Non-Uniform Bioaccumulation of Lead and Arsenic in Two Remote Regions of the Human Heart's Left Ventricle: A Post-Mortem Study.

The extent of heavy-metal-induced cardiotoxicity is proportional to the levels of metal bioaccumulation, and it was previously assumed that heavy metals accumulate uniformly in the myocardium. Therefore, the aim of this study was to investigate concentrations of metals and metalloids in two distant regions of the left ventricle (LV), the base of the LV, and apex of the LV using inductively coupled plasma mass spectrometry (ICP-MS). We also examined the potential correlation between metal levels and the thickness of the interventricular septum in twenty LV specimens (ten from the base of LV and ten from the apex of LV) from 10 individuals (mean age 75 ± 6 years). We found significantly higher concentrations of arsenic and lead in the LV apex compared to the base of the LV. We also found a positive correlation between the concentrations of arsenic in the myocardium of LV and the thickness of the interventricular septum. Our results indicate that arsenic and lead accumulate to a higher extent in the apex of the LV compared to the base of the LV. Therefore, future studies designed to measure levels of metals in heart muscle should consider non-uniform accumulation of metals in the myocardium.

Bioavailability and health risk of toxic heavy metals (As, Hg, Pb and Cd) in urban soils: A Monte Carlo simulation approach.

Toxic heavy metals pollution in urban soil has become a major global issue due to its adverse effects on the environment and human health. In this paper, 26 soil samples were analyzed to assess the speciation, bioavailability and human health risk of Arsenic (As), Mercury (Hg), Lead (Pb) and Cadmium (Cd) in urban soils of a heavy industrial city in NE China by using a Monte Carlo simulation approach. The results showed that As, Hg, Pb and Cd concentrations in the soil all exceed the corresponding background value of study area. Mercury displays the highest value of geo-accumulation index (Igeo), followed by Cd, Pb and As. The pollution load index (PLI) value (>2) indicates a moderate pollution level in the study area. The chemical speciation of HMs mainly exists in residual fraction except Cd. The probabilistic health risk assessment demonstrated that the mean values of Total Carcinogenic Risk (TCR) and Hazard Index (HI) calculated with total concentration are at the unacceptable level, with a higher risk to children than adults. However, the mean values calculated with bioavailable fraction are all within the acceptable level. The mean value of TCR and HI obtained by bioavailable fraction is about 96% and 95% lower than that obtained by total concentration, respectively. Thus, this study suggested that the bioavailable fraction of HMs is a more reliable parameter for health risk assessment, while the total concentration of HMs can overestimate the true risk. The results of this study provide some insight into the speciation, bioavailability and health risks of toxic heavy metals in urban soils in those heavy industrial cities.

Effects of environmental and occupational lead toxicity and its association with iron metabolism.

BACKGROUND: Discrepancies are present in the findings from clinical trials evaluating a physiological role of iron status in the lead-exposed population. OBJECTIVE: The purpose of this article was to summarize the current understanding of cellular mechanisms of lead toxicity and present a comprehensive review of existing clinical trials related to associations of lead poisoning and iron status. Although an association of iron metabolism pathways that are affected by lead intoxication has been studied, there are still aspects that remain to be elucidated. The existence of additional Pb uptake pathways besides DMT1 transporter-mediated is postulated to non-specifically regulate lead absorption. METHODS: Authors performed a systematic search of PubMed, EMBASE® and Web of Science databases to identify studies that reported an association between health risks of non-organic lead that are associated with iron status markers as possible effect modifier. RESULTS: There were 58 studies that met the pre-defined inclusion criteria for the systematic review. There is a strong body of evidence supporting the hypothesis that alleviated blood lead level can be correlated with a reduced body iron store and increasing the risk of anemia. This association is of a high significance in cases of a young adolescent, weaker in groups of older children and often without a statistical significance in adults. DISCUSSION: Discrepancies in the observations may result from different specificities of lead absorption pathways in children and adults, as well as the power of the statistical tests in varying population sizes. It may be assumed that the extent of iron deficits coupled together with source, timing, and severity of lead exposure, significantly influence the correlation between these factors. Some of the intervention programs of counteracting lead poisoning by iron supplementation proved to be effective and may be a promising prevention strategy for the exposed population.

