. The results demonstrate high concentrations of nickel in cashew nuts, walnuts, hemp and sunflower seeds, dried peas, oregano, and cocoa powder. Surveillance of contaminants in food allows identifying contributors to the chronic and acute exposure of nickel in order to potentially set official maximum levels in European legislation in the future, allowing for better enforcement actions in case of contaminated products and increasing consumer protection.

Assessment of the variation of heavy metals and pesticide residues in native and modern potato (Solanum tuberosum L.) cultivars grown at different altitudes in a typical mining region in Peru

This research paper presents the preliminary outcomes of an investigation conducted on the levels of heavy metals (such as As, Cd, Pb, Al, Mn, Cu, Ba, Cr, and Ni) and pesticide residues found in both traditional and modern potato cultivars grown in Moquegua, one of the principal copper-producing departments of Peru. A total of 160 samples of potatoes and soil were collected at altitudes between 58 and 3934 m above sea level (m.a.s.l.), and measured by inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectrometry (ICP-OES), respectively. Determinations of pesticide residues were conducted by using the QuEChERS method. Metal concentrations in potato samples varied from 0.006 to 0.215 mg/kg for Pb; 0.01-0.25 mg/kg for As; 0.001-0.048 mg/kg for Cd; 0.4-47.9 mg/kg for Al; 0.008-0.802 mg/kg for Cr; 0.505-2.729 mg/kg for Cu; 0.022-29.894 mg/kg for Mn; 0.03-2.76 mg/kg for Ba; to 0.006-0.419 mg/kg for Ni. Among the principal findings of the study were that (i) potatoes grown at lower altitude (Chala and Yunga regions) accumulated more As, Cr, Ni and Al than those grown at higher altitudes (Suni region); (ii) modern potatoes in most cases show a higher concentration of metals than native ones; (iii) the principal positive correlation found between soil and potatoes was for As; (iv) 90% of the samples analyzed were free from pesticide residues.

Hair and cord blood element levels and their relationship with air pollution, dietary intake, gestational diabetes mellitus, and infant neurodevelopment

BACKGROUND & AIMS

Exposure to a range of elements, air pollution, and specific dietary components in pregnancy has variously been associated with gestational diabetes mellitus (GDM) risk or infant neurodevelopmental problems. We measured a range of pregnancy exposures in maternal hair and/or infant cord serum and tested their relationship to GDM and infant neurodevelopment.

METHODS

A total of 843 pregnant women (GDM = 224, Non-GDM = 619) were selected from the Complex Lipids in Mothers and Babies cohort study. Forty-eight elements in hair and cord serum were quantified using inductively coupled plasma-mass spectrometry analysis. Binary logistic regression was used to estimate the associations between hair element concentrations and GDM risk, while multiple linear regression was performed to analyze the relationship between hair/cord serum elements and air pollutants, diet exposures, and Bayley Scales of infant neurodevelopment at 12 months of age.

RESULTS

After adjusting for maternal age, BMI, and primiparity, we observed that fourteen elements in maternal hair were associated with a significantly increased risk of GDM, particularly Ta (OR = 9.49, 95% CI: 6.71, 13.42), Re (OR = 5.21, 95% CI: 3.84, 7.07), and Se (OR = 5.37, 95% CI: 3.48, 8.28). In the adjusted linear regression model, three elements (Rb, Er, and Tm) in maternal hair and infant cord serum were negatively associated with Mental Development Index scores. For dietary exposures, elements were positively associated with noodles (Nb), sweetened beverages (Rb), poultry (Cs), oils and condiments (Ca), and other seafood (Gd). In addition, air pollutants PM2.5 (LUR) and PM10 were negatively associated with Ta and Re in maternal hair.

CONCLUSIONS

Our findings highlight the potential influence of maternal element exposure on GDM risk and infant neurodevelopment. We identified links between levels of these elements in both maternal hair and infant cord serum related to air pollutants and dietary factors.

