Concentrations Of Pb Research Articles

Biomass yield and metal phytoextraction efficiency of Salix and Populus clones harvested at different rotation lengths in the field experiment

BackgroundPhytoextraction belongs to environmentally well-accepted remediation technologies to remove metals from contaminated soils. Due to long-time requirement, sufficient data for proper phytoextraction evaluation are missing. Four clones of fast-growing trees: two willow species (S1), Salix viminalis L. (Salix schwerinii E.L.Wolf × S. viminalis) × S. viminalis) and (S2)—Salix smithiana (Salix × smithiana Willd.), and two poplar clones (P1), Populus Max-4 (Populus nigra L. × Populus maximowiczii A. Henry) and (P2) Wolterson (P. nigra L.) were cultivated under field conditions at medium-to-high Cd and Pb, and low Zn soil contamination to assess trees’ long-term ability of biomass production and removal of potentially toxic elements (PTEs). The biomass yield and PTE uptake were measured during 8 years of regular growth under three rotation lengths: four harvests following 2-year periods (4 × 2y), two harvests in 4-year periods (2 × 4y), and one harvest representing 8 years of growth (1 × 8y).ResultsIn most cases, the highest annual dry biomass yield was achieved with a 2 × 4y rotation (P1 = 20.9 t ha−1 y−1, S2 = 18.4 t ha−1y−1), and the yield decreased in order 2 × 4y > 1 × 8y > 4 × 2y of harvesting periods. Only clone S1 showed a different pattern. The differences in biomass yield substantially affected the PTE phytoextraction. The greatest amount of Cd and Zn was removed by willow S2, with the highest biomass yield, and the strongest ability to accumulate PTEs. With 2 × 4y rotation, S2 removed a substantial amount of Cd (9.07%) and Zn (3.43%) from the topsoil horizon (0–20 cm) and 5.62% Cd and 2.04% Zn from horizon 20–40 cm; phytoextraction rate was slightly lower for 1 × 8y rotation. The poplar P1 removed the most Pb in the 1 × 8y rotation, but the overall Pb phytoextraction was negligible. The results indicated that lignin and cellulose contents increased, and hemicellulose content decreased with increased concentrations of Cd, Pb and Zn in poplars wood.ConclusionsThe data confirmed that phytoextraction over longer harvest periods offered promising results for removing Cd from medium- to high-level contaminated soils; however, the ability of Pb removal was extremely low. The longer harvest period should be more economically feasible.Graphical

Characteristics and risk assessment of potentially toxic elements pollution in river water and sediment in typical gold mining areas of Northwest China

To assess the concentration characteristics and ecological risks of potential toxic elements (PTEs) in water and sediment, 17 water samples and 17 sediment samples were collected in the Xiyu River to analyze the content of Cr, Ni, As, Cu, Zn, Pb, Cd and Hg, and the environmental risks of PTEs was evaluated by single-factor pollution index, Nemerow comprehensive pollution index, potential ecological risk, and human health risk assessment. The results indicated that Hg in water and Pb, Cu, Cd in sediments exceeded the corresponding environmental quality standards. In the gold mining factories distribution river section (X8-X10), there was a significant increase in PTEs in water and sediments, indicating that the arbitrary discharge of tailings during gold mining flotation is the main cause of PTEs pollution. The increase in PTEs concentration at the end of the Xiyu River may be related to the increased sedimentation rate, caused by the slowing of the riverbed, and the active chemical reactions at the estuary. The single-factor pollution index and Nemerow pollution index indicated that the river water was severely polluted by Hg. Potential ecological risk index indicated that the risk of Hg in sediments was extremely high, the risk of Cd was high, and the risk of Pb and Cu was moderate. The human health risk assessment indicated that As in water at point X10 and Hg in water at point X9 may pose non-carcinogenic risk to children through ingestion, and As at X8–X10 and Cd at X14 may pose carcinogenic risk to adults through ingestion. The average HQingestion value of Pb in sediments was 1.96, indicating that the ingestion of the sediments may poses a non-carcinogenic risk to children, As in the sediments at X8–X10 and X15–X17 may pose non-carcinogenic risk to children through ingestion.

Accumulation and translocation of lead in vegetables through intensive use of organic manure and mineral fertilizers with wastewater

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.

