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Materials are needed to preferentially remove heavy metal pollutants from waste streams. Here, atomic scale simulation, based on density functional theory, is used to predict encapsulation energies and electronic structures of the one-dimensional yttrium silicide electride (Y5Si3:e–) hosting the heavy metals such as zinc (Zn), cadmium (Cd), mercury (Hg), chromium (Cr), nickel (Ni), copper (Cu), or lead (Pb). Assuming that the metals are present as dimers in gaseous waste, encapsulation is highly exoergic for those metals with incomplete p or d electrons (Cr, Ni, Cu, and Pb). Of the heavy metals with complete d shells (Zn, Cd, and Hg), only Zn exhibits strong encapsulation. Differences in encapsulation behavior are analyzed in terms of electronic structures, electron affinities, atomic radii, and Bader charges. [ABSTRACT FROM AUTHOR]

Our study aims to investigate the response of the unicellular alga, Haematococcus pluvialis, to the toxicity of lead and propose a low-cost, highly efficient biological adsorbent for the purification of wastewater and lead-contaminated water. The first part examines the effects of lead toxicity on certain physiological indicators of this alga. In the second part, the potential of this alga in lead removal and its adsorption capacity was assessed. The alga was cultivated in a BG11 medium and treated with lead nitrate concentrations of 10, 50, and 200 mg/L during its exponential growth. The results showed that with an increase in lead concentration up to 200 mg/L, the growth rate, chlorophyll a, chlorophyll b, carotenoid and total protein content decreased, while malondialdehyde (MDA) content increased. The astaxanthin content slightly increased at the 10 mg/L but decreased at the 200 mg/L treatment. Maximum lead adsorption was observed at 98.69% under optimal conditions, including a pH of 6, an adsorbent dose of 1 g/L, a lead concentration of 25 mg/L, a temperature of 25 °C, and an exposure time of 120 min. The results of this study demonstrate that Haematococcus pluvialis has the potential for effective lead removal from aquatic environments. While the influence of heavy metals on certain algae species has been explored, research on the impact of lead on Haematococcus pluvialis—a microalga of significant interest for astaxanthin production—remains uncharted territory. Therefore, understanding the impact of this heavy metal and the alga's metal absorption capabilities has profound implications for biotechnology and bioremediation applications. This study promotes H. pluvialis as an economically viable lead absorbent suitable for both industrial and domestic purposes. [ABSTRACT FROM AUTHOR]

Adsorption process plays an important role in the remediation of heavy metals (HMs) from wastewater. A laboratory trial was conducted to investigate effective parameters for improving the bio-adsorption removal of HMs. SEM, EDX, BET, and FTIR techniques were applied to characterize the calcined layer double hydroxide (Cal-LDH), pectin (PC), and Cal-LDH-PC composite prepared from Licorice pomace. The adsorption of zinc (Zn) cadmium, nickel (Ni) and lead (Pb) onto the most efficient sorbent was investigated using RSM methodology with operational factors such as concentration, reaction time, sorbent dose, and pH. The results related to FTIR showed that Cal-LDH-PC had the highest number of functional groups. Based on the SEM results Cal-LDH had a low surface area (9.36 m2 g-1) and a small pore size (9.22 nm). After the modification process (Cal-LDH-PC), the values of surface area and pore size increased by 13-fold (120 m2 g-1) and 1.5-fold (18 nm), respectively. Cal-LDH had high adsorption performance, more cavities, stability, various functional groups, and excessive carbon and oxygen content, which make it efficient and powerful in removing HMs from wastewater. The optimal condition for achieving the removal efficiency (RE%) values of metals was determined to be 80.79 mg L−1, 100 min, 0.167 g L−1, and 9 for concentration, reaction time, sorbent dose, and pH, respectively. Maximum adsorption capacity and RE (%) were 300 mg g−1 and 99% for Zn. According to the results concentration had a major impact on RE% (except for Ni), while for Ni, adsorbent dose had the most significant impact. The present study introduced Cal-LDH-PC prepared from Licorice pomace as a capable, useful and economical sorbent for HMs removal from polluted environments. Taguchi's statistical method is distinguished as an economic method with easier interpretation, while the RSM approach is more accurate, and it can also check the interaction of parameters. [ABSTRACT FROM AUTHOR]

In many countries with wastewater irrigation and intensive use of fertilizers (minerals and organics), heavy metal deposition by crops is regarded as a major environmental concern. A study was conducted to determine the impact of mineral fertilizers, cow manure, poultry manure, leaf litter, and sugarcane bagasse on soil's trace Pb content and edible parts of vegetables. It also evaluated the risk of lead (Pb) contamination in water, soil, and food crops. Six vegetables (Daucus carota, Brassica oleracea, Pisum sativum, Solanum tuberosum, Raphanus sativus, and Spinacia oleracea) were grown in the field under twelve treatments with different nutrient and water inputs. The lead concentrations in soil, vegetables for all treatments and water samples ranged from 1.038–10.478, 0.09346–9.0639 mg/kg and 0.036–0.26448 mg/L, The concentration of lead in soil treated with wastewater in treatment (T6) and vegetable samples was significantly higher, exceeding the WHO's permitted limit. Mineral and organic fertilizers combined with wastewater treatment reduced lead (Pb) concentrations in vegetables compared to wastewater application without organic fertilizers. Health risk indexes for all treatments except wastewater treatment (T6) were less than one. Pb concentrations in mineral fertilizers, cow manure, poultry manure, leaf litter, and sugarcane bagasse treated were determined to pose no possible risk to consumers. [ABSTRACT FROM AUTHOR]

Adsorption of heavy metals on stream sediments has important implications for the fate and transport of contaminants in subsurface ecosystems. Lead (Pb) is a potentially hazardous heavy metal that is found in high amounts in anthropogenic environments, especially aquatic ecosystems. The key mechanisms for distributing this metal in the environment are adsorption and desorption in stream to sediment, and vice versa. Therefore, this work is mainly focused on the study of the influence of amorphous Fe/Al-oxyhydroxides and soil organic matter (SOM) on the adsorption of Pb onto natural stream sediment. Spiking adsorption experiments were carried out with four types of samples namely, untreated dried sediment, Fe/Al-oxyhydroxides depleted sediment, SOM depleted sediment and both Fe/Al as well as SOM depleted sediment in the pH range of 3.0 to 8.0. The results showed that Pb adsorption was reduced by up to 45% in amorphous Fe/Al-oxyhydroxide depleted sediment at pH 4.0 to 6.0, whereas a similar adsorption reduction was observed in SOM depleted sediment at pH 6.5 to 7.5. Maximum Pb adsorption was reduced by up to 75% in both amorphous Fe/Al-oxyhydroxides and SOM depleted sediment samples at pH ranges ranging from 3.0 to 7.0. Furthermore, it was shown that SOM was most significant at pH 6.5, while Fe/Al-oxyhydroxides were more important when pH was > 6.5 for the Pb adsorption in natural stream sediment. [ABSTRACT FROM AUTHOR]

Lead (Pb) is one of the most toxic heavy metals (HMs) for plants and the environment. Sweetpotato [Ipomoea batatas (L.) Lam], the sixth most important food crop in the world, is tolerant to various environmental stresses, owing to its high antioxidant capacity. In this study, we selected sweetpotato cultivars showing high tolerance to lead (Pb) for phytoremediation-related applications. Young seedlings of 20 sweetpotato cultivars were treated with 30 mM Pb. Daeyumi (KO-12) and Dahomi (KO-5) were selected as Pb-tolerant and -sensitive cultivars, respectively, based on their photosynthetic activity and growth inhibition index (I50). In the Pb treatment, hydrogen peroxide and malondialdehyde contents of KO-12 were 1.5-fold less than those of KO-5. In addition, KO-12 showed a higher ability to accumulate Pb in roots and leaves than KO-5. Expression levels of four Pb-responsive genes, including the metallothionein gene IbMT1, were higher in the roots and leaves of KO-12 than in those of KO-5. Interestingly, KO-12 showed greater tolerance to high Pb concentrations than sunflower and rapeseed, which have been well-studied for phytoremediation. Our results suggest that sweetpotato is a suitable biomaterial for the phytoremediation of soils contaminated with HMs, including lead, for sustainable agriculture. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) and lead (Pb) concentrations were determined in samples of 31 species of vegetables (n = 719) and in vegetable products (n = 17), collected during the period January 2018 to September 2021. These originated from 33 countries, including Serbia. The samples were analysed by inductively coupled plasma – optical emission spectrometry (ICP-OES). Overall, Cd and Pb were found above the limit of detection in 123 (16.7%, n = 736) and 90 (12.2%; n = 736) samples, respectively. According to the former legislation, valid until the end of August 2021, the maximum levels (MLs) of Cd and Pb were exceeded in 1 and 2 samples of vegetables, respectively. Regarding the EU and Serbian legislation which is valid since September 2021 the MLs of Cd and Pb for vegetables were exceeded in 7 samples: Cd in 5 and Pb in 2 samples. In addition, 3 vegetable product samples exceeded the MLs for both cadmium and lead according to both former and current regulations. [ABSTRACT FROM AUTHOR]