Effect of exogenous taurine on growth, oxidative defense, and nickel (Ni) uptake in canola (Brassica napus L.) under Ni stress

Nickel (Ni) contamination and its associated hazardous effects on human health and plant growth are ironclad. However, the potential remedial effects of taurine (TAU) on Ni-induced stress in plants remain obscure. Therefore, the present study was undertaken to examine the effect of TAU seed priming (100 and 150 mg L‒1) as an alleviative strategy to circumvent the phytotoxic effects of Ni (150 mg kg‒1) on two canola cultivars (Ni-tolerant cv. Shiralee and Ni-sensitive cv. Dunkeld). Our results manifested an apparent decline in growth, biomass, photosynthetic pigments, leaf relative water content, DPPH free radical scavenging activity, total soluble proteins, nitrate reductase activity, and nutrient acquisition (N, P, K, Ca) under Ni toxicity. Further, Ni toxicity led to a substantial increase in oxidative stress reflected as higher levels of superoxide radicals (O2•‒) and hydrogen peroxide (H2O2) alongside increased relative membrane permeability, lipoxygenase (LOX) activity, and Ni accumulation in leaves and roots. However, TAU protected canola plants from Ni-induced oxidative damage through the amplification of hydrogen sulfide (H2S) production that intensified the antioxidant system to avert O2•‒, H2O2, and malondialdehyde (MDA) production. Further, TAU-mediated increase in H2S levels maintained membrane integrity that might have improved ionomics and bettered plant growth under Ni toxicity.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12298-023-01359-9.

Assessment of Heavy Metal Uptake in Potatoes Cultivated in a Typical Karst Landform, Weining County, China

The average content of heavy metals in Weining soil of karst landforms is generally higher than that of other agricultural regions. The aim of this study was to evaluate the heavy metal content in potatoes from Weining county and to analyze the correlation between the content of heavy metals in potatoes planted in the soil of karst landform and the soil’s environmental factors (soil heavy metals, soil pH, soil organic matter, altitude). Weining county (Guizhou province, China) is a typical karst landform, and has a potato production yield of 2.7 million tons. In this study, 56 soil and potato samples were collected from Weining county and the heavy metal content in the soils and potatoes was detected by inductively coupled plasma atomic mass spectrometry (ICP-MS). The content of Cr, Ni, and As in the soil was found to be higher, with almost half of the samples exceeding the maximum allowable levels. A total of 9 of the 56 samples tested had pollution load index values greater than 1.0, which indicates serious soil pollution. It was found that the ability of the potato to absorb heavy metals from the soil was very low, with the average bio-concentration factors of the metals Zn, Cu, Pb, Cr, Ni, and As being 0.087, 0.088, 0.0028, 0.0034, 0.0066, and less than 0.001, respectively. The content of the six heavy metals in the potatoes were all lower than the maximum permissible limit. The results show that a high As content in the soil could increase the content of Pb in potatoes, that a lower pH was beneficial to the bioaccumulation of Cr and Ni in potatoes, and that a high altitude is detrimental to the bioaccumulation of zinc and copper in potatoes. The HRI ranged between 1.12 × 10⁻² and 5.92 × 10⁻².

Heavy metals and health risk assessment in vegetables grown in the vicinity of a former non-metallic facility located in Romania

Soil contamination represents a serious and significant issue, especially when it comes to soil used in agricultural practices. This research was carried out in order to investigate the accumulation level of potentially toxic trace elements (Cr, Cd, Cu, Mn, Ni, Pb and Zn) in soil and vegetables (Solanum lycopersicum and Daucus carota). The transfer of the trace elements from soil to vegetables and the potential risk assessment were studied as well. Results indicated relatively high levels of heavy metals. Cd, Cu and Pb exceeded the alert limits established by the Romanian legislation. Zn was high as well. Positive correlations between the Cr, Cu and Pb indicated similar source of pollution, possibly related to the activities occurred in the non-metallic facility, nearby the study area. The heavy metals determined in the Solanum lycopersicum fruits and Daucus carota roots were below the maximum allowable concentrations, according to the WHO/FAO guideline. Slightly higher amounts of Cr and Cu were measured in tomatoes, compared to the carrots. Nevertheless, carrots were richer in Ni and Mn. The applied pollution indices indicated a contamination with heavy metals in 90% of the soil samples, with 9% probability of toxicity, the remaining 10% being classified into the precaution domain category. The plant bioconcentration of heavy metals into the Solanum lycopersicum fruits and Daucus carota roots is characterized using transfer factors. Generally, the results indicate that Daucus carota was the most susceptible to uptake Cu and Mn, while Solanum lycopersicum would rather uptake Cd and Zn. The estimated non-carcinogenic risk, based on the human health risk indices, indicates that the studied vegetables are safe for consumption with no impact on the human health. The results are lower than the critical value. Similarly, the carcinogenic risk indices results showed acceptable risks of cancer developing. It is important to assess and monitor the heavy metals levels in soil and in the vegetables intended to be consumed, in order to prevent contamination and potential negative effects on the environment and implicitly on the human health. The obtained data can be used in remediation techniques, as well as in implementing control measures of heavy metal contamination in soil and vegetables.