Effectiveness of Activated Carbon from Nutmeg Shell (Myristica fragrans) Waste as Adsorbent for Metal Ions Pb(II) and Cu(II) in Liquid Waste

Various wastes can be utilized to produce activated carbon, one of the wastes that can be utilized is nutmeg shell (Myristica fragrans). Activated carbon from nutmeg shells (Myristica fragrans) was used in this study to reduce the content of Pb(II) and Cu(II) ions in liquid waste. This research utilized the adsorption method with the batch system to determine the optimum contact time, optimum pH, and adsorption capacity. The characterization of activated carbon was done by Scanning Electron Microscopy (SEM) and Surface Area Analyzers (SAA). The content of Pb(II) and Cu(II) ions in the filtrate after adsorption was analyzed using an atomic absorption spectrophotometer (AAS). The results of SEM analysis showed that the carbon surface was cleaner and had more open pores after the activation process than before activation. The carbon surface area is 19.6243 m2.g-1. From the results of AAS analysis, the optimum time and pH for Pb(II) and Cu(II) ions was 40 min at pH 5 and 70 min at pH 4. With the Freundlich isotherm method, the adsorption capacity of the adsorbent for Pb(II) ions was 9.6028 mg.g-1 and Cu(II) ions was 0.035 mg.g-1, and the adsorption effectiveness on liquid waste for Pb and Cu metals was 1.9454 mg.g-1 and 0.4251 mg.g-1, respectively. The results showed that activated carbon from the nutmeg shell (Myristica fragrans) was able to reduce the levels of Pb(II) and Cu(II) ions in liquid waste.

Growth, gas exchange, and leaf anatomy of Echinodorus grandiflorus (Cham. & Schltr.) Micheli under Pb contamination.

Lead (Pb) can be deposited in aquatic environments that are especially subject to pollution due to wastewater and sewage disposal. This study aimed to evaluate the tolerance of Echinodorus grandiflorus (Cham. & Schltr.) Micheli to Pb and changes in growth, gas exchange, and leaf anatomy. Experiments were conducted with E. grandiflorus plants exposed to the following Pb concentrations in nutrient solution: [0; 0.75; 1.5; 3.0 and 9.0μM Pb (NO 3)2] in a greenhouse for 60days. At the end of the experiment, the lead concentration, growth, leaf gas exchange, and changes in leaf anatomy were evaluated. There was no mortality of E. grandiflorus plants, and they accumulated higher concentrations of Pb proportional to the concentration of the pollutant in the solution. Pb did not cause significant changes in growth, stomatal conductance, transpiration, and Ci/Ca rate but reduced the photosynthesis in E. grandiflorus. The leaf anatomy showed significant changes in the presence of Pb, reducing the epidermis and chlorophyll parenchyma. E. grandiflorus demonstrated tolerance to Pb, surviving and growing under contamination; however, it negatively modified its leaf anatomy and photosynthesis in the presence of the metal.

RBOH-dependent H2O2 burst induced by silicon dioxide nanoparticles establishes systemic acquired acclimation in quinoa under lead toxicity

The role of silicon dioxide nanoparticles (nSiO2) and hydrogen peroxide (H2O2) in heavy metal tolerance of plants has been well defined; however, their interaction together remains largely unknown. Therefore, two experiments were conducted to determine whether RBOH-dependent signaling is involved in nSiO2-induced systemic lead (Pb) acclimation in Chenopodium quinoa. In the first experiment, quinoa leaves were sprayed with nSiO2 (0, 2, 4 mM) under various Pb concentrations (0, 200 and 400 µM). After 12 h, an H2O2 burst, and higher transcription levels of RBOHD and PCS1 genes (encoding NADPH oxidase and phytochelatin synthase) were recorded in leaves of nSiO2-treated plants. After 15 days, Pb toxicity reduced growth parameters, and Chl a, Chl b contents and increased electrolyte leakage, and foliar spray with nSiO2 reversed this tendency. In the second experiment, foliar application of 4 mM nSiO2 minimized intracellular H2O2 and O2˙¯ and reduced malondialdehyde content and leaf Pb concentration under 400 µM Pb. While, this treatment increased the content of reduced ascorbate, and thiol compounds and enhanced the activities of superoxide dismutase and ascorbate peroxidase not only in leaves but also in untreated roots. However, H2O2 scavenging with DMTU and the inhibition of RBOH-dependent signaling by DPI aggravated Pb phytotoxicity and impaired the beneficial effects of nSiO2 on aforementioned attributes; thereby reduced tolerance index in both leaves and roots. Together, our pharmacological and molecular evidence for the first time unraveled that RBOH-dependent H2O2 burst plays vital role in triggering nSiO2-induced systemic acquired acclimation in Pb-stressed plants.