The consumption of camel milk is gaining popularity in Algeria. This study aimed to determine the concentrations of Lead (Pb), Cadmium (Cd), Nickel (Ni) and Mercury (Hg) in camel milk sold in Southeast Algeria and assess the potential health risks associated with its consumption. 120 samples of camel milk were collected from 10 farms located near the roads in the south of Algeria. Metals were measured using an atomic absorption spectrophotometer with a graphite furnace and Target Hazard Quotients (THQs) were calculated. The mean concentrations were 0.026 ± 0.013 mg/kg, 0.001 ± 0.0002 mg/kg, 0.017 ± 0.002 mg/kg and 0.0005 ± 0.0002 mg/kg for Pb, Cd, Ni and Hg. The THQ was higher for children, suggesting health risks associated with consumption of camel milk for this age group (p <.001). The primary contribution of this study is the establishment of a database on toxic metal levels in camel milk, which can be valuable to manage possible risk associated with metals in milk. [ABSTRACT FROM AUTHOR]

Background: Biochar can enhance phytoremediation in petroleum hydrocarbon polluted soils, making it an intriguing soil amendment option for remediating polluted soil. Biochar can improve the fertility of depleted soils through a range of mechanisms. This study can contribute valuable insights into the origin of biochar and enhance our understanding of the efficacy of different biochar types in remediating petroleum hydrocarbon polluted soils. Aims: To assess the efficacy of different biochar types and plant growth in remediating petroleum hydrocarbon polluted soils. Methods: A field experiment was conducted at the automobile workshop (commonly called mechanic village) from July to October 2021, using a randomized complete block design. The land was sectioned into designated plots with three replicates. Maize stalk biochar (MSB) and nipa palm biochar (NPB) were treated differently in each plot at a rate of 20 t ha−1. Plots containing no biochar were used as controls. Initial and final soil analyses were conducted. Results: Preliminary soil assessments revealed higher values of soil bulk density (1.51 g cm−3), moisture content (35.02%), organic carbon (41.01 g kg−1), cation exchange capacity (13.27 cmol kg−1), total petroleum hydrocarbon content (PHCt) (775.83 mg kg−1), cadmium (Cd) (5.41 mg kg−1), chromium (Cr) (25 mg kg−1), lead (Pb) (33.51 mg kg−1), and zinc (Zn) (0.91 mg kg−1) in the polluted soil than in the unpolluted counterpart. The polluted soil displayed lower hydraulic conductivity (Ks) (1.17 cm h−1), available phosphorus (69.46 mg kg−1), manganese (Mn) (6.38 mg kg−1) and iron (Fe) (4.18 mg kg−1) contents than the unpolluted soil. The PHCt, Cd, and Cr were significantly decreased following the application of biochar. NPB recorded the lowest petroleum hydrocarbon (19%), lead (37%), manganese (57%), and zinc (69%) contents, whereas MSB had the lowest cadmium (50%) and chromium (27%) contents when compared with the control. Between heavy metal accumulations in the leaves and fruits, a greater accumulation of Cd, Cr, and Pb was found in the leaves, whereas Ni accumulation was found in the fruits. The highest Cd (47.0 mg kg−1) and Ni (8.3 mg kg−1) accumulations in the leaves were recorded in NPB treated plots. Similarly, Cd (5.3 mg kg−1), Cr (3.7 mg kg−1), Pb (21.6 mg kg−1), and Ni (23.4 mg kg−1) accumulation in the fruits recorded the highest values in the NPB treated plots. The NPB plants were the tallest compared with the other treatments. In addition, NPB plants had the widest leaf area compared with other treatments. Conclusion: The results indicated that the amendment of NPB may be suitable for the phytoremediation of soils polluted with petroleum hydrocarbons. [ABSTRACT FROM AUTHOR]

This paper reports the concentrations of uranium and heavy metals in drinking water samples from Garhwal Himalaya, India determined using LED Fluorimeter and Atomic Absorption Spectroscopy (AAS), respectively. The radiological (carcinogenic) and chemical (non-carcinogenic) risks associated with the consumption of uranium in water were estimated for the public. The concentrations of natural uranium in the analyzed drinking water samples vary from 0 to 21.57 ppb with a mean value of 1.54 ppb. The average concentrations of heavy metals in the analyzed drinking water samples were found to be in the order of iron (3.99 ppm) > zinc (0.32 ppm) > copper (0.04 ppm) > nickel (0.01 ppm) > chromium and lead (Below Detection Level). The estimated risk quantities were found to be lower than World Health Organization (WHO) and United State Environmental Protection Agency (USEPA) guideline values. [ABSTRACT FROM AUTHOR]

The demand for environment-friendly cleanup techniques has arisen due to an increase in environmental pollutants. Fungi is the most prevalent and effective class of heavy metal-resistant microorganisms with the ability to leach metals. The objective of the present study was to isolate the fungi from the agricultural soil of Kashmir valley, investigate their multi-metal tolerance to heavy metals and evaluate the metal uptake capacities of the resistant fungi. The fungi were isolated and identified on the basis of morphological and molecular approach (ITS1 and ITS4). The tolerance limits of the isolated fungal strains to various doses of lead (Pb), cadmium (Cd), zinc (Zn), chromium (Cr), copper (Cu), nickel (Ni), and cobalt (Co) was evaluated. Five fungal strains, Aspergillus niger, Fusarium oxysporum, Fusarium verticillioides, Aspergillus fischeri, Epicoccum mackenziei were isolated from the soil samples. To the best of our knowledge, this is the first report on the study of metal resistance of Aspergillus fischeri and Epicoccum mackenziei. Among the identified fungal species, Aspergillus niger and Fusarium oxysporum were found to be most tolerant with a minimum inhibitory concentration (MIC) of 600 ppm against Cu and Cr respectively. Results indicated removal of considerable amount of heavy metals by some of the fungi. The highest metal uptake of 8.31 mg/g was found in Fusarium verticillioides for Zn. Surprisingly, these fungal strains demonstrated resistance to metal concentrations above the levels that are universally acceptable for polluted soils, and hence prove to be appealing contenders for use as bioremediation agents for cleaning up heavy metal-polluted environments. [ABSTRACT FROM AUTHOR]

The present study aims to investigate the levels of some heavy metals: Arsenic (As), cadmium (Cd), lead (Pb) and mercury (Hg) in infused tea consumed in Riyadh, Saudi Arabia, and their potential health risk. Inductively coupled plasma mass spectrometry (ICP-MS) was used to assay the concentration of heavy metals in tea samples, after microwave acid digestion. This study was carried out on 25 brands of tea purchased from Riyadh city supermarkets. The validation of the proposed method was developed by measuring different parameters e.g. accuracy, precision, linearity, the lower limit of quantification (LLOQ), the lower limit of detection (LLOD). The method was examined for the determination of As, Cd, Pb and Hg in spiking samples with good accuracy and precision. The average daily intake (ADI), the hazard quotient (HQ), the total hazard quotations (THQs), and hazard index (HI) of the investigated metals were used for the assessment of health risks associated with the intake of metals. The mean concentration of heavy metals in infused tea were found in the range of 0.008–0.445, 0.0097–0.044, 0.012–2.379 and 0.0053–0.044 mg/kg for As, Cd, Pb and Hg, respectively. The results revealed that the concentration of As, Cd and Hg metals in all samples of infused tea was considered in the standard range, whereas the concentration of Pb exceeded the maximum concentration limit presented by World Health Organization (WHO). Therefore, the continuous monitoring of the concentration of heavy metals in tea is essential on a regular basis. [ABSTRACT FROM AUTHOR]