Mathematical Model to Simulate the Transfer of Heavy Metals from Soil to Plant

Heavy metals are naturally occurring elements, but their various applications have led to their wide circulation in the environment, raising concerns over their latent effects on the environment and human health. Their toxicity depends on numerous factors, including chemical species, concentration of heavy metal ions, environmental factors, etc. Experimental studies on the single or cumulative effects of heavy metals on plants are complex, time consuming and difficult to conduct. An alternative is mathematical modeling, which can include different factors into an integrated system and can predict plant and environmental behavior under multiple stressors. This paper presents a mathematical model that simulates the dependence of temperature, concentration of Zn in the soil and the subsequent bioaccumulation in lettuce (Lactuca sativa L.); respectively, the reaction of lettuce to Zn contamination. The main results consist of three mathematical models, based on systems of ordinary differential equations and checking their predictions with available experimental data. The models are applied to predict an optimal harvest time of lettuce with low concentration of Zn, in identifying the availability of the analyzed species to phytoremediation operations and the possibility of maneuvering certain control factors to reduce or increase the intensity of the bioaccumulation process.

Update of the risk assessment of nickel in food and drinking water

The European Commission asked EFSA to update its previous Opinion on nickel in food and drinking water, taking into account new occurrence data, the updated benchmark dose (BMD) Guidance and newly available scientific information. More than 47,000 analytical results on the occurrence of nickel were used for calculating chronic and acute dietary exposure. An increased incidence of post-implantation loss in rats was identified as the critical effect for the risk characterisation of chronic oral exposure and a BMDL 10 of 1.3 mg Ni/kg body weight (bw) per day was selected as the reference point for the establishment of a tolerable daily intake (TDI) of 13 μg/kg bw. Eczematous flare-up reactions in the skin elicited in nickel-sensitised humans, a condition known as systemic contact dermatitis, was identified as the critical effect for the risk characterisation of acute oral exposure. A BMDL could not be derived, and therefore, the lowest-observed-adverse-effect-level of 4.3 μg Ni/kg bw was selected as the reference point. The margin of exposure (MOE) approach was applied and an MOE of 30 or higher was considered as being indicative of a low health concern. The mean lower bound (LB)/upper bound (UB) chronic dietary exposure was below or at the level of the TDI. The 95th percentile LB/UB chronic dietary exposure was below the TDI in adolescents and in all adult age groups, but generally exceeded the TDI in toddlers and in other children, as well as in infants in some surveys. This may raise a health concern in these young age groups. The MOE values for the mean UB acute dietary exposure and for the 95th percentile UB raises a health concern for nickel-sensitised individuals. The MOE values for an acute scenario regarding consumption of a glass of water on an empty stomach do not raise a health concern.

Nutrients and non-essential elements in edible crops following long-term mineral and compost fertilization of a Mediterranean agricultural soil

The effects of long-term soil fertilizations on nutrient and non-essential element concentrations in edible parts of three crops important in human diet were investigated repeating four treatments (biowaste compost, biowaste compost plus mineral nitrogen, mineral NPK, unfertilized control) for seven consecutive years (2007-2014). Fruits of Solanum lycopersicum cv San Marzano collected in 2011 and 2012, bulbs of Allium cepa cv Bianca di Pompei collected in 2012 and 2013, and bulbs of Foeniculum vulgare cv Orbit collected in 2014 were analyzed. Wide variations in element concentrations were observed along time and among species, with Ca, K, Mg, and Na higher in fennel bulbs and Cd, Cr, Mn, Ni, Pb, and Zn higher in tomato fruits, where Cd reached concentrations up to ninefold higher than the permitted values (EU Regulation n. 488/2014). Despite the enrichments in soil total Cu and available Cd, Fe, K, Mn, and Zn concentrations due to long-term fertilization with biowaste compost (alone or with mineral fertilizers), plants showed lower micronutrient and non-essential element concentrations in respect to those on unfertilized soils. Considering the potential toxicity for human beings of these mobile and persistent elements, the obtained findings reassure on the safe use of biowaste compost in agriculture. Overall, this study suggests the use of compost as the most advisable fertilization practice and highlights the need of multiple crops analysis in evaluating the effects of long-term soil fertilization on their chemical composition.