Concomitant oral intake of purified clinoptilolite tuff (G-PUR) reduces enteral lead uptake in healthy humans.

Lead exposure can cause substantial organ damage. Enteral lead absorption may be reduced by concomitant intake of clinoptilolite tuff, a zeolite from natural sources. This study aimed to assess the effect of purified clinoptilolite tuff (G-PUR) on enteral lead uptake in adults using stable lead isotope 204Pb as a tracer. In this randomized, placebo-controlled, double-blind, parallel-group study, 42 healthy participants were randomized to receive oral G-PUR 2.0 g, 2 * 2.0 g, or placebo, together with 2.5 µg of 204Pb in water. The enrichment of 204Pb caused by the tracer in blood and urine was measured by mass spectrometry. G-PUR was well tolerated. The mean maximum 204Pb enrichment of 0.505% of total blood lead was significantly higher (p < 0.0001) in the placebo group compared to G-PUR 2.0 g (0.073%) or G-PUR 2 * 2.0 g (0.057%) group. Normalized 204Pb AUC0-192 was 86.5, 11.9, and 8.5% * h without and with G-PUR 2.0 g, and G-PUR 2 * 2.0 g, respectively (p < 0.0001 vs. placebo). This smaller 204Pb exposure was paralleled by a reduced urinary excretion in subjects receiving G-PUR. Concomitant oral intake of purified clinoptilolite tuff reduced enteral uptake of 204Pb in healthy humans by approximately 90%. The reduced bioavailability is demonstrable by a decrease of 204Pb tracer enrichment in blood and urine.Trial registration: clinicaltrials.gov identifier: NCT04138693, registered 24/10/2019.

Bioavailability of arsenic, cadmium, lead and mercury as measured by intestinal permeability.

In this study, the intestinal permeability of metal(loid)s (MLs) such as arsenic (As), cadmium (Cd), lead (Pb) and mercury (Hg) was examined, as influenced by gut microbes and chelating agents using an in vitro gastrointestinal/Caco-2 cell intestinal epithelium model. The results showed that in the presence of gut microbes or chelating agents, there was a significant decrease in the permeability of MLs (As-7.5%, Cd-6.3%, Pb-7.9% and Hg-8.2%) as measured by apparent permeability coefficient value (Papp), with differences in ML retention and complexation amongst the chelants and the gut microbes. The decrease in ML permeability varied amongst the MLs. Chelating agents reduce intestinal absorption of MLs by forming complexes thereby making them less permeable. In the case of gut bacteria, the decrease in the intestinal permeability of MLs may be associated to a direct protection of the intestinal barrier against the MLs or indirect intestinal ML sequestration by the gut bacteria through adsorption on bacterial surface. Thus, both gut microbes and chelating agents can be used to decrease the intestinal permeability of MLs, thereby mitigating their toxicity.

An interlaboratory evaluation of the variability in arsenic and lead relative bioavailability when assessed using a mouse bioassay.