The efficacy of the lesser duckweed, Lemna aequinoctialis (Welw.), to remediate varying concentrations of cadmium, chromium, lead, and vanadium from an organo-metallic contaminated media was tested in artificial surface wetland mesocosm experiment. A 100 g of fresh-weight duckweed was introduced into each of the mesocosm, except for the control setup and monitored for 120 days while the metals removal rate was quantified using an atomic absorption spectrometer. A time-dependent and partial sorption of metals was observed with the highest removal rate recorded for cadmium (71.96%), followed by lead (69.23%), vanadium (55.22%), and chromium (41.64%). The uptake and bioaccumulation of metals were reflected in the increased plant biomass (p < 0.05, F = 97.12) and relative growth rate (p < 0.05, F = 1214.35) in duckweed. A coefficient (r2) of 0.951, 0.919, 0.970, and 0.967 was recorded for cadmium, chromium, lead, and vanadium respectively, indicating that the remediation of metals followed the first-order kinetic rate model. This study highlights the efficacy of the lesser duckweed to preferentially remediate metals in an organo-metallic complex medium for potential wastewater treatment in the petrochemical industry. Appling ecological or nature-based solutions for the treatment of complex wastewater from the petrochemical industry in Africa remains a challenge due to the paucity of evidence-based science to support the implementation that is acceptable to regulators and the industry. Although laboratory and field-based demonstration of phytoremediation studies has shown the potential of macrophytes for the treatment of organic and inorganic pollutants, studies on the application of duckweed for complex organo-metallic wastewater treatment for heavy metals are few. This study demonstrates the efficacy of the lesser duckweed, Lemna aequinoctialis in the sorption of cadmium, chromium, lead, and vanadium from an organo-metallic complex with potential application in the petrochemical industry. Oil spill releases hydrocarbons and associated metals into the environment. Hydrocarbons are degraded, but heavy metals remain in the environment. Lemna aequinoctialis demonstrated the partial sorption of metals in artificial wetlands. The phytoremediation of metal was time-dependent. The sorption rate fits into the first-order kinetic rate equation. [ABSTRACT FROM AUTHOR]

Objective: Accumulating evidence showed that exposure to heavy metals was harmful to human health. Little is known regarding the mixing effects of multiple metal exposures on vertebral compression fracture (VCF) and femoral neck bone mineral density (BMD). This study aimed to explore the individual and joint effects of four heavy metals [manganese (Mn), lead (Pb), cadmium (Cd) and mercury (Hg)] on VCF risk and femoral neck BMD. Methods: This cross-sectional study included 1,007 eligible individuals with vertebral fractures from National Health and Nutrition Examination Survey 2013–2014. The outcome was the risk of VCF and femoral neck BMD. Weighted multivariate logistic regression was used to explore the individual effect of four heavy metals on the VCF risk, separately. Weighted multivariate linear regression was used to explore the individual effect of four heavy metals on the femoral neck BMD, separately. Adopted bayesian kernel machine regression (BKMR) model and quantile-based g computation (qgcomp) to examine the joint effects of four heavy metals on the VCF risk and femoral neck BMD. Results: Among the population, 57 individuals developed VCF. After adjusting covariates, we found no statistical differences regarding the individual effects of four heavy metals on the risk of VCF. BKMR model and qgcomp indicated that there were no statistical differences regarding the joint effects between four heavy metals on the VCF risk. In addition, we found that Cd was associated with femoral neck BMD, and an increase in the mixture of heavy metal exposures was associated with a decreased risk of femoral neck BMD. Conclusion: No significant correlation was observed between co-exposure to Mn, Pb, Cd and Hg and VCF risk. But co-exposure to Mn, Pb, Cd and Hg may be associated with femoral neck BMD. [ABSTRACT FROM AUTHOR]

Background Study Design and Methods Results Conclusion Fetal and neonatal exposure to lead is associated with irreversible adverse effects on neural development. There is no reliable threshold for lead effect, so limiting exposure is recommended. A significant correlation has been reported between post‐transfusion blood lead level (BLL) in infants and lead levels in transfused RBC units. We measured levels of lead, mercury, and cadmium, in Canadian donor blood to investigate if concerning levels for neonatal transfusion exist.Whole blood samples from blood donors (n = 2529) were shipped cold within 7 days of donation. All permanent blood donation clinics across Canada were sampled. Twelve of these permanent clinics and 8 mobile clinics with a greater potential for having higher lead or mercury levels were oversampled. Heavy metals were measured by inductively coupled plasma mass spectrometry.Of all donations, 2.2% (lead) and 0.4% (mercury) had levels higher than the recommended thresholds for safe neonatal transfusion. BLLs were higher in males but there was no significant difference in the blood mercury levels of males versus females. Cadmium levels were higher in females. There was a positive correlation between donor age and levels of heavy metals, with lead having the strongest correlation (r = 0.47, p < .0001). Three clinics in close proximity to two lead‐producing mines were among the clinics with the highest BLLs. Significantly higher blood mercury levels were observed in coastal clinics.Our data on donor blood heavy metal levels supports considering blood transfusion as an exposure source to heavy metals and encourages informed selection of blood units for transfusion to vulnerable groups. [ABSTRACT FROM AUTHOR]

Nowadays, we have observed the dynamic development of bio-heating plants that use wood biomass for heating or energy purposes. The result of this process is a reduction in carbon dioxide emissions as well as in the production of biomass ash (BA). Despite the waste nature of BA, it should be carefully analyzed and assessed for various applications, including environmental ones. Due to the features attributed to BA, including its alkaline reaction, the high capacity of its sorption complex, relatively low salinity, and significant content of macro- and microelements, a hypothesis was put forward in this work undertaken about the positive role of BA as an immobilizing factor for Cd-, Pb-, and Zn-contaminated soils. This research was based on a pot experiment in which four series were considered: (1) BA; (2) BA + Cd; (3) BA + Pb; and (4) BA + Zn. BA was used at doses of 30, 60, and 90 mg pot−1, and metals at doses of 2 mg Cd, 100 mg Pb, and 300 mg Zn kg−1 of soil. The test plant was corn grown for green mass. The study took into account the influence of BA on the content of the total forms of heavy metals (Metot) and their available forms (Meav). In the soil without the addition of metals, a significant increase in the content of Cdtot and Cdav, and a decrease in the content of Zntot were observed due to the application of BA. The addition of metals against the background of the BA used resulted in a significant increase in Cdtot, Pbtot, and Zntot, as well as an increase in the available forms of Pbav but a decrease in Znav. However, there was no significant increase in the Cdav content. The obtained results may indicate the potentially immobilizing role of BA only in the case of zinc. They may constitute the basis for further, more detailed research aimed at determining the role of BA in the immobilization of various metals in soil. [ABSTRACT FROM AUTHOR]

The objective of this study is to develop a remediation technology for composited heavy metal-contaminated soil. Biochars (BC300, BC400, and BC500) derived from corn were combined with potassium dihydrogen phosphate (KH2PO4) to immobilize and remove heavy metal ions, including mercury (Hg2+), cadmium (Cd2+), and lead (Pb2+). The adsorption kinetics of metal ions in aqueous solutions with different concentrations was tested, and the fitting effects of the two models were compared. The findings demonstrate that the joint application of biochar and KH2PO4 could markedly enhance the immobilization efficacy of Pb2+, whereas the utilization of KH2PO4 on its own exhibited a more pronounced immobilization impact on Cd2+. Furthermore, the present study underscores the shortcomings of various remediation techniques that must be taken into account when addressing heavy metal-contaminated soils. It also emphasizes the value of comprehensive remediation techniques that integrate multiple remediation agents. This study offers a novel approach and methodology for addressing the intricate and evolving challenges posed by heavy metal contamination in soil. Its practical value and potential for application are significant. [ABSTRACT FROM AUTHOR]

Heavy metal subdwarfs are a class of hot subdwarfs with very high abundances of heavy elements, typically around 10 000 times solar. They include stars, which are strongly enhanced in either lead or zirconium, as well as other elements. Vertical stratification of the enhanced elements, where the element is concentrated in a thin layer of the atmosphere, has been proposed as a mechanism to explain the apparent high abundances. This paper explores the effects of the vertical stratification of lead on the theoretical spectra of hot subdwarfs. The concentration of lead in different regions of the model atmosphere is found to affect individual lines in a broadly wavelength-dependent manner, with the potential for lines to display modified profiles depending on the location of lead enhancement in the atmosphere. This wavelength dependence highlights the importance of observations in both the optical and the UV for determining whether stratification is present in real stars. [ABSTRACT FROM AUTHOR]