Effects of Heavy Metal Exposure on Shipyard Welders: A Cautionary Note for 8-Hydroxy-2'-Deoxyguanosine

Oxidative stress plays a crucial role in the development of diseases induced by welding fumes. To our knowledge, little information is available on the relationship between multiple heavy metal exposure and oxidative stress in welders. We assessed the relationship between multiple heavy metal exposure and oxidative damage by analyzing 174 nonsmoking male welders in a shipyard. Urinary metals were used as the internal dose of exposure to metals in welding fumes, and urinary 8-hydroxy-2’-deoxyguanosine (8-OHdG) was used as an oxidative DNA damage marker. The relationship between workers’ metal levels and 8-OHdG was estimated using a multiple linear regression model. The geometric mean levels of urinary chromium (Cr), nickel (Ni), cadmium (Cd), and lead (Pb) were considerably higher in welders than in controls. Urinary Cr and Ni were determined as effective predictors of urinary 8-OHdG levels after adjusting for covariates. Oxidative DNA damage was associated with both Cr and Ni of welding fume exposure in shipyard welders (Ln Cr: β = 0.33, 95%C.I. = 0.16–0.49; Ln Ni: β = 0.27, 95%C.I. = 0.12–0.43). In this study, we investigated the significantly positive relationship between urinary metals (especially Cr and Ni) and 8-OHdG in nonsmoking shipyard welders. Moreover, the use of particulate respirators did not reduce metal exposure and oxidative damage. Therefore, we infer that hazard identification for welders should be conducted.

Distribution and Redistribution of 109Cd and 65Zn in the Heavy Metal Hyperaccumulator Solanum nigrum L.: Influence of Cadmium and Zinc Concentrations in the Root Medium

Heavy metal redistribution is relevant for the quality of edible crops and the suitability of hyperaccumulators for bioremediation. Root-to-shoot transfer via the xylem and redistribution in the aerial parts via the phloem differ between various heavy metals. In general, cadmium is more slowly released to the shoot than zinc (e.g., in wheat, bean, and lupin). However, rapid cadmium transport to the shoot was detected in the hyperaccumulator Solanum nigrum L. This is a key aspect in this article and might be important for bioremediation. The radionuclides ¹⁰⁹Cd and ⁶⁵Zn were used to investigate the respective influence of elevated cadmium or zinc in the root medium on the dynamics of the two heavy metals in S. nigrum. Although transport via the xylem to the leaves was similar for ¹⁰⁹Cd and ⁶⁵Zn, the further redistribution from older leaves to younger leaves, flowers, and fruits via the phloem was far less efficient for ¹⁰⁹Cd than for ⁶⁵Zn. Furthermore, the redistribution of ¹⁰⁹Cd within the shoot was negatively influenced by increased cadmium (but not by increased zinc) concentrations in the nutrient medium. The redistribution of ⁶⁵Zn in the shoot was selectively decreased by increased zinc concentrations (but generally not by cadmium).

Regulation of antioxidant production, ion uptake and productivity in potato (Solanum tuberosum L.) plant inoculated with growth promoting salt tolerant Bacillus strains

The exchangeable sodium (Na⁺) in salt affected soils is a major constraint in potassium (K⁺) availability to plants that disturb ion transport and inhibit plant growth, adversely. Salt tolerant plant growth promoting rhizobacteria (PGPR) may regulate the Na⁺/K⁺ efflux and increase K⁺ uptake by the plant from the soil. Therefore, a pot study was performed to examine the effect of salt tolerant PGPR Bacillus sp. alone and in consortium, on antioxidant enzyme activity, ion uptake and potato (Solanum tuberosum L.) tuber yield in normal and salt affected soils. We observed that Bacillus sp. (strains SR-2-1 and SR-2-1/1) solubilized insoluble phosphorous and produced indole-3-acetic acid while only SR-2-1/1 produced ACC deaminase in culture medium supplemented with various concentrations of NaCl (0-6%). In the pot experiment, the consortium treatment of strains was found to increase relative leaf water contents whereas decreased the electrolyte leakage and antioxidant enzyme activity both in normal and salt affected soils. Similarly, consortium treatment decreased Na⁺ whereas increased K⁺, Ca⁺², K⁺/Na⁺ and Ca⁺²/Na⁺ in plant dry matter in both soils. It has been investigated that inoculation of PGPR significantly (p < 0.05) increased plant biomass, number of tubers per plant and tuber weight as compared to un-inoculated plants in both soils. In addition, PGPR inoculation enhanced auxin production in root exudates of young potato plants and bacterial population dynamics in both soils. Na⁺ ion regulation (R² = 0.95) and tuber weight (R² = 0.90) in salt affected soil were significantly correlated with auxin production in the rhizosphere. Results of this study conferred that consortium of Bacillus strains (SR-2-1, SR-2-1/1) enhanced auxin production in the rhizosphere of potato plants and that ultimately regulated antioxidant enzyme production and uptake of Na⁺, K⁺ and Ca⁺² in potato plants resulted into a higher tuber yield in both normal and salt affected soils.