Animal bioassays have been developed to estimate oral relative bioavailability (RBA) of metals in soil, dust, or food for accurate health risk assessment. However, the comparability in RBA estimates from different labs remains largely unclear. Using 12 soil and soil-like standard reference materials (SRMs), this study investigated variability in lead (Pb) and arsenic (As) RBA estimates employing a mouse bioassay in 3 labs at Nanjing University, University of Jinan, and Shandong Normal University. Two performances of the bioassay at Nanjing University in 2019 and 2020 showed reproducible Pb and As RBA estimates, but increasing the number of mouse replicates in 2020 produced more precise RBA measurements. Although there were inter-lab variations in diet consumption rate and metal accumulation in mouse liver and kidneys following SRM ingestion due to differences in diet composition, bioassays at 3 labs in 2019 yielded overall similar Pb and As RBA estimates for the 12 SRMs with strong linear correlations between each 2 of the 3 labs for Pb (R2 = 0.95-0.98 and slope = 0.85-1.02) and As RBA outcomes (R2 = 0.46-0.86 and slope = 0.56-0.79). The consistency in RBA estimates was attributed to the relative nature of the final bioavailability outcome, which might overcome the inter-lab variation in diet consumption and metal uptake in mice. These results increased the confidence of use of mouse bioassays in bioavailability studies.

Influence of culinary treatment on the concentration and on the bioavailability of cadmium, chromium, copper, and lead in seafood.

BACKGROUND: Seafood present important advantages for human nutrition, but it can also accumulate high levels of toxic and potentially toxic elements. Culinary treatments could influence seafood chemical element content and element bioavailability. In this study, the influence of culinary treatments on the total concentration and on the bioavailability of Cd, Cr, Cu and Pb in shark, shrimp, squid, oyster, and scallop was assessed. METHODS: Boiling, frying, and sautéing with or without seasonings (salt, lemon juice and garlic) were evaluated. Total concentration and bioavailability of Cd, Cr, Cu and Pb in seafood after all these culinary treatments were compared with those in uncooked samples. Analytes were determined by triple-quadrupole inductively coupled plasma mass spectrometry (ICP-MS/MS). An alternative to express the results avoiding underestimated or overestimated values was proposed. RESULTS: The analytes concentration in seafood without culinary treatment varied from 0.0030 µg g-1 (shrimp) to 0.338 µg g-1 (oyster) for Cd; 0.010 µg g-1 (squid) to 0.036 µg g-1 (oyster) for Cr; 0.088 µg g-1 (scallop) to 8.63 µg g-1 (oyster) for Cu, and < 0.005 µg g-1 (shrimp, squid and oyster) to 0.020 µg g-1 (shark) for Pb. Only Cd (in scallop) was influenced by culinary treatments (reduction from 37 to 53 % after boiling, frying, and sautéing). Bioavailability percentage varied from 11% (oyster) for Cd; 18% (oyster) to 41% (shark) for Cr; 6% (shark) for Cu, and 8% (oyster) for Pb. Bioavailability percentage was not influenced by culinary treatments. CONCLUSION: Cadmium concentration was reduced in scallop after some culinary treatments (reduction o 37-53% after boiling, frying, and sautéing), but bioavailability percentage was not influenced. The employed analytical method was adequate for the purpose, presenting import results for food safety assessment about the influence of culinary treatments on metals concentration and bioavailability in seafood.

Probabilistic pharmacokinetic modeling of airborne lead corresponding to toxicologically relevant blood lead levels in workers.

The Department of Defense (DOD) commissioned the National Research Council (NRC) to assess the potential health effects associated with exposure of DOD personnel to lead (Pb) at firing ranges. In that report, NRC concluded that the current Occupational Safety and Health Administration permissible exposure limit and the blood lead levels (BLLs) on which it was based were not sufficiently protective of worker populations covered under the general industry standard. In support of future selection of an occupational exposure limit, the relationship of airborne Pb levels to BLLs is of interest to the DOD. A subset of the BLLs identified as relevant to the management of health risks of exposed workers was selected as targets for extrapolation to equivalent airborne Pb values. The existing O'Flaherty physiologically based pharmacokinetic model for Pb in humans was modified to facilitate probabilistic predictions of DOD worker population BLLs, including 95th percentile values, based on current worker characteristics. Workplace airborne Pb 8-h time-weighted average concentrations of 1.1, 4.0, 6.8, or 9.8 µg/m3 are anticipated to maintain BLLs below 5, 10, 15, or 20 µg/dl, respectively, in the vast majority of DOD workers exposed to Pb under full-time working lifetime occupational exposure.