One of the major concerns worldwide is the rapid increase in water pollution with hazardous heavy metals. The Cucurbit[n]uril (CB[n]) structure provides an inner hydrophobic cavity accessible through two electrostatically negative portals with polar carbonyl groups, allowing for charged ion–dipole interaction between cationic species with excellent binding affinities. In this work we selected CB[5], and CB[7] for the titrimetric and electrochemical evaluation of the heavy metal complexes formed with Copper(II), Cadmium(II) and Lead(II). The host–guest interaction was found by either attenuation of the redox peaks, the formation of a new peak, or the slight shift in the redox peaks of the heavy metal ions. Titration data were obtained for CB[n] with the heavy metal solutions to determine the molar coefficient of binding. The stoichiometry of the complexes was 1 : 1 by Job′s plot. We calculated the binding constants using the Benesi–Hildebrand method achieving relatively good binding constants (K) ranging from (1.80±0.14)×105–(4.98±0.13)×105 M−1. The results showed that the complexes of Cadmium(II) and Lead(II) with both CB[5] and CB[7] are highly stable in aqueous media. Copper(II) was able to bind to the smaller sized portal of CB[5], whereas with CB[7] the heavy metal ion could not form a favourable complex. This phenomenon suggests that the CB[5] is an ideal host at forming stable host–guest interactions than their larger homologue. [ABSTRACT FROM AUTHOR]

Heavy metals are one of the most dangerous environmental pollutions, and their elimination is one of the health system's priorities. Microorganisms have been introduced as a safe absorber of such pollution and this ability is related to the characteristics of their surface layers. There are reports about some bacteria's increment of cell envelope thickness in space conditions. Therefore, this study investigated SMG effect on heavy metals biosorption using Saccharomyces (S.) cerevisiae. Furthermore, the stability of complex, isotherm, and kinetic absorption models has been investigated. The results showed that the SMG positively affected the biosorption of mercury (Hg) 97% and lead (Pb) 72.5% by S. cerevisiae. In contrast, it did not affect cadmium (Cd) and arsenic (As) biosorption. In gastrointestinal conditions, Hg, Cd, and As‐yeast complexes were stable, and their biosorption increased. In the case of the Pb‐yeast complex, in simulated gastric exposure, the binding decreased at first but increased again in simulated intestinal exposure in both SMG and normal gravity (NG). The metals' biosorption by yeast followed the pseudo‐second‐order kinetic and the Langmuir isotherm models for all metals (As) matched with Langmuir and Freundlich. The current research results demonstrate that microgravity provides desirable conditions for heavy metal biosorption by S. cerevisiae. Furthermore, the biosorbent–heavy metal complex remains stable after simulated gastrointestinal conditions. Altogether, the results of this study could be considered in detoxifying food and beverage industries and maintaining astronauts' health. [ABSTRACT FROM AUTHOR]

The presence of heavy metals such as arsenic, cobalt, cadmium, lead and mercury in canned food is of great importance from the point of view of their toxicity and nature, and it covers a wide range of food. The presence of these metals in canned products is sometimes the source of the food, the type of can or the possibility of corrosion of the inner body of the used can is attributed. Therefore, the purpose of this study was to measure and compare the concentration of heavy metals in canned food (strong acid, acid, low acid). In order to analyze the data, descriptive statistics methods were used to compare the mean and difference between the data, the one -way multivariate variance measurement and the Kolmogorov -Smirnov test were used to ensure the normality of the data and if there was a significant difference between the data, then Tukey's test was performed to separate the data. The results of this research showed that the average concentration of heavy metals was in the order of lead > mercury > cobalt > arsenic > cadmium, and among the available metals, lead with a total average of 0.2670 ± 0.019723 mg/ kg had the highest value and cadmium had the lowest value with an average of 0.0028±0.0049. Compared to international standards and other studies, all metals except lead were lower than the maximum value. Although the concentration of these metals in canned food samples was acceptable but it is necessary to pay attention to the factors that increase the presence of these metals in canned goods in order to control them and achieve a high -quality product . [ABSTRACT FROM AUTHOR]

The use of probiotic lactobacilli has been proposed as a strategy to mitigate damage associated with exposure to toxic metals. Their protective effect against cationic metal ions, such as those of mercury or lead, is believed to stem from their chelating and accumulating potential. However, their retention of anionic toxic metalloids, such as inorganic arsenic, is generally low. Through the construction of mutants in phosphate transporter genes (pst) in Lactiplantibacillus plantarum and Lacticaseibacillus paracasei strains, coupled with arsenate [As(V)] uptake and toxicity assays, we determined that the incorporation of As(V), which structurally resembles phosphate, is likely facilitated by phosphate transporters. Surprisingly, inactivation in Lc. paracasei of PhoP, the transcriptional regulator of the two-component system PhoPR, a signal transducer involved in phosphate sensing, led to an increased resistance to arsenite [As(III)]. In comparison to the wild type, the phoP strain exhibited no differences in the ability to retain As(III), and there were no observed changes in the oxidation of As(III) to the less toxic As(V). These results reinforce the idea that specific transport, and not unspecific cell retention, plays a role in As(V) biosorption by lactobacilli, while they reveal an unexpected phenotype for the lack of the pleiotropic regulator PhoP. [ABSTRACT FROM AUTHOR]

Investigating the presence of microplastics in the Pasig River, the highest plastic-emitting river in the Philippines and one of the ocean's leading contributors of these materials, is highly relevant. In this study, surficial sediments in eight stations along the main channel of the Pasig River were analyzed for microplastic content, heavy metals, and soil texture. The microplastics were categorized according to shape, color, and size. The polymer type was determined using infrared spectroscopy. The number of microplastics was correlated with heavy metals, soil texture, and flow velocity. The results show that the dominant shape, color, size, and polymer type were fragment, color white, size range from 0 to 500 μm, and polyvinyl alcohol, respectively. Downstream stations 5 and 8 had the highest microplastic concentration. The number of microplastics showed a positive moderate correlation with percent sand (r = 0.40) and clay (r = 0.42), and a negative high correlation with percent silt (r=-0.80). For microplastics and heavy metals, a positive moderate correlation was observed for iron (r = 0.52) and zinc (r = 0.58), while a negative weak correlation was present for lead (r=-0.06). Microplastics and flow velocity showed weak correlations demonstrating that the accumulation in the bottom river sediment may be based on the proximity of the plastic source rather than on the flowing water with plastic sources. Results reflect the diverse influences on the Pasig River which is surrounded by informal settlements, manufacturing industries, urban offices, and residential areas. More plastic management initiatives and better implementation of existing laws should be done by the government. [ABSTRACT FROM AUTHOR]

In this study, eco-friendly casein-copper hybrid nanoflowers (CAS-Cu HNFs) were synthesised and their applicability for the removal of Pb(II) and Cd(II) ions was investigated. Hybrid nanoflowers were synthesised by adding CuSO4 solution on casein in PBS medium. According to the evaluation of SEM images, regular nanoflower structures were obtained after the addition of 40 µL of 100 mM CuSO4 and 12 h incubation. Characterisation studies were performed by XRD, SEM-EDX, FTIR and TGA. The effects of contact time, pH, temperature and heavy metal ion concentration on the adsorption performance were investigated. Optimum adsorption was achieved at 60 min contact time and 35 and 30 °C for Pb(II) and Cd(II) ions, respectively. The performance of CAS-Cu HNFs was evaluated by linear and non-linear forms of adsorption isotherms and adsorption kinetics, respectively. The linear Langmuir isotherm model showed compatibility and the maximum adsorption capacity was found to be 769.23 and 156.25 mg/g for Pb(II) and Cd(II) ions, respectively. CAS-Cu HNFs has great potential as an eco-friendly, nanoscale, flower-like, organic–inorganic hybrid nano-flower adsorbent for the effective removal of Pb(II) and Cd(II) ions from aqueous solutions. [ABSTRACT FROM AUTHOR]

Kawasaki disease (KD) is an acute systemic vasculitis primarily affecting young children, with an unclear etiology. We investigated the link between maternal heavy metal exposure and KD incidence in children using the Japan Environment and Children's Study, a large-scale nationwide prospective cohort with approximately 100,000 mother–child pairs. Maternal blood samples collected during the second/third trimester were analyzed for heavy metals [mercury (Hg), cadmium (Cd), lead (Pb), selenium (Se), manganese (Mn)], divided into four quartiles based on concentration levels. KD incidence within the first year of life was tracked via questionnaire. Among 85,378 mother–child pairs, 316 children (0.37%) under one year were diagnosed with KD. Compared with the lowest concentration group (Q1), the highest (Q4) showed odds ratios (95% confidence interval) for Hg, 1.29 (0.82–2.03); Cd, 0.99 (0.63–1.58); Pb, 0.84 (0.52–1.34); Se, 1.17 (0.70–1.94); Mn, 0.70 (0.44–1.11), indicating no concentration-dependent increase. Sensitivity analyses with logarithmic transformation and extended outcomes up to age 3 yielded similar results. No significant association was found between maternal heavy metal levels and KD incidence, suggesting that heavy metal exposure does not increase KD risk. [ABSTRACT FROM AUTHOR]