Effects of soil amendments on the growth response and phytoextraction capability of a willow variety (S. viminalis × S. schwerinii × S. dasyclados) grown in contaminated soils

This study was conducted to evaluate the effects of lime and bisphosphonates (BPs) such as N10O chelate amendment on the growth, physiological and biochemical parameters, and phytoextraction potential of the willow variety Klara (Salix viminalis × S. schwerinii × S. dasyclados) grown in soils heavily contaminated with copper (Cu), nickel (Ni) and zinc (Zn). The plants were irrigated with tap or processed water (mine wastewater). The results suggest that the combined effects of the contaminated soil and processed water inhibited growth parameters, gas exchange parameters and chlorophyll fluorescence (Fv/Fm) values. In contrast, malondialdehyde (MDA) content, organic acids, total phenolic and total flavonoid contents, and the accumulation of metals/metalloids in the plant tissues were increased compared to the control. When the soil was supplemented with lime and N10O; growth, physiological, biochemical parameters, and resistance capacity were significantly higher compared to unamended soil treatments, especially in the contaminated soil treatments. The combined lime‒ and N10O‒amended soil treatment produced higher growth rates, resistance capacity, photosynthesis rates and phytoextraction efficiency levels relative to either the lime‒amended or the N10O‒amended soil treatments. This study provides practical evidence of the efficient chelate‒assisted phytoextraction capability of Klara and highlights its potential as a viable and inexpensive novel approach for in situ remediation of Cu‒, Ni‒ and Zn‒contaminated soils and mine wastewaters.

Assessment of potentially toxic trace element contamination in urban allotment soils and their uptake by onions: A preliminary case study from Sheffield, England

Toxic trace element (TTE) contamination in urban soils may pose potential health risks, especially in cities with previous industrial activities. This study aimed to investigate soil contamination in urban allotments in Sheffield, the uptake of TTEs in autumn and spring sown onions (Allium cepa), and their potential risks on human health via consumption of the crops. Paired soil and plant samples were taken in triplicates from four private allotments to assess potentially elevated levels of lead (Pb), zinc (Zn), copper (Cu), arsenic (As), and chromium (Cr). These elements in soils exceeded the ambient background levels for England. Both Pb and As exceeded some UK and EU soil tolerable limits. Concentration factors (CF) were calculated as the ratio of trace element in the plant as compared to that in the soil, and uptake rates were in the order Zn>Cu>Cr>Pb>As. Concentrations were higher for most TTEs in spring sown onions (SSO), and had significantly higher CF (p < 0.05) for Pb and Cr than autumn sown onions (ASO), whereas the opposite was true for As. Toxic elements in plants did not exceed FAO/WHO intake limits when considering TTE content per plant and consumption rates. Human health risk assessment calculations using target hazard quotients (THQ) and hazard indexes (HI) indicated that consuming onions alone did not pose an immediate health risk.