The seasonal variation of Asian dust, anthropogenic PM, and their sources in Dushanbe, Tajikistan

Central Asia's arid climate and growing population make it susceptible to air pollution from mineral dust and anthropogenic sources. To assess the impact of these pollution sources on local air quality, the chemical composition of PM10 aerosol particles was collected within a year at Dushanbe, Tajikistan. Primary sources of the pollutants, their impact on PM10 composition, and their seasonal trends were assessed. The measurement approach employed analysis of trace metals, ions, organic compounds, laboratory investigations, diagnostic ratio calculations, all complemented by positive matrix factor analysis. The results reveal that for about 70% of the year, PM10 levels (80±55 μg m−3 as the annual average) in Dushanbe were higher than the WHO limits, with varying levels during the seasons. Summer concentrations peaked up to 434 μg m−3 due to a combined mineral and road dust influence. Interestingly, winter concentrations reached 152 μg m−3 due to strong contributions (about 64%) from residential heating and fossil fuel combustion, often triggered during sub-10°C temperatures. Mineral dust events were associated with elevated concentrations of trace metals, including Zn and Pb, alongside organic carbon and high-chain n - alkanes. During such events, Ca/Fe, Ca/Al ratios exceeded those of Saharan dust, suggesting a high salt content in Asian dust, potentially influenced by dried-off lake emissions. It was striking to observe that winter periods exhibited concerning levels of carcinogenic PAHs, such as benzo(b)fluoranthene (<25 ng m−3) and benzo[a]pyrene (<12 ng m−3, BaP), with average values of 4.1 ± 5.9 ng m−3 (BaP) that significantly exceed WHO recommendations. The high PM10 and PAH exposure could pose severe health risks, necessitating collective attention from the local authorities in developing new mitigation strategies concerning the reduction of emissions from residential heating of coal and wood in winter to curb combustion emissions and reduce exposure.

Assessment of essential and toxic trace element levels in erythrocytes of hemodialysis patients with end-stage renal disease

BackgroundChronic kidney disease (CKD) is a global public health problem, resulting in end-stage kidney disease, cardiovascular disease, and premature death. AimThe aim of the study was to determine the profile of essential and toxic trace elements in erythrocytes of patients with end-stage renal disease (ESRD) and their relationship with selected anthropometric and biochemical parameters. MethodsThe present study compared the profiles of trace elements, including toxic sub-stances, in the erythrocytes of 80 hemodialysis patients with CKD with 40 healthy subjects. All patients had stage 5 CKD. The levels of Cd and Pb were determined by graphite furnace atomic absorption spectrometry and levels of Fe, Mn, Zn, Cu Cr, Ni, and Li by inductively coupled plasma atomic emission spectrometry. ResultsThe ESRD patients demonstrated significantly lower Fe and Zn concentrations and significantly higher Mn and Li and toxic Pb and Cd concentrations in erythrocytes compared to those of the healthy controls. Negative correlations were observed, among others, between the concentrations of Cu, Li, and creatinine; Cu and phosphates; Mn, Pb, and transferrin saturation while positive correlations were noted between Cu, Cr, and transferrin and Pb, Cr, and the normalized protein catabolism rate. ConclusionsThe higher concentrations of toxic elements present in the erythrocytes of CKD patients might have resulted from the reduced ability of the kidneys to excrete them. Moreover, differences in the concentrations of essential elements (Fe, Mn, Zn) between the two groups indicated that their resorption in the kidneys of CKD patients was impaired. Patients with CKD might benefit from interventions intended to reduce high, toxic concentrations of Pb and Cd and Li and Mn as an alternative supportive treatment. Iron and zinc supplementation should be a component for the treatment of anemia in CKD patients.