Land transportation is a major source of heavy metal contamination along the roadside, posing significant risks to human health through inhalation, oral ingestion, and dermal contact. Therefore, this study has been designed to determine the concentrations of vehicular released heavy metals (Cd, Pb, Ni, and Cu) in roadside soil and leaves of two commonly growing native plant species (Calotropis procera and Nerium oleander).Two busy roads i.e., Lahore-Okara road (N-5) and Okara-Faisalabad roads (OFR) in Punjab, Pakistan, were selected for the study. The data were collected from five sites along each road during four seasons. Control samples were collected ~ 50 m away from road. The metal content i.e. lead (Pb), cadmium (Cd) nickel (Ni) and copper (Cu) were determined in the plant leaves and soil by using Atomic Absorption Spectrophotometer (AAS). Significantly high amount of all studied heavy metals were observed in soil and plant leaves along both roads in contrast to control ones. The mean concentration of metals in soil ranged as Cd (2.20–6.83 mg/kg), Pb (4.53–15.29 mg/kg), Ni (29.78–101.26 mg/kg), and Cu (61.68–138.46 mg/kg) and in plant leaves Cd (0.093–0.53 mg/kg), Pb (4.31–16.34 mg/kg), Ni (4.13–16.34 mg/kg) and Cu (2.98–32.74 mg/kg). Among roads, higher metal contamination was noted along N-5 road. Significant temporal variations were also noted in metal contamination along both roads. The order of metal contamination in soil and plant leaves in different seasons was summer > autumn > spring > winter. Furthermore, the metal accumulation potential of Calotropis procera was higher than that of Nerium oleander. Therefore, for sustainable management of metal contamination, the plantation of Calotropis procera is recommended along roadsides. [ABSTRACT FROM AUTHOR]

Due to the rising concern about heavy metals in settled dust, a risk assessment of Arsenic (As), Cadmium (Cd), Copper (Cu), Lead (Pb), Nickel (Ni) and Zinc (Zn) has been conducted using multiple exposure paths, including oral ingestion, direct skin contact, and inhalation of dust around lake Urmia in Iran for the time period of 2020. Metal concentrations were assessed and sources were identified based on the enrichment factor and Pearson correlation coefficient. The metal concentrations were in the following order: Zn > Cu > Ni > Pb > Cd > As with arithmetic means of 3.5, 4.8, 57, 33, 25 and 83 mg/kg, respectively, which are within the range of Iran-EPA soil guideline values. A very weak correlation (r < 0.7) was found between the studied elements. The average enrichment factor (EF) for As, Cd, Cu, Ni, Pb, and Zn was 0.7, 4, 1.8, 0.5, 3.2 and 0.8, respectively, suggests minor enrichment for metals and influence from anthropogenic activity. The lifetime cancer risks (LTCR) due to exposure (three routes of inhalation) to metals were in the negligible risk category. The oral route had the highest hazard index (HI) between all of exposure paths. The HI was less than 1 for all three exposure paths. Moreover, the sensitivity analysis showed that exposure duration (ED) for As and Ni and exposure frequency (EF) for Cd and Pb had the highest impacts on LTCR values. Therefore, this study suggests the continuous monitoring of heavy metals in settled dust around the Lake Urmia as it is associated with the high health risk for the neighbourhood in the Lake Urmia's basin. [ABSTRACT FROM AUTHOR]

Schiff bases (SBs) are important ligands in coordination chemistry due to their unique structural properties. Their ability to form complexes with metal ions has been exploited for the environmental detection of emerging water contaminants. In this work, we evaluated the complexation ability of three newly proposed SBs, 1–3, by complete conformational analysis, using a combination of Molecular Dynamics and Density Functional Theory studies, to understand their ability to coordinate toxic heavy metal (HMs) ions. From this study, it emerges that all the ligands present geometries that make them suitable to complex HMs through the N-imino moieties or, in the case of 3, with the support of the oxygen atoms of the ethylene diether chain. In particular, this ligand shows the most promising coordination behavior, particularly with Pb2+. [ABSTRACT FROM AUTHOR]

Understanding heavy metals in rivers is crucial, as their presence and distribution impact water quality, ecosystem health, and human well-being. This study examined the presence and levels of nine heavy metals (Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, and Zn) in 16 surface water samples along the Chao Phraya River, identifying Fe, Mn, Zn, and Cr as predominant metals. Although average concentrations in both rainy and dry seasons generally adhered to WHO guidelines, Mn exceeded these limits yet remained within Thailand's acceptable standards. Seasonal variations were observed in the Chao Phraya River, and Spearman's correlation coefficient analysis established significant associations between season and concentrations of heavy metals. The water quality index (WQI) demonstrated varied water quality statuses at each sampling point along the Chao Phraya River, indicating poor conditions during the rainy season, further deteriorating to very poor conditions in the dry season. The hazard potential index (HPI) was employed to assess heavy metal contamination, revealing that during the dry season in the estuary area, the HPI value exceeded the critical threshold index, indicating the presence of heavy metal pollution in the water and unsuitable for consumption. Using the species sensitivity distribution model, an ecological risk assessment ranked the heavy metals' HC5 values as Pb > Zn > Cr > Cu > Hg > Cd > Ni, identifying nickel as the most detrimental and lead as the least toxic. Despite Cr and Zn showing a moderate risk, and Cu and Ni posing a high risk to aquatic organisms, the main contributors to ecological risk were identified as Cu, Ni, and Zn, suggesting a significant potential ecological risk in the Chao Phraya River's surface water. The results of this study provide fundamental insights that can direct future actions in preventing and managing heavy metal pollution in the river ecosystem. [ABSTRACT FROM AUTHOR]

Macroalgae are considered a valuable source of several compounds with nutritional, nutraceutical, cosmeceutical, and pharmaceutical applications. They are also used for crop fertilization and biofortification by introducing important minerals into the soil essential for crop productivity. At the same time, however, they are known bio-accumulators of some heavy metals. In this work, we assessed the content of 7 minerals considered as heavy metals in 25 macroalgae samples, comprising 4 greens, 9 reds and 12 browns, from Madeira Archipelago, Portugal, for their potential use as blue bioeconomy products. These heavy metals included zinc (Zn) with concentrations that ranged from 1.95 – 242.65 mg kg−1 dw, nickel (Ni, 0.6 – 34.78 mg kg−1 dw), copper (Cu, 0.42 – 7.98 mg kg−1 dw), chromium (Cr, 0.47 – 45.74 mg kg−1 dw), cadmium (Cd, 0.1 – 2.58 mg kg−1 dw), lead (Pb, 0.05 – 2.79 mg kg−1 dw) and mercury (Hg, 0.03 – 8.49 µg kg−1 dw). We also analysed 22 samples of beach-cast macroalgae from Gran Canaria Island, Spain, collected from November 2016 to November 2019. The same heavy metals were assessed with their concentrations that ranged as follows: Zn (11.41 – 42.20 mg kg−1 dw), Ni (3.17 – 17.78 mg kg−1 dw), Cu (1.85 – 4.20 mg kg−1 dw), Cr (6.08 – 37.98 mg kg−1 dw), Cd (0.02 – 0.11 g kg−1 dw), Pb (0.16 –5.42 mg kg−1 dw) and Hg (3.59 – 31.00 µg kg−1 dw). These concentrations are all within the normal ranges reported in earlier studies in low industrialized areas, except for the brown algae Gongolaria abies-marina and Sargassum vulgare with high mean (± SD) Cd concentration (1.91 ± 0.36 and 1.75 ± 0.07 g kg−1 dw respectively). Our results suggest that most of the biomass prospected in these localities covered in the present study would be a viable source of materials for the development of a blue economy industry with emerging products following the European Union directives. [ABSTRACT FROM AUTHOR]