Lead exposure affects cephalic morphogenesis and neural crest cells in Gallus gallus embryo.

The morphogenesis of the head of vertebrates is a process that involves rapid growth and dynamic movements of various cell populations, including the neural crest cells (NCC). These pluripotent cells generated during neurulation have high proliferative and migratory capacity but xenobiotic agents can affect these migratory periods and cause congenital malformations. Lead (Pb) is the most common toxic metal in the environment and a potent teratogen that can affect growth and induce malformations. Despite the known toxic effects of Pb, there is a gap in knowledge about the impact of realistic concentrations of Pb at critical periods of early development. Here, we evaluated mortality, embryonic morphology, NCC migration, and the amount of Pb deposition in chicken embryos after 3 to 4 days of exposure. One of the most interesting observations in this study is that only about 34% of the injected Pb was present in the embryos after 4 days. We observed that exposure to Pb, even under low concentrations, increased mortality and the occurrence of malformations during embryonic development, especially in the cephalic region (CR). Although Pb was found widely distributed in the CR, no relation between its presence and the migration routes of cephalic NCC was observed. But the number of NCC and their migratory distance were reduced. These changes are consistent and explain the morphological anomalies described in this study, which also correlates with the morphofunctional abnormalities reported in the literature. Therefore, this study highlights the concern of exposure to low concentrations of this metal.

Prospective usage of magnesium potassium phosphate cement combined with Bougainvillea alba derived biochar to reduce Pb bioavailability in soil and its uptake by Spinacia oleracea L.

Combining biochar (BR) with other immobilizing amendments has additive effects on Pb immobilization and been recognized to be effective for the restoration of Pb polluted soils. However, the impacts of different proportions between BR and a highly efficient Pb immobilizing agent called "magnesium potassium phosphate cement (MC)" have never been earlier investigated. This work aimed to investigate the consequences of BR and MC alone and their mixtures of 25:75, 50:50, and 75:25 ratios on Pb bioavailability, Pb immobilization index (Pb-IMMi), and enzymatic activities in Pb polluted soil. Furthermore, amendments effects on Pb distribution in spinach, growth, antioxidant capacity, biochemical, and nutritional spectrum were also investigated. We found that MC alone performed well to immobilize Pb in soil and reducing its distribution in shoots, but was less efficient to improve soil enzymatic activities and plant attributes. Conversely, the application of BR alone stimulated soil enzymatic activities, plant growth, and quality but was less effective to immobilize Pb in soil and reducing shoot Pb concentrations. The combinations of BR and MC of various ratios showed variable results. Interestingly, the most promising outcomes were obtained with BR50%+MC50% treatment which resulted in enhanced Pb-IMMi (73%), activities of soil enzymes, plant growth and quality, and antioxidant capacity, compared to control. Likewise, significant reductions in Pb concentrations in shoots (85%), roots (78%), extractable Pb (73%) were also obtained with BR50%+MC50% treatment, compared to control. Such outcomes point towards a cost-effective approach for reducing Pb uptake by the plants via using MC and BR at a 50:50 ratio.

Contrasted tolerance of Agrostis capillaris metallicolous and non-metallicolous ecotypes in the context of a mining technosol amended by biochar, compost and iron sulfate.