Assessment of toxic elements in selected fish species in the marine water at Jamestown, Ghana

Fish is an excellent source of low-fat protein. Fish contains a lot of omega-3 fatty acids, as well as vitamins D and B2 (riboflavin). The daily consumption of contaminated food, especially fish, is among the primary cause of heavy metals pollution to human health. The aim of the research was to determine the concentration of heavy metals in selected species of fish from the Gulf of Guinea at James Town in Ghana. In tandem with the study's objective, samples of different forms of fish, Cassava fish, Flatfish, Redfish, Kingfish, and Silverfish, and sediment were obtained and analyzed for the presence of heavy metals using atomic absorption spectrometer (PerkinElmer®, PinAAcle 900T). The analysis indicated a high concentration of Pb, Cd, and Cr concentrations in fish gills, muscles, and sediment. High lead concentration in Silverfish gills (5.9 mg/kg) and Flatfish gills (2.29 mg/kg) above WHO levels. Cadmium was found in all fish species and sediment except Kingfish. Chromium concentrations were high n Cassava fish (3.10 mg/kg) and Silverfish (4.01 mg/kg) and copper concentrations were absent in the fish species. Arsenic and mercury were also not detected in all fish species and sediment. Manganese concentrations were found in fish and sediment. High cadmium target hazard quotient (0.17–11.60 for adults and 0.24 to 16.24 for children) and cancer risk (0.00–0.04) values in fish samples indicated potential health concerns. The Hazard Index (HI) for the analyzed samples ranged from 0.00 to 12.48 for adults and 0.00 to 17.47 for children. The study suggests that eliminating pollution and other sources of waterbody pollution is crucial to protecting the marine environment and the health of seafood consumers.

Pb(II) and chlortetracycline immobilization and economy of biologically amended coastal soil

To study the pollutants immobilization and economy of biologically amended coastal soil, Alternanthera philoxeroides biomass (Bm), biochar (Bc), and dodecyldimethyl betaine (BS) modified Bc (BS-Bc) were used to amend coastal soil from Jialing, Fu, and Qu River. A runoff experiment was used to simulate the longitudinal migration and morphological changes of Pb(II) and chlortetracycline (CTC) in each amended coastal soil, and the economy of pollutants immobilization by different amended coastal soil were compared. The equilibrium time of Pb(II) and CTC in each amended coastal soil ranked in the order of BS-Bc-amended > Bc-amended > Bm-amended > unamended coastal soil. The average Pb(II) and CTC flow rate in different amended coastal soils presented an opposite trend with the equilibrium time. Pb(II) and CTC content all reduced with the increasing runoff length. Under the same soils, the content changes presented Bm and Bc amended > unamended > BS-Bc amended. CEC and clay content of coastal soils were the key factors affecting Pb(II) and CTC immobilization. The immobilization mechanisms were electrostatic attraction, ion exchange, surface precipitation, and complexation to Pb(II) and ion exchange and complexation to CTC. The economy of Pb(II) and CTC immobilization ranged from 0.5 to 9.0 and from 1.0 to 5.4 mg/¥, and coastal soil amended by BS-Bc had practical application value and high economy.

Occupational and human health risks of exposure to potentially toxic elements (PTEs) in top soils from steel fabrication workshops