Background and Objectives: Previous studies have shown an association between environmental exposure to heavy metals and hearing loss. However, the findings regarding the relationship between exposure to different metals and hearing loss development are inconsistent. To address this, we conducted a meta‐analysis to explore the link between common heavy metal exposures and hearing loss. This study examined the effects of lead (Pb), cadmium (Cd), and mercury (Hg) pollution on hearing loss at various levels, and systematically reviewed the literature on manganese (Mn), barium (Ba), arsenic (As), and hearing loss. Methods: We conducted systematic searches in five major databases, including PubMed, Web of Science, Embase, Cochrane Library, and Scopus. In addition, we searched three Chinese digital libraries: CNKI, Wanfang Data, and Wipu. From an initial pool of 649 articles, we carefully screened and selected 15 articles for further analysis. The effect sizes from these selected studies were synthesized through a meta‐analysis to calculate the overall effect size. Results: Our findings showed that: (1) There was a significant association between Pb and Cd exposure and hearing loss; (2) There is a proportional relationship between the increase of metal index detected in blood and hearing loss; (3) In the PTA measurement of hearing loss at different frequencies, the 4 kHz high frequency range had a stronger correlation with hearing loss than the low frequency, with OR 1.44 (1.22, 1.71); and (4) There was a more significant correlation between Barium (Ba) levels in nails and hair than in urine. Conclusions: The study presented evidence of a significant association between human hearing loss and exposure to lead (Pb) and cadmium (Cd). It not only revealed a positive correlation between blood heavy metal concentrations and the incidence of hearing loss but also highlighted that long‐term exposure indicators of heavy metals were more indicative of the correlation with hearing loss. Lastly, the study recommends utilizing high frequency 4 kHz for the effective assessment and diagnosis of hearing loss caused by exposure to heavy metals. [ABSTRACT FROM AUTHOR]

Conventional electroless Ni–B–Mo (ENB–Mo) deposits are formed using hazardous lead or thallium-containing solutions, which must be removed. In this study, ENB–Mo deposits were developed in a bath free of stabilizers and harmful heavy metals. This study estimates the effect of variation of coating bath temperature on tribological performance of ENB–Mo coating developed over AISI 1040 steel. The chosen bath temperatures were 8 5 ∘ C, 9 0 ∘ C, and 9 5 ∘ C to achieve ENB–Mo coating with varying B and Mo content. The 12–15 μ m thick coating was uniform. In comparison to steel substrate, all of the coatings show enhanced corrosion resistance. In the as-deposited state, coatings were mixed amorphous and nanocrystalline with peak of Fe overlapping with Ni. Moreover, TGA results revealed that inclusion of molybdenum enhanced coatings thermal stability. The worn specimens at 3 0 0 ∘ C reveal development of shielding tribo-oxide coatings and existence of microstructural changes. At high working temperatures (3 0 0 ∘ C), wear debris also has a major impact on tribological mechanisms of coatings. Correlation between microstructure, tribological behavior, and corrosion resistance have also been conducted for ENB–Mo coatings. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to systematically review the health risk assessment of the concentration of heavy metals in Pistacia species globally. Design/methodology/approach: The authors systematically searched PubMed, Science Direct, Scopus and Google Scholar to identify all articles published between 1 January 2002 and 20 August 2022. A total of 33 studies met the authors' inclusion criteria, and their data were extracted. Additionally, the potential risk to human health was assessed by calculating the target hazard quotient and hazard index for both child and adult consumers. Findings: The estimated daily intake for heavy metals in the included studies ranged from 9.72 × 10–9 to 7.35 (mg/day) in the following order: zinc (Zn) > mercury (Hg) > iron (Fe) > lead (Pb) > copper (Cu) > aluminum (Al) > nickel (Ni) > chromium (Cr) > manganese (Mn) > cadmium (Cd) > arsenic (As) > selenium (Se) > cobalt (Co). Among the studies that investigated heavy metals in Pistacia species around the world, the non-carcinogenic risk for all species of Pistacia was determined to be less than 1, except for Pb and Hg in Pistacia lentiscus. Originality/value: The soil near the industrial area contained excessive amounts of heavy metals, which led to the transfer of heavy metals to plants. Owing to the insufficiency of the number of studies that examined heavy metals in Pistacia species, further monitoring and investigations were recommended. [ABSTRACT FROM AUTHOR]

Regular monitoring of the water quality and heavy metal concentration in edible fish from the Pulangi Lake - an artificial lake in Bukidnon, the Philippines - has not yet been established. This study analyzed the water quality of the Pulangi Lake and assessed the associated risks of heavy metals cadmium (Cd), chromium (Cr), and lead (Pb) in Nile tilapia (Oreochromis niloticus) harvested from the lake during the dry season. Key informant interviews (KII) were also conducted to gather relevant information about the lake. The physico-chemical analysis of the surface water revealed high fecal coliform levels, exceeding the standard limit by more than 100%, but the concentrations of Cd, Cr, and Pb were below the standard limit. However, the Cr concentration in tilapia (0.2430-1.7870 mg/kg) exceeded the permissible limit of 0.05 mg/kg set by the Food and Agriculture Organization and the World Health Organization. Low concentrations of Cd (0.0270-0.1140 mg/kg) and Pb (0.0360-0.4350 mg/kg) were observed. The risk assessment of these individual heavy metals measured from tilapia and its combined impacts showed no potential non-carcinogenic effects based on the estimated target hazard quotient (THQ < 1) and hazard index (HI < 1). However, based on the permissible target cancer risk (1 x 10-6 to 1 x 10-4), tilapia from the Pulangi Lake should be reexamined as it appears that - in terms of Cd and Cr - the probability relating to contamination problem can occur. The present study can be used as baseline data for risk management. [ABSTRACT FROM AUTHOR]

In this study, the wastewater analyses of Oued K'sob for one year showed a spatiotemporal diminution of zinc content seasonally, it rest light than copper. But Zinc and copper a threat to the environment of the region. The wastewater analyses of Oued K'sob water for one year showed a spatiotemporal diminution of zinc content seasonally, with a minimum and maximum range of 249 ± 219 µg/l and 2382 ± 3426 µg/l obtained in autumn and summer for the zinc and 75 ± 24 µg/l and 433 ± 310 µg/l obtained in winter and spring at the first and fifth station for the copper. These concentrations of zinc and copper a threat to the environment of the region. Like a solution for this problem, the absorption, accumulation and translocation abilities of Phragmites australis were determined toward iron (Fe), copper (Cu), zinc (Zn) and lead (Pb). In the soils contaminated by different concentrations (100, 200 and 500 mg/L), the absorption, accumulation and transport ability of elements were evaluated via the Bio-concentration (BCF), Bioaccumulation (BF) and Translocation (TF) factors. A proportional increase between the BCF, BFs, TFs and the irrigation concentrations, where BCFs of all metallic elements exceed 1 and the Zn BCF, BFs and TFL are the highest and exceed 1 relative to the other elements which remain lower than 1, which has a low accumulation. Therefore, according to the BCFs obtained and which exceed 1, we can consider this plant as a hyper-accumulator of Zn, Fe, Cu and Pb. Extraction of fatty and organic acids followed by HPLC confirmed the oxalic, citric, malic, succinic, fumaric, formic, acetic, propionic, and butyric acid presence, which are responsible for the transport of the metal from roots to leaves. In the light of these results, we can therefore propose Phragmites australis species as an alternative and natural solution to reduce the high concentrations of zinc and copper in the Oued k'sob (region of Bordj Bou Arreridj, Algeria). The main objective of this study was to carry out and determine the phyto-remedial effect of Phragmites australis species in pots from artificial contaminated soils in order to classify this plant as an accumulator or hyper-accumulator of metals, in particular against zinc, iron, copper and lead in order to reduce their toxicities in the environment through decontamination and/or protection of the ecosystems (soil and water); and why not use this bioremediation system via this species during wastewater treatment at wastewater treatment plants to increase the quality of treatment of one side and reduce the cost on the other side. [ABSTRACT FROM AUTHOR]