Increased prevalence of Sjogren's syndrome in where soils contain high levels of chromium

Previously, we showed that farm soil levels of chromium were strongly correlated with people's serum chromium levels and an increase (3.6 fold) in both the incidence and prevalence of sicca syndrome in areas where farm soil chromium was high. Because Sjogren's syndrome (SS) is the major disease causing a dry mouth and dry eyes, we aimed in the study to investigate whether these areas with high soil chromium have a high SS prevalence. We used a database from the authority in charge of catastrophic illness certificates. Heavy metal concentrations in farm soils were retrieved from nationwide surveys. We used spatial regression models to study the relationships between the SS prevalence and soil metal concentrations. There were 11,220 people, 1165 men and 10,055 women who received a SS certificate from 2000 to 2011. The SS prevalence was 31 per 105 people, 5.59 for men and 55.01 for women. The highest SS prevalence in Taiwan (53 per 105) was located in an area where farm soils contain the highest amounts of chromium. In contrast, other types of heavy metal did not show such a strong association. In conclusion, the SS prevalence is significantly increased in areas where soils contain high levels of chromium. Chromium is likely a risk for SS.

Environmental Chemical Contaminants in Food: Review of a Global Problem

Contamination by chemicals from the environment is a major global food safety issue, posing a serious threat to human health. These chemicals belong to many groups, including metals/metalloids, polycyclic aromatic hydrocarbons (PAHs), persistent organic pollutants (POPs), perfluorinated compounds (PFCs), pharmaceutical and personal care products (PPCPs), radioactive elements, electronic waste, plastics, and nanoparticles. Some of these occur naturally in the environment, whilst others are produced from anthropogenic sources. They may contaminate our food-crops, livestock, and seafood-and drinking water and exert adverse effects on our health. It is important to perform assessments of the associated potential risks. Monitoring contamination levels, enactment of control measures including remediation, and consideration of sociopolitical implications are vital to provide safer food globally.

Full-color emissive carbon-dots targeting cell walls of onion for in situ imaging of heavy metal pollution

Full-colour emissive carbon-dots were prepared and applied in targeting onion CWs for in situ imaging of heavy metal pollution.

Combined application of compost and Bacillus sp. CIK-512 ameliorated the lead toxicity in radish by regulating the homeostasis of antioxidants and lead

Lead (Pb) contamination is ubiquitous and usually causes toxicity to plants. Nevertheless, application of compost and plant growth promoting rhizobacteria synergistically may ameliorate the Pb toxicity in radish. The present study assessed the effects of compost and Bacillus sp. CIK-512 on growth, physiology, antioxidants and uptake of Pb in contaminated soil and explored the possible mechanism for Pb phytotoxicity amelioration. Treatments comprised of un-inoculated control, compost, CIK-512, and compost + CIK-512; plants were grown in soil contaminated with Pb (500mgkg^-1) and without Pb in pot culture. Lead caused reduction in shoot dry biomass, photosynthetic rate, stomatal conductance, relative water contents, whereas enhanced root dry biomass, ascorbate peroxidase, catalase, malondialdehyde and electrolyte leakage in comparison with non-contaminated control. Plants inoculated with strain CIK-512 and compost produced significantly higher dry biomass, photosynthetic rate and stomatal conductance in normal and contaminated soils. Bacterial strain CIK-512 and compost synergy improved growth and physiology of radish in contaminated soil possibly through homeostasis of antioxidant activities, reduced membrane leakage and Pb accumulation in shoot. Possibly, Pb-induced production of reactive oxygen species resulted in increased electrolyte leakage and malondialdehyde contents (r = 0.88-0.92), which led to reduction in growth (r = -0.97) and physiology (r = -0.38 to -0.80), however, such negative effects were ameliorated by the regulation of antioxidants (r = 0.78-0.87). The decreased activity of antioxidants coupled with Pb accumulation in aerial part of the radish indicates the Pb-phytotoxicity amelioration through synergistic application of compost and Bacillus sp. CIK-512.

Metal bioaccumulation and mutagenesis in a Tradescantia clone following long-term exposure to soils from urban industrial areas and closed landfills

Soil mutagens, particularly metals, may persist long after the source of pollution has been removed, representing a hazard to plants, animals, and humans in or near contaminated areas. Often, due to urban growth, previous land uses may be forgotten and hazards overlooked. We exposed Tradescantia clone #4430 plants to soil from two industrial areas (with different former uses) and two urban waste landfills in the city of Vilnius, all of which were long disused. Two modes of exposure were used: long-term exposure of growing plants in test soils for 0.5 or 1.0y, and short-term exposure of cuttings to water and dimethyl sulfoxide (DMSO) soil extracts. An increased frequency of micronuclei (MN) was observed with both modes of exposure. The concentrations of 24 metals and other elements were analyzed in the test soils and in above-ground plant parts, under both exposure modes, and the concentration coefficients (Cc) for various elements, the total contamination index (Zs) for soils and plants, and the bioaccumulation factor (BAF) for plants were calculated. These measurements allow a comparison of the contamination levels of soils and plants with equalized values. Metal accumulation levels in plants and soils showed significant differences, providing a better understanding of the genotoxicity of soils from closed landfills and highlighting the need to determine the concentrations of metals and other genotoxicants in plants in relation to genotoxicity.