IntroductionEnvironmental pollution caused by potentially toxic elements (PTEs) from anthropogenic sources has become a global concern due to its deleterious effect on humans and ecosystem health. Therefore, this study evaluated the concentrations of PTEs, pollution level and human health risk in topsoil from ten (10) steel fabrication workshops in Abeokuta, Ogun State, Nigeria. Materials and methodsTen (10) composite soil samples were collected in November 2023, from 10 different steel fabrication workshops in proximity to residence in Abeokuta, Ogun State, Nigeria. One (1) gram of processed sample was digested using aqua regia and PTE concentration estimated using atomic absorption spectrophotometer (AAS). Pollution index assessment was determined using enrichment factor (EF) and geo-accumulation index (I-geo) while descriptive statistics and correlation were subjected to statistical package for social sciences (SPSS). ResultsThe result showed that Iron (Fe) (11,500 – 42,100 mg kg−1), Lead (Pb) (10.7 – 583 mg kg−1), Chromium (Cr) (16.3 - 49.7 mg kg−1), Zinc (Zn) (34.6 – 343 mg kg−1), Manganese (Mn) (109 – 840 mg kg−1), Nickel (Ni) (2.23 - 25.3 mg kg−1), Copper (Cu) (16.6 -107 mg kg−1) and Cadmium (Cd) (2.23 - 25.3 mg kg−1) were present. Mean concentration for Pb (179±202 mg kg−1) is higher than the Canada soil guideline value (CSGV) (140 mg kg−1) while other PTEs are within the recommended limit. Pollution indices revealed EF (Cd and Pb) and I-geo (Cd) as the primary pollutants in the soil while the strong significant correlation between Cr, Cu and Mn p < 0.05. Cr, Ni, Pb and that of Cu, Mn, Ni, Pb, Zn p < 0.01 suggest an emanation from both geogenic and anthropogenic sources. Human health risk assessment revealed Fe as the most dosed PTE and ingestion as the major pathways of exposure especially to children being the most susceptible. Hazard index (HI) and total cancer risk (TCR) values for PTEs were <1 and within the acceptable threshold (1 × 10−6 – 1 × 10−4) except for Pb (3.93E+01; 1.16E-03) in adults respectively. ConclusionThe study showed that the topsoil from the steel fabrication workshop is polluted with Pb and Cu toxicity and the adult (residents and workers) population exposed to the soil is potentially at a non-cancer and cancer risk.

Lead exposure estimation through a physiologically based toxicokinetic model using human biomonitoring data and comparison with scenario-based exposure assessment: A case study in Korean adults

Pb toxicity is linked to cardiovascular and nephrotoxicity issues. Exposure to this heavy metal can occur through food and drinking water. Therefore, this study aimed to evaluate Pb exposure and assess health risks in Korean adults using a physiologically based toxicokinetic (PBTK) model. Human blood Pb concentrations were monitored using the Korean National Environmental Health Survey (KoNEHS) Cycle 4. The average Pb exposure in Korean adults was 0.520 μg/kg bw/day. The PBTK results were compared with scenario-based results from the 2021 risk assessment report of five heavy metals, including Pb, conducted by the MFDS. Exposure determined through reverse dosimetry was approximately two times higher than scenario-based exposure (0.264 μg/kg bw/day). The higher exposure levels obtained during PBTK analysis may be attributed to sustained exposure within historically more contaminated living environments and the long half-life of Pb. These findings suggest that the PBTK-based method can quantify aggregated exposure levels in the body over time, potentially serving as a complementary tool to address the constraints of scenario-based assessment methods for integrated risk assessment. Moreover, this model is convenient and cost-effective compared with scenario-based exposure estimation. These findings can facilitate the application of model for tracking continuous national changes in hazardous substance levels.

Preparation of F/Mn-doped CsPb(Br/Cl)3 quantum-dot glass and their luminescence properties

All inorganic lead halide cesium perovskite quantum dots (QDs) have attracted much attention due to their excellent luminescence properties, but further development is restricted by their stability and the existence of toxic element lead. In this paper, F/Mn-doped CsPb(Br/Cl)3 QDs glass was prepared by melt quenching and heat treatment, with reduced Pb content effectively. The result shows that the spectrum of the QD glass is adjustable between 450 nm and 515.4 nm by changing the feeding ratio of Mn-Pb ion and heat treatment temperature. Moreover, the indraught of Mn[Formula: see text] effectively improves the PLQY of CsPb(Br/Cl)3 QDs glass and serves as a red-emitting. The prepared composites not only maintain good fluorescence characteristics, but also greatly improve the stability of QDs. And successfully coupled with blue LED chips to synthesize WLED, Under 20 mA current, the color coordinate is (0.3446, 0.3389).

The possible application of fly ash (FA) to ameliorate acid mine water (AMD) for irrigation of potato (Solanum tuberosum L.)