Hyperspectral remote sensing technology is an advanced and powerful tool that enables fine identification of the numerous soil reflectance spectrum characteristics. Heavy metal(loid)s (HMs) are the primary pollutants affecting the soil biodiversity and ecosystem services. Estimating HMs' concentrations in soils using hyperspectral data is an effective method but is challenging due to the effects of varied soil properties and measurement-related errors inflicted by atmospheric effects. This study focused on typical mining areas in the Fenwei Plain (FWP), China. Soil-related data were collected by leveraging airborne- and ground-based integrated remote sensing observations. The concentrations of eight HMs, namely copper (Cu), lead (Pb), zinc (Zn), nickel (Ni), chromium (Cr), cadmium (Cd), arsenic (As), and mercury (Hg), were measured by laboratory analysis from 100 in situ soil samples. Soil reflectance spectra were processed based on resampling and envelope methods. The combination datasets of the concentrations and optimal soil reflectance spectra were used to build the soil-related parameter retrieval models using three machine learning (ML) methods, and the feasibility of applying the high-performance retrieval model to estimate the HM concentrations in mining areas was evaluated and explored. Spectral analysis results show that four hundred and twenty-eight bands of five wavelength ranges are of high quality and obviously demonstrate the spectral characteristics selected to build the soil-related parameter models. The evaluation results of eight combination data subsets and three methods show that the preprocessing of spectral data (ground- and airborne-based reflectance) and soil samples with the random forest (RF) method can obtain higher accuracy than support vector machine (SVM) and partial least squares (PLS) methods, denoted as the AER-ACS-RF and GER-GCS-RF models (the average RMSE values of eight HMs were 2.61 and 2.53 mg/kg, respectively). The highest R2 values were observed in Cd and As, with an equal value of 0.98, followed by that of Pb (R2 = 0.97). The relative prediction deviation (RPD) values of Cu and AS were greater than 1.9. Moreover, the airborne-based AER-ACS-RF model presents a good mapping effect about the concentrations (mg/kg) of eight HMs in mining areas, ranging from 21.65 to 31.25 (Cu), 16.38 to 30.45 (Pb), 62.02 to 109.48 (Zn), 23.33 to 32.47 (Ni), 49.81 to 66.56 (Cr), 0.09 to 0.23 (Cd), 7.31 to 12.24 (As), and 0.03 to 0.17 (Hg), respectively. [ABSTRACT FROM AUTHOR]

Relationships between soil water saturation (SWS) and the accumulation of arsenic (As), cadmium (Cd), and lead (Pb) in soils and aboveground biomass of Populus tremula and Salix caprea were explored. SWS was computed with the hydrological model ParFlow/CLM and compared to data from field observations. Plant and soil samples collected at the main pollution sources contained the highest concentrations of As, Cd, and Pb. S. caprea contained higher concentrations of As, Cd, and Pb than P. tremula. In both species, metal(loid) concentrations in leaves were significantly higher than in branches. At strongly mining-affected locations, metalloid concentration in the trees largely reflected the pollution levels in the soil. In remote study locations, the soil–plant transfer of Cd and Pb was affected by water saturation: element accumulation increased significantly with soil moisture. Results demonstrate that coupling field observations with hydrological modelling is a promising approach for estimating element accumulation. [ABSTRACT FROM AUTHOR]

Plants are often exposed to non-ideal conditions during their growth. The toxicity of heavy metals as abiotic stressors is a significant concern due to their harmful effects on plants. Glycine betaine (GB) is a potent compatible solute that helps plants resist abiotic stresses and plays a crucial role in alleviating them. This study aimed to determine the effective role of glycine betaine (0.5 and 1 mM) as a foliar treatment in sugar beet plants to cope with the toxicity of cadmium (50 mg/kg soil) and lead (100 mg/kg soil). The application of lead (Pb) and cadmium (Cd) in cultivation soil noticeably suppressed morphological growth attributes, such as chlorophylls, carotenoids, sugars, and proteins. At the same time, the aforementioned levels of heavy metals significantly increased the levels of non-enzymatic antioxidants (phenolics and proline) and enzymatic antioxidants (peroxidase, superoxide dismutase, polyphenol oxidase, and catalase) in the root and shoot tissues of sugar beet plants. In contrast, the use of glycine betaine as foliar treatment at 0.5 and 1 mM alleviated the adverse impacts of cadmium and lead by promoting the aforementioned attributes. Furthermore, the application of 1 mM GB was more effective in increasing the contents of phenolics in root by approximately 16% and 29%, phenolics in shoot by about 25% and 10%, peroxidase activity by about 82% and 116%, superoxide dismutase activity by about 56% and 47%, polyphenol oxidase activity by about 9% and 36%, catalase activity by about 19% and 25%, in cadmium- and lead-stressed plants, respectively. Additionally, it reduced the levels of proline in sugar beet tissues. Overall, the application of glycine betaine has the efficacy to counteract the adverse impacts of cadmium and lead toxicity on sugar beet plants by enhancing the metabolic indices as well as the non-enzymatic and enzymatic antioxidant activities. [ABSTRACT FROM AUTHOR]

Despite the importance of breastfeeding, complementary or complete feeding with infant formula is performed worldwide. Metal contaminants, especially lead and cadmium, have many toxic and adverse effects, especially in children. Therefore, this work was conducted to investigate the levels of lead and cadmium in infant formula and baby foods. This study was performed on 18 samples of infant formula and 7 samples of baby food. Random sampling was performed among the best-selling and most consumed brands available in the Zahedan market, and elements were measured by atomic absorption spectroscopy using a graphite furnace. Moreover, Estimated Daily Intake (EDI) and health risk index (HRI) were calculated for the average of the total data. The mean concentrations of lead in infant formula and baby food samples were 14.7±0.98 and 13.77±1.51 µg/kg, respectively; lead was observed in all samples, although the difference between the amount of lead in samples no. 2 and no. 9 and its standard amount was significant (p<0.05). The average concentrations of cadmium in infant formula and baby food samples were 0.097±0.016 and 0.705±0.12 µg/kg, respectively; it was observed in 22% of infant formula samples and 57% of baby food samples, but the difference in cadmium concentrations in the samples was not significant compared to the standard concentration (p>0.05). The highest EDI for lead in infant formula for ages of 0 to six months was 0.22 µg/kg.day.bw. Also, the HRI for all samples was much less than one, which indicates that the baby's food and infant formula are healthy in terms of daily intake of cadmium and lead. Finally, it can be concluded that the amount of cadmium and lead in the infant formula and baby food samples, according to some indicators, is less than the standard level. [ABSTRACT FROM AUTHOR]

Suvarna bhasma (SB) contains gold and lead, which are highly potent metals and are toxic in their crude form. This study evaluated the safety profile of the medication. Suvarna bhasma was administered for 90 consecutive days orally at three doses (10.23 mg kg-1, 40.92 mg kg-1 and 102.3 mg kg-1 body weight) to wistar rats. Clinical observations, feed and water consumption, and body weight changes were noted during the study period. On the 91st day, hematological, biochemical and histopathological changes were studied. There was a significant decrease in body weight of rats at a low dose (10.23 mg kg-1) at fourth week, which could not be correlated with feed and water consumption findings. Thus, change was not considered as a treatment-related effect. Suvarna bhasma showed no evident untoward effect in haematological, biochemical and histopathological parameters in the 90 day-subchronic toxicity study (OECD 408 guidelines) and was safe in Wistar rats. [ABSTRACT FROM AUTHOR]

Heavy metals have negative impacts on human health including red blood cells hemolysis and increases oxidation processes, leading to many health issues. In this study, several blood samples were collected from people who work in North Oil Company, Kirkuk, Iraq. In addition to people who live, work away from oil fields as the control group. This investigation looks at the impact of various concentrations of cadmium and / or lead individually and combined (Cd:Pb) on erythrocytes hemolysis. The findings demonstrated that hemolysis produced by the (100 mM) were (72.0, 88.80, and 96.90%) for (Cd, Pb, and Cd: Pb) respectively. Vitamins (B2 and C) were applied with different concentrations (0.1, 0.2, 0.3, 0.4, and 0.5 mol/L). to investigate the reduction of hemolysis percentage. The findings showed that both vitamins have positive effect in reducing the hemolysis percentage. Vitamin C has even more significant impact in reducing the hemolysis compared to Vitamin B2. In conclusion, cadmium and lead can cause erythrocyte hemolysis individually or combined, additionally, vitamins C and B2 were proved to in reducing hemolysis effectively. [ABSTRACT FROM AUTHOR]

Heavy metal toxicity is a known problem and various methods are used for treatment. Adsorption has some advantages and it would be promising if environmentally friendly and cheap materials were utilized. Alginate and zinc oxide nanoparticles were selected and composite alginate beads were used for the removal of mixed metals from aqueous solutions. Batch and column experiments were conducted to determine some parameters' effects and the adsorbent's real application potential. According to the batch experiments, zinc oxide nanoparticles to alginate ratio of 0.5 g g−1, and pH levels nearby to the neutral range led to better metal removals. 0.5 ml min−1 of flow rate supplied better metal removal efficiencies in columns, with the highest treatment as 86% of Pb2+. Acid treatment can be successfully applied for the regeneration of the adsorbent, at least three times only with a 4% reduction in the adsorption efficiency. Heavy metal uptake was compatible with the pseudo 2nd order model indicating chemisorption as a dominant mechanism. Also, the intraparticle diffusion model illustrated adsorption might govern more than one step. The Langmuir model had the best fit and suggested monolayer covering for Pb2+, 76.3 mg g−1. Alginate-based nanocomposite beads were useful for mixed metal removal and could be used. [ABSTRACT FROM AUTHOR]