Metal(loid) contamination of soil, resulting from the mining activities, is a major issue worldwide, due to its negative effects on the environment and health. Therefore, these contaminated soils need to be remediated. One realistic method is the assisted phytostabilization, which aims at establishing a vegetation cover on the soil that will reduce metal(loid) bioavailability and spreading through the prevention of wind erosion and water leaching. In addition, amendments are applied to improve soil conditions and ameliorate plant growth. In this goal, biochar and compost showed good results in terms of amelioration of soil fertility and reduction in lead bioavailability. However, they usually have a negative effect on arsenic. On the contrary, iron sulfate showed capacity to reduce arsenic mobility through interaction with its iron hydroxides. Finally, the choice of the appropriate plant species is crucial for the success of assisted phytostabilization. One good option is to use endemic species, adapted to the metal(loid) stress, with a fast growth and large shoot and root systems. The aims of this study were to (1) evaluate the effects of applying biochar, compost and iron sulfate, alone or combined, to a former mine soil on the soil properties and Agrostis capillaris growth, and (2) assess the difference between two Agrostis capillaris ecotypes, an endemic metallicolous ecotype and a non-metallicolous ecotype. Results of the mesocosm experiment showed that amendment application improved soil properties, i.e., reduced soil acidity, increased nutrient availability and lower metal(loid) stress, the best being the combination biochar-compost-iron sulfate. These ameliorations allowed a better plant growth. Finally, the metallicolous ecotype performed better in terms of growth than the non-metallicolous one and could thus be used in an assisted phytostabilization process on the former mine site.

Remediation by means of EDTA of an agricultural calcareous soil polluted with Pb.

The dispersion of mine tailings affects ecosystems due to their high content of potentially toxic elements. Environmental risk increases when the soil impacted by tailings is used for agriculture; this use may result in health impacts. This study analyzes the feasibility of remediating a calcareous soil (used for maize cultivation) polluted with lead in the semiarid zone of Zimapán, México, by using EDTA as an extractant. Total geoavailable and bioaccessible concentrations in the gastric and intestinal phases were determined to evaluate lead availability and health risk. The soil was then washed with EDTA, and the geochemical fractionation (interchangeable, carbonates, Fe/Mn oxy-hydroxides, organic matter-sulfides, and residual) and impact on the mesophile bacteria and fungi/yeast populations were analyzed. The results showed total Pb concentrations up to 647 ± 3.50 mg/kg, a 46% bioaccessible fraction (297 ± 9.90 mg/kg) in the gastric phase and a 12.2% (80 ± 5 mg/kg) bioaccessible fraction in the intestinal phase, indicating a health and environmental risk. Meanwhile, the geochemical fractionation before washing showed a Pb fraction mainly consisting of Fe/Mn oxy-hydroxides (69.6%); this reducible fraction may progressively increase its bioaccessibility. Geochemical fractionation performed in the washed soil showed differences from that determined before the treatment; however, the iron and manganese fraction, at 42.4%, accounted for most of the Pb. The soil microbiology was also modified by EDTA, with an increase in aerobic bacteria and a decrease in fungi/yeast populations. Although 44% total lead removal was achieved, corresponding to a final concentration of 363.50 ± 43.50 mg/kg (below national and USEPA standards), washing with EDTA increased the soluble and interchangeable lead concentrations. Statistical analysis indicated a significant effect (p < 0.05) of EDTA on the soil's geochemical fractionation of lead.

The migration of cadmium and lead in soil columns and their bioaccumulation in a multi-species soil system.

A soil microcosm experiment was carried out to quantify the transfer of cadmium (Cd) and lead (Pb) in a multi-species soil system (MS·3). Red earth from Jiangxi (S1), fluvo-aquic soil from Henan (S2), fluvo-aquic soil from Beijing (S3), and black soil from Heilongjiang (S4) were used for soil column packing with S1, S3, or S4 as the 20-50 cm layer and S2, which was Cd- and Pb-contaminated, as the top 0-20 cm layer. For each soil combination, four treatments were set up: CK (no wheat and no earthworm), W (only wheat), E (only earthworm), and E + W (earthworm and wheat). The results showed that the coexistence of earthworm with wheat reduced Cd and Pb contents in wheat plants and earthworms, and increased plant biomass, but had no significant effect on the survival rate and mean weight change rate of earthworms. Total Cd and Pb decreased remarkably in the 0-20 cm layer while increased in the 20-50 cm layer, and approximately 32.8%-51.1% of Cd and 0.35%-7.0% of Pb migrated down into the 20-50 cm soil layers from the 0-20 cm soil layers. The migration varied between the treatments from S2 to S1, S2, and S3. In S2-S1 and S2-S4 columns, the amount of Cd migration decreased when the earthworms coexisted with wheat, while in S2-S3 column, there was no significant difference on such amount regardless of the coexistence of earthworms with wheat. Taken together, the results indicated that the migration of Cd and Pb was not only associated with wheat and earthworm, but also depended on soil types.