Some areas in Johannesburg abounds with mine wastes namely, acid mine drainage (AMD) as well as fly ash (FA), which are by-products of gold mining and coal burning, respectively. Studies show that a solution formed through mixing these wastes neutralises the acidity of AMD and is an alternative source of irrigation. While studies show improved growth and yield of plants irrigated with fly ash-amended AMD, there are rarely sufficient studies conducted in South Africa showing evidence of altered pH of AMD and that food crops irrigated with fly ash-amended AMD exhibit improved concentration of essential nutrient elements. In this study, AMD was sourced from a gold mine in Johannesburg and fly ash collected from a coal-burning power station in the Mpumalanga Province, mixed at 1:0, 1:1, and 3:1 (w/v) of fly ash to AMD and used to irrigate potatoes. The objective was to assess whether the solutions of FA-amended AMD alter the pH of the AMD and to evaluate if irrigating potatoes with the aforementioned improve the concentration of essential nutrient elements and heavy metals in the tubers. Results show that the pH of AMD was increased in the 1:0 and 1:1 solutions but decreased in the 3:1 solution. The concentrations of Pb and Co were decreased in tubers irrigated with the 50 % AMD and 75 % AMD while that of Ni and Cd were markedly increased in tubers irrigated with solutions of fly ash-amended AMD. In the main, the potato tubers exhibited significantly higher concentrations of Al, Mo, Cu, Ca, Mg, and Zn when irrigated with fly-ash-amended AMD. The pH range levels from FA-AMD treated samples were within the acceptable pH range (5.5–6.5) which is acceptable for water that could be used for irrigation of crops. Also, the decreased Co and Pb and improved concentration of essential nutrient elements indicate that the constituents absorbed large quantities of the heavy metals while releasing the nutrients. In conclusion, the selected fly ash has proven as an alternative low-cost readily-available, affordable, and accessible adsorbent that neutralize the acidity of AMD, decrease the concentration of heavy metals, and increase the concentration of essential nutrient elements. Importantly, the liming potential among other traits of the fly ash improved the quality of the AMD such that the wastes were proven in this study suitable to irrigate potatoes.

Health risks of metals in soils and staple foods of the subsistence food gardens in the floodplains of Watut River, Papua New Guinea.

The health risks associated with the consumption of staples cultivated in the subsistence food gardens along the Watut River were investigated in Papua New Guinea. Twenty soil samples and twenty-nine samples of staple foods (including banana, taro, sweet potato, and Singapore taro) were collected from the food gardens following a three-day dietary recall survey. The concentration of metals (Cr, Cu, Pb, and Ni) was analyzed in the soil and food samples using Inductively Coupled Plasma Optical Emission Spectrophotometer. The descending order of mean metal concentration in the food garden soils is as follows: Cr > Cu > Ni > Pb. The concentration of Pb in all samples and Cr in 97% of staple foods exceeded the FAO/WHO permissible limits. Approximately 87% of adult consumers of bananas (Musa sp) were found to have estimated Cr and Pb ingestion levels exceeding the permissible daily tolerable intake of metals (0.2 and 0.21mgday-1, respectively). Hazard index values from the staples analysis indicate that the consumption of bananas (9.40) poses the highest risk of non-carcinogenic effects on adults, followed by taro (7.32), sweet potato (6.13), and Singapore taro (4.30). The consumption of taro is dangerous due to cancer risk associated with the intake of excessive Ni (2.88E-02) and Cr (8.82E-03) in adults and children compared to banana, sweet potato, and Singapore taro. Non-carcinogenic hazards of metal ingestion were found to be pronounced in the younger population, while carcinogenic effects were more serious in adults. Urgent measures must be implemented to protect communities, especially children, from the dangerous effects of heavy metal ingestion through staples in the lower Watut region.

Salicylic acid foliar application meliorates Portulaca oleraceae L. growth responses under Pb and Ni over-availability while keeping reliable phytoremediation potential