Μetal Uptake by Sunflower (Helianthus annuus) Irrigated with Water Polluted with Chromium and Nickel

The water aquifers of the regions of Asopos River in Viotia and Messapia in Evia (Greece) have been contaminated with hexavalent chromium (Cr (VI)) and bivalent nickel (Ni (II)). Given that these areas are the two biggest tuber producing regions of Greece, in our previous work, the cross-contamination of the food chain with these two heavy metals was quantified. In the present study, the potential of sunflower (Helianthus annuus) cultivation in these regions is evaluated. The scope of our study was to investigate the uptake of chromium and nickel by sunflower, in a greenhouse experiment. The study included two cultivation periods of plants in six irrigation lines with different levels of Cr (VI) and Ni (II) ranging from 0 μg/L (control) to 10,000 μg/L. In all plant parts, statistically significant increased levels of Cr (VI) and Ni (II) were found when compared to control ones. Also, a positive correlation, both for Cr and Ni, between levels of heavy metals in irrigation water and plants was observed. Following European Food Safety Authority recommendations, the obtained oil was evaluated as safe for consumption, therefore, sunflower cultivation could be a valid bioremediation solution for the Asopos and Messapia regions.

Metal-contaminated potato crops and potential human health risk in Bolivian mining highlands

This study assessed metals in irrigation water, soil and potato crops impacted by mining discharges, as well as potential human health risk in the high desert near the historic mining center of Potosí, Bolivia. Metal concentrations were compared with international concentration limit guidelines. In addition, an ingested average daily dose and minimum risk level were used to determine the hazard quotient from potato consumption for adults and children. Irrigation water maximum concentrations of Cd, Pb and Zn in mining-impacted sites were elevated 20- to 1100-fold above international concentration limit guidelines. Agricultural soils contained total metal concentrations of As, Cd, Pb and Zn that exceeded concentration limits in agricultural soil guidelines by 22-, 9-, 3- and 12-fold, respectively. Potato tubers in mining-impacted sites had maximum concentrations of As, Cd, Pb and Zn that exceeded concentration limits in commercially sold vegetables by 9-, 10-, 16- and fourfold, respectively. Using conservative assumptions, hazard quotients (HQ) for potatoes alone were elevated for As, Cd and Pb among children (range 1.1-71.8), in nearly all of the mining-impacted areas; and for As and Cd among adults (range 1.2-34.2) in nearly all of the mining-impacted areas. Only one mining-impacted area had a Pb adult HQ for potatoes above 1 for adults. Toxic trace elements in a major regional dietary staple may be a greater concern than previously appreciated. Considering the multitude of other metal exposure routes in this region, it is likely that total HQ values for these metals may be substantially higher than our estimates.

Assessment of cadmium content of potato grown in Weining County, Guizhou Province, China

A total of 54 soil and 54 potato samples have been collected from Weining County to evaluate the accumulation of cadmium in potatoes. The concentrations of the total Cd and the available Cd in the soil samples have been detected. The total concentrations of Cd were from 0.41 to 10.0 mg/kg with an average value of 2.60 mg/kg in soil. The concentrations of available Cd in the soil were 0.07 to 3.47 mg/kg with an average value of 0.59 mg/kg. The concentration of the available Cd showed a good linear positive correlation with the total Cd content in the soil. For the 54 potato samples, the Cd concentrations were from 0.023 to 0.18 mg/kg with an average value 0.083 mg/kg (fresh weight).The bioconcentration factor (BCF) values of Cd in potatoes, based on dry weight, were from 0.02 to 0.96 with an average value 0.24. The uptake of cadmium by plants is dependent on various soil and environmental factors. A regression model to predict the concentration of cadmium in Weining potatoes based on soil properties and elevation was developed. The results showed the elevation and the soil pH played an important role and had a negative influence on the uptake of Cd by potato in Weining County. The mean intake of Cd by adults through consumption of potato from Weining would be 5.9 μg/day, and it is well below the provisionally tolerable daily intake for Cd (70 μg/day).