Rationale: Contamination of everyday goods with heavy metals such as nickel, cadmium, and lead known to be hazardous to the health of customers is an ongoing problem. Method: Here, a mass spectrometric screening method based on reactive desorption electrospray ionization (DESI) is presented for the analysis of metals in consumer goods such as jewelry, tableware, and paintings. The method detects oxidized species of lead, nickel, cadmium, copper, and iron from the surface of objects without sample preparation. Positively charged metal ions form singly and doubly negatively charged complexes with ethylenediaminetetraacetic acid added to the DESI solvent, which are analyzed by a mass spectrometer. Results: Qualitative and quantitative performance of the method was elucidated with metal salt standards. Subsequently, authentic samples were analyzed qualitatively. Reactive DESI‐MS was able to detect lead and cadmium in eight out of nine consumer goods. For tableware, these heavy metals were found to be localized in the print as determined by reactive DESI imaging. In addition, mockup paintings generated from modern and historical pigments of Pb, Cu, Cd, and Fe in various media (acrylic binder, egg tempera, and linseed oil) were measured to show the suitability of the method for art authentication and conservation. Conclusion: The developed method expands the range of analytes accessible by DESI‐MS to metal ions. Hence, DESI becomes a suitable ionization technique for an increasing number of analyte classes, which are of interest in chemical screening of consumer goods. [ABSTRACT FROM AUTHOR]

• The present study exerted heavy metal (Lead) accumulation and translocation capability of Withania somnifera shoots under lethal and non-lethal doses of Lead • In planta synthesis of Lead nanoparticles indicates that the presence specialized detoxification, sequestration and reduction mechanism in in vitro shoot cultures of Withania somnifera • Adsorption and translocation of Lead to aerial parts (stems and leaves) of the cultures was facilitated by liquid culture medium, and the addition of plant growth regulator (BAP), chelating agent (EDTA) and other mineral ions (Mg2+, K2+, Ca2+ and others) in the growth medium • Shoots exposed to non-lethal doses of Pb (800 µM) over prolonged period (12 days), significantly increased biomass and secondary metabolite (withanolides) production. Green synthesis of nanoparticles using biological extracts/live organisms has been the best substitute for chemical/physical synthesizing methods. Live plants can convert simple metal ions into metal nanoparticles using their intrinsic metabolic processes. In addition, medicinal plants with a hyperaccumulation potential also have high reduction potential which can be utilized for in planta synthesis of metal nanoparticles. Lead (Pb), a non-essential heavy metal, is known to stimulate various biological processes in plants at higher concentrations. Therefore, a medicinal plant with a hyperaccumulation potential was selected to investigate its potential for in planta reduction of Pb. In the present study, in vitro grown 45 days old Withania somnifera (L.) Dunal shoots were exposed to lead acetate (PbAC 2) at varying concentrations (acute: 300–4800 µM; chronic: 50–800 µM) for 12–48 h and 4–12 days, respectively. It revealed that cultures grown in 800 µM PbAC 2 for 12 days of exposure (C5) recorded significantly higher biomass (17.28 g) and increase in the divalent metal ions such as calcium from 1412 (control) to 1787 mg kg-1 (C5), potassium 21,109 (control) to 24,779 mg kg-1 (C5), and iron from 11 (control) to 82 mg kg-1 (C5), with lead (Pb) accumulation reaching up to 405 mg kg-1 (C5). Compared to the control shoots (0.783, 0.805 & 1.3 mg g-1), C5 shoots positively correlated with secondary metabolites namely withaferin A (3.14 mg g-1) and withanolide A (0.960 mg g-1) production and negatively with withanone (1.027 mg g-1). Also, C5 shoots had spherical shaped nanoparticles with a mean particle size of 25±10 nm which was then identified as lead nanoparticles (PbNPs). To our knowledge, the present study is the first of its kind where the in planta synthesis of PbNPs/PbONPs by in vitro shoot cultures of W. somnifera is reported along with accumulation of higher biomass and selective withanolides under Pb stress. [ABSTRACT FROM AUTHOR]

Lead (Pb) is the most common heavy metal contaminant in the environment, and its concentration is continuously increasing owing to anthropogenic activities. Phytoremediation is a green technique used globally to remediate polluted soils. The role of weeds as potential phytoremediation agents has rarely been reported in the literature. Weeds are more tolerant to abiotic stress; hence, it was hypothesized that these can serve the purpose more efficiently. Therefore, a pot experiment was conducted to evaluate the phytoremediation potential of five winter weeds, namely Avena fatua, Phalaris minor, Coronopus didymus, Chenopodium murale, and against various levels of Pb stress: control, 100 and 200 ppm. Results depicted that all the weeds could survive under higher levels of Pb; nonetheless, exposure to 200 ppm Pb stress reduced shoot dry weight (29%-69%) across all weeds. The internal CO2 concentration, photosynthesis rate, stomatal conductance, and transpiration rate decreased (5-60%) among all weeds with increasing Pb stress levels. However, Avena fatua, Phalaris minor, and Chenopodium murale depicted better gas exchange attributes than other weeds. Moreover, increased (4-60%) antioxidant activity was observed in all weeds at 100 ppm Pb level; nevertheless, it decreased at 200 ppm Pb. Additionally, Pb concentration was highest in Avena fatua, Phalaris minor, and Coronopus didymus (60-75 ppm), and the bio-accumulation factor showed that Avena fatua and Coronopus didymus were the accumulators of Pb. The translocation factor of Phalaris minor was more than 1, depicting that Pb was translocated more into shoots from roots; all other weeds accumulated more Pb in their roots than shoots. Thus, it can be concluded that different winter weeds can thrive under Pb stress, and Avena fatua and Coronopus didymus can serve the purpose of phytoremediation [ABSTRACT FROM AUTHOR]

This study was to assess the concentrations and dangers of heavy metal contamination in soil and food crops on farmlands around an alluvial gold mining site in Ghana. At the sites, 40 soil samples were obtained from ten randomly dug mini holes at depths of 0 to 40 cm as well as 12 cassavas which were analyzed for cadmium (Cd), lead (Pb), copper (Cu), and zinc (Zn). Concentrations of Cd (0.08 g/kg), Pb (0.44 mg/kg), Cu (0.27 mg/kg), and Zn (1.74 mg/kg) in the soil were found to be below the WHO/GEPA guidelines. The mean concentrations of Cd (0.65 mg/kg) and Pb (1.36 mg/kg) were beyond the WHO/GEPA stipulated limit except for Cu and Zn in food crops. Bioaccumulation factor > 1 was recorded for Cd and Zn, which implies possible health risks. Values for non-carcinogenic health risks in adults and children ranged from 0 to 0.002, with the ingestion route representing the highest contributor. Cancer risk assessments for the exposure routes were all above the US EPA tolerable range of 1.0 × 10−6 to 1 × 10−4, with Cd being the highest contributor to cancer risk. The results from this study indicate that the populace is at risk of potential health problems. [ABSTRACT FROM AUTHOR]

The monitoring of essential and toxic elements in patients with Opioid Use Disorder (OUD) undergoing methadone treatment (MT) is important, and there is limited previous research on the urinary levels of these elements in MT patients. Therefore, the present study aimed to analyze certain elements in the context of methadone treatment compared to a healthy group. In this study, patients with opioid use disorder undergoing MT (n = 67) were compared with a healthy group of companions (n = 62) in terms of urinary concentrations of some essential elements (selenium (Se), zinc (Zn), copper (Cu), iron (Fe), manganese (Mn), calcium (Ca)) and toxic elements (lead (Pb), cadmium (Cd), arsenic (As), and chromium (Cr)). Urine samples were prepared using the acid digestion method with a mixture of nitric acid and perchloric acid and assessed using the ICP-MS method. Our results showed that the two groups had no significant differences in terms of gender, education level, occupation, and smoking status. Urinary concentrations of Se, Cu, and Fe levels were significantly lower in the MT group compared to the healthy subjects. However, the concentrations of Pb, Cd, As, Mn, Cr, and Ca in the MT group were higher than in the healthy group (p < 0.05). No significant difference was established between the levels of Zn in the two groups (p = 0.232). The results of regression analysis revealed that the differences between the concentration levels of all metals (except Zn) between two groups were still remained significant after adjusting for all variables (p < 0.05). The data obtained in the current study showed lower urinary concentrations of some essential elements and higher levels of some toxic elements in the MT group compared to the healthy subjects. These findings should be incorporated into harm-reduction interventions. [ABSTRACT FROM AUTHOR]