A Clearance Period after Soluble Lead Nanoparticle Inhalation Did Not Ameliorate the Negative Effects on Target Tissues Due to Decreased Immune Response.

The inhalation of metal (including lead) nanoparticles poses a real health issue to people and animals living in polluted and/or industrial areas. In this study, we exposed mice to lead(II) nitrate nanoparticles [Pb(NO3)2 NPs], which represent a highly soluble form of lead, by inhalation. We aimed to uncover the effects of their exposure on individual target organs and to reveal potential variability in the lead clearance. We examined (i) lead biodistribution in target organs using laser ablation and inductively coupled plasma mass spectrometry (LA-ICP-MS) and atomic absorption spectrometry (AAS), (ii) lead effect on histopathological changes and immune cells response in secondary target organs and (iii) the clearance ability of target organs. In the lungs and liver, Pb(NO3)2 NP inhalation induced serious structural changes and their damage was present even after a 5-week clearance period despite the lead having been almost completely eliminated from the tissues. The numbers of macrophages significantly decreased after 11-week Pb(NO3)2 NP inhalation; conversely, abundance of alpha-smooth muscle actin (α-SMA)-positive cells, which are responsible for augmented collagen production, increased in both tissues. Moreover, the expression of nuclear factor κB (NF-κB) and selected cytokines, such as tumor necrosis factor alpha (TNFα), transforming growth factor beta 1 (TGFß1), interleukin 6(IL-6), IL-1α and IL-1ß , displayed a tissue-specific response to lead exposure. In summary, diminished inflammatory response in tissues after Pb(NO3)2 NPs inhalation was associated with prolonged negative effect of lead on tissues, as demonstrated by sustained pathological changes in target organs, even after long clearance period.

Lead (Pb) bioaccumulation and antioxidative responses in Tetraena qataranse.

Lead (Pb) is the second most toxic metal on Earth and is toxic to humans and other living things. In plants, Pb commonly inhibits growth when it is at a concentration in the soil of 30 mg/kg or more but several Pb tolerant plants have been reported. However, few studies have focused on plant response to Pb exposure, particularly at concentrations higher than 30 mg/kg. The assessment and evaluation of metal dose-dependent plant responses will assist in future phytoremediation studies. Therefore, this work documents the Pb concentration-dependent antioxidative response in Tetraena qataranse. Young seedlings were irrigated with 0, 25, 50, and 100 mg/L Pb every 48 h for seven weeks under greenhouse conditions. A phytotoxicity test showed that at the lowest treatment concentration, Pb stimulates growth. However, at 100 mg/L (1600 mg/kg Pb in the growth medium at harvest), the metal disrupted healthy growth in T. qataranse, particularly root development. Metal accumulation in the root was higher (up to 2784 mg/kg) than that of the shoot (1141.6 mg/kg). Activity assays of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), guaiacol peroxidase (GPX), and glutathione reductase (GR) showed a progressive increase in enzymatic activities due to Pb treatment. Together, the results of this study suggest that T. qataranse is a Pb hyperaccumulator. Increased antioxidant enzyme activity was essential to maintaining cellular homeostasis and assisted in the arid plant's tolerance to Pb stress.

Enzymatic and non-enzymatic detoxification in Lycosa terrestris and Pardosa birmanica exposed to single and binary mixture of copper and lead.