Carotenoids and Antioxidant Enzymes as Biomarkers of the Impact of Heavy Metals in food Chain

Antioxidant enzymes (catalase and peroxidase) and carotenoids lutein and β-carotene are often used as biomarkers of metal contamination of water and agricultural soils. In this study, the effects of heavy metals present in irrigation water on the aforementioned carotenoids of potatoes Solanum tuberosum L. and carrots Daucus carota L., cultivated in a greenhouse and irrigated with a water solution including different levels of Cr(VI) and Ni(II) were investigated. These results were compared to the levels of the same metabolites that had been assessed in market-available potato and carrot samples. The findings indicated that the levels of the examined metabolites on the treated with Cr and Ni samples, resemble the levels of the same parameters in the market samples, originating from polluted areas. Therefore, the antioxidant enzymes, catalase and peroxidase, and the carotenoids, lutein and β-carotene, could be handled as indicators of heavy metal pollution.

Coevolution between Cancer Activities and Food Structure of Human Being from Southwest China

Yunnan and Tibet are the lowest cancer mortality and the largest producer for anticancer crops (brown rice, barley, buckwheat, tea, walnut, mushrooms, and so forth). Shanghai and Jiangsu province in China have the highest mortality of cancers, which are associated with the sharp decline of barley.

Concentration levels of selected essential and toxic metals in potato (Solanum tuberosum L.) of West Gojjam, Amhara Region, Ethiopia

Potato (Solanum tuberosum L.) is one of the most widely used as a staple food crop for human diets. It is an excellent source of minerals. In this study, contents of Ca, Mg, Fe, Zn, Cd and Pb in potato cultivars cultivated in Yilmana Densa, and Mecha districts of the West Gojjam zone, Ethiopia were determined by flame atomic absorption spectrometry. A 0.50 g oven-dried potato sample was digested using a mixture of 10 mL HNO₃:HClO₄ (4:1 v/v) at 120 °C for 3 h. The concentration ranges in dry weight basis in decreasing order were: Mg (420–438 mg/kg) > Ca (176–254 mg/kg) > Fe (27.3–90.4 mg/kg) > Zn (20.6–77.7 mg/kg) > (2.00–17.4 mg/kg) for Pb. The toxic heavy metal Cd was below the limit of detection in all the analyzed samples (<0.1 mg/kg). The Mg found in highest contents while Fe was the most abundant microelement. The Cd was found below the provisional maximum tolerable daily intake of WHO/FAO and European Commission (EC) while Pb was above the limit. A wide range of variations was observed in the metal contents of potato cultivars collected from the two districts. Potato cultivars grown in West Gojam zone of Ethiopian could contribute a substantial amount of Fe and Zn together with the major elements, Ca and Mg to the individual’s daily dietary needs if consumed on a regular basis.

Relation between magnetic parameters and nematode abundance in agricultural soils of Portugal--a multidisciplinary study in the scope of environmental magnetism

Soil is composed of different types of particles which are either natural or of anthropogenic origin. Anthropogenic particles are often related to the presence of heavy metals and thus provide information on soil quality. Magnetic parameters can detect the presence of such particles and may be used as a proxy for environmental pollution. This study explores the relationships between magnetic particles and the nematofauna of agricultural soils. Magnetic, pedological, microscopy and nematological analyses were conducted in soils collected from major regions of potato production in Portugal. The magnetic characterisation of soils identified regions with magnetic particles with possible anthropogenic origin. Microscopy analysis revealed the presence of spherical particles dominantly composed of Fe, O and C. A positive and significant relationship was found between saturation isothermal remanent magnetisation (SIRM) and mass-specific susceptibility (χ), confirming the importance the ferrimagnetic fraction to magnetic properties. The nematode communities were composed of nematodes belonging to four trophic groups (bacterial feeding, plant feeders, fungal feeders and omnivores/predators). The relationships between magnetic parameters and the nematodes showed that (1) S-25 has a linear correlation with number of nematodes per kilogram of soil and with plant feeders' trophic group and (2) SIRM correlates with the bacterial feeders trophic group. This study reveals that magnetic proxies may provide means for detecting regions with higher levels of pollution, possibly related to heavy metals. Due to the large background variability found in magnetic parameters, the sampling spacial mesh should to be further refined and the input of magnetic minerals needs to be locally calibrated.