Organisms employ various enzymatic and non-enzymatic detoxification mechanisms to minimize the harmful effects of metal pollution in the terrestrial environment. We examined the effects of copper (Cu), lead (Pb) and their mixture (Cu + Pb) on glutathione (GSH), metallothionein (MTs), cytochrome P450 (CYP 450), carboxylesterase (CarbE), acetylcholinesterase (AchE) and glutathione S-transferase (GST) in Lycosa terrestris and Pardosa birmanica via two exposure routes, i.e., soil and food for 10, 20 and 40 days. The present results revealed that the accumulation of Cu and Pb in both spiders' species increase with exposure duration and depend on the route of exposure and type of metal. The activities of CarbE, GST, and MTs significantly increased with increasing metal body burden for all experimental treatments. The CYP 450 activity exhibited a significant time-dependent decrease with increasing Cu concentration in both species. The AchE activity was significantly inhibited on Pb exposure via soil and Cu + Pb exposure via both routes. The decrease in the level of GSH was measured on Cu + Pb exposure via both routes. Thus, all these enzymatic and non-enzymatic responses are sensitive to the metals tested and could serve as early warning indicators for assessing the effects of metal pollution in these species.

Tomato plants (Solanum lycopersicum L.) grown in experimental contaminated soil: Bioconcentration of potentially toxic elements and free radical scavenging evaluation.

Tomato is the most widespread vegetable crop in the world. In Italy, tomatoes are mainly cultivated in the South and in the Campania region, precisely in the area called Agro Nocerino-Sarnese. This flatland is affected by an extreme level of environmental degradation, especially related to the Sarno River, where concentrations of Potential Toxic Elements (PTEs) have been found to be higher than the maximum permitted level. The aim of this study was to determine the PTEs uptake by roots and their translocation to the aerial parts of the plants of two cultivars of tomatoes (Pomodoro Giallo and San Marzano Cirio 3). To the purpose, samples of the two cultivars were grown both in pots with experimentally contaminated soil containing: Cr or Cd or Pb at extremely high concentrations and in pots with uncontaminated soils (control). Additionally, the antioxidant properties of the cultivars selected grown on uncontaminated/contaminated soils were assessed. The results showed that Cd was the contaminant that most significantly interfered with the growth of both cultivars of tomato plants, whereas Pb caused lower phenotypical damage. Cd translocation from root to the organs of tomato plants was observed in both cultivars. Specifically, the total amount of Cd found in stems and leaves was higher in the Pomodoro Giallo (254.4 mg/kg dry weight) than in the San Marzano Cirio 3 (165.8 mg/kg dry weight). Cd was the only PTE found in the fruits of both cultivars, with values of 6.1 and 3.9 mg/kg dry weight of Pomodoro Giallo and San Marzano Cirio 3, respectively. The fruits of tomato plants grown in PTEs-contaminated soil showed inhibition or stimulations of the radical scavenging activity compared to the fruits grown in uncontaminated soil. This study highlighted that, despite the relatively high experimental concentrations of PTEs, their translocation to the edible part was comparatively low or absent.

Biochar effect on crop performance and Pb and Zn uptake of tomato (Solanum lycopersicum, L.) plants grown on heavy metals contaminated Kosovo soils.

A greenhouse pot experiment was conducted to evaluate the effect of biochar on the growth and uptake of Pb and Zn by tomato plants (Solanum lycopersicum, L.) cultivated in two highly contaminated Kosovo soils, A and B. Plants were cultivated in the biochar amended and unamended soils. As expected, the biochar addition to the two polluted soils has contributed to significantly improve the crop yields, in terms of both fresh and dry weight. Further, results indicated that the effect of biochar on metal mobility is closely related, besides its properties, to soil's native characteristics. In fact, the addition of biochar to soil B had also beneficial effects on the uptake of both metals, halving in some cases the values of the biological accumulation and transfer coefficients, while it did not show the same efficacy on soil A.

Toxic metal (Cd, Hg, Mn, Pb) partition in the maternal/foetal unit: A systematic mini - review of recent epidemiological studies.

The aim of this study was to summarise the available information regarding the partition of toxic metal (Cd, Hg, Mn, Pb) levels in the maternal/foetal unit from large epidemiological studies. We performed a systematic search of PubMed/MedLine, EMBASE, and ISI Web of Science for papers on Cd, total Hg, Mn or Pb levels in the maternal/cord blood that were published in English (n > = 200; 2010-2017). Data on year of publication, sample size, location, year of survey, and main results were extracted. We found a total of 35 papers. Most studies included large convenience samples of healthy pregnant women. The maternal/cord blood was properly used as a biomarker of prenatal exposure to toxic metals. The partition of these toxic metal levels in the maternal/foetal unit was metal-specific. Cd median levels (IQR) in cord blood reported worldwide were much lower [∼ 70 % < LOD = ± 0.11 µg/L] than those found in maternal blood [0.23 µg/L (0.15-0.35), ∼ 65 % > LOD]. Considering that Cd was under LOD in 70 % of the cord blood, Cd cord:maternal ratio as well as Cd cord proportion were not provided. Total Hg median levels (IQR) in cord blood [0.75 µg/L (0.40-1.19), ∼30 % < LOD = ±0.35 µg/L] were usually higher than in maternal blood [0.55 µg/L (0.40-0.85), ∼ 10 % < LOD = ±0.15 µg/L]. Hg cord:maternal ratio was 1.34 (1.00-1.91), and infants born would have Hg cord:(cord + maternal) proportion ranged from 0.50 to 0.63. Mn was the only metal that was detected in 100 % in both maternal (LOD : ±0.50 µg/L) and cord (LOD = ±0.2 µg/L) blood. Mn median levels (IQR) in cord blood [32.96 µg/L (26.90-40.10)] were 2 times higher than in maternal blood [14.01 µg/L (11.50-17.58)]. Mn cord:maternal ratio was 2.35 (1.09-3.80), and infants born would have Mn proportion ranged from 0.52 to 0.79. Pb median levels (IQR) in cord blood [5.79 µg/L (4.34-8.38), ∼ 5% < LOD : ±2.07 µg/L] were usually equal to or lower than those reported in maternal blood [8.07 µg/L (5.79-10.76), ∼ 1% < LOD = ±1.03 µg/L]. Pb cord:maternal ratio was 0.71 (0.59-0.96), and infants born would have Pb proportion ranged from 0.37 to 0.49. Globally, the results indicate that total Hg and Mn levels were lower in maternal blood but higher in cord blood. However, much greater variability was seen with Cd and Pb. At delivery, total Hg and Pb levels in maternal blood were strong predictors of cord blood levels. Our findings empty that understanding the partition, levels and correlations of toxic metals in the maternal/cord blood may help to elucidate the adverse effects of these metals on foetuses and neonates.

Effect of exposure to high temperatures in the excretion of cadmium and lead.

OBJECTIVE: This study aims to observe the effect on urine and sweat excretion levels of cadmium (Cd) and lead (Pb) in healthy men in a maximum incremental test until exhaustion and repeated exposure to heat. METHODS: twenty-nine adult men divided into control group (CG; n = 14) and experimental group (EG; n = 15) performing two maximum tests until exhaustion in normothermia (22 °C) and hyperthermia (42 °C). EG experienced 9 sessions of heat exposure at high temperatures (100 °C) (HEHT). After the nine sessions, the initial tests were repeated in both groups. Urine samples were collected before and after each test. After the hyperthermia tests, sweat samples were gathered. RESULTS: Urinary Cd increased after initial tests in GC and in hyperthermia in EG (p < 0.05). Urinary excretion of Pb rose after HEHT (p < 0.05). Pb in sweat was higher in EG than in CG after HEHT (p < 0.05). CONCLUSION: Heat exercise and constant exposure to heat can be a valid method to increase the excretion of toxic metals.