The efficacy of SA foliar use on Pb and Ni-induced stress tolerance and phytoremediation potential by Portulaca oleraceae L. were assayed as a factorial trial based on a completely randomized design with four repetitions. The factors included; SA foliar application (0 and 100 µM) and HMs application of Pb [0, 150, and 225 mg kg−1 soil Lead (II) nitrate] and Ni [0, 220, and 330 mg kg−1 soil Nickel (II) nitrate]. Plant height, stem diameter, shoot and root fresh and dry weight, photosynthetic pigments, total soluble proteins, palmitic acid, stearic acid, arachidic acid, and some macro- and micro-elements contents were reduced facing the HMs stress, but SA foliar application ameliorated these traits. HMs stress increased malondialdehyde content, total antioxidant activity, total flavonoids, phenolics, and linolenic acid content, while SA foliar application declined the mentioned parameters. Moreover, shoot and root Pb and Ni content enhanced in the purslane plants supplemented by SA under the HMs stress. The results propose SA foliar application as a reliable methodology to recover purslane growth characters and fatty acid profiles in the soil contaminated with the HMs. The idea is that SA would be potentially effective in alleviating HMs contamination while keeping reasonable phytoremediation potential.

Spatial diffusion of potentially toxic elements in soils around non-ferrous metal mines

This study focuses on the diffusion patterns of principal ore-forming elements (Pb and Zn) and associated elements (Cd, Cu, Cr, and As) in lead-zinc ore. Sampling points in upwind and downwind directions of lead-zinc ore areas at various densities (1 N/km2 – 4 N/km2) were categorized. This study analyzed the statistical relationship between the content of PTEs in the soil around lead-zinc ore and the source strength and dominant wind direction, constructed one-dimensional and two-dimensional diffusion model, and simulated the EER scope caused by PTEs. The findings indicate that: (1) concerning source strength, the content of PTEs in soils of high-density ore aggregation areas is significantly higher than in low-density ore aggregation areas. However, the impact of source strength decreases with decreasing ore grade, with a difference in Pb content of 1.71 times among principal ore-forming elements and almost consistent Cd content among associated elements. (2) Regarding the transport pathways, for most PTEs, the inverse proportion coefficients downwind are higher than upwind, approximately 1.18–3.63 times, indicating greater migration distances of PTEs downwind due to atmospheric dispersion. (3) By establishing a two-dimensional risk diffusion model, the study simulates the maximum radius of risk diffusion (r = 5.7 km), the 50% probability radius (r = 3.1 km), and the minimum radius (r = 0.8 km) based on the maximum, median, and minimum values statistically obtained from the EER. This study provides a scientific basis for implementing preventive measures for PTEs accumulation in soil within different pollution ranges. Different risk prevention and control measures should be adopted for PTEs accumulation in soil within the three ranges after cutting off pollution sources. Subsequent research should further investigate the impact and contribution of atmospheric transmission and surface runoff on the diffusion of PTEs in areas with high risk near lead-zinc ore.

Remediation of Pb-, Zn-, Cu-, and Cd-Contaminated Soil in a Lead–Zinc Mining Area by Co-Cropping Ilex cornuta and Epipremnum aureum with Illite Application

Phytoremediation is considered an effective strategy for remediation of heavy-metal-contaminated soil in mining areas. However, single-species plants cannot reach the highest potential for uptake of heavy metals due to inhibition of their growth by high concentrations of heavy metals in the soil. Therefore, this study has explored the effects of illite application and two plant species’ co-cropping on soil quality, plant growth, and heavy metal transformation in a soil–plant system. The results reveal that the addition of 1% (mass fraction) of illite significantly enhances soil pH. The co-cropping of Ilex cornuta and Epipremnum aureum is beneficial for improving the organic matter content of the soil. The contents of EDTA-extractable Pb, Zn, and Cu were significantly reduced by 29.8–32.5%, 1.85–5.72%, and 30.0–32.9%, respectively, compared to the control. The co-cropping of Ilex cornuta and Epipremnum aureum promoted enrichment effects of Epipremnum aureum on Pb and Ilex cornuta on Cd (p &lt; 0.05). The co-cropping pattern lowered the biomass of Ilex cornuta and Epipremnum aureum; however, co-cropping of Ilex cornuta and Epipremnum aureum promoted the elimination of Pb, Zn, Cu, and Cd from the soil at 13.0–75.8%, 11.1–38.2%, 8.39–88.4%, and 27.8–72.5%, respectively. It is concluded that illite application combined with co-cropping of Ilex cornuta and Epipremnum aureum is highly effective for the elimination of Pb, Zn, Cu, and Cd from contaminated soil. This study provides a theoretical basis and pathway for the restoration of heavy-metal-contaminated soil in mining with the application of bentonite combined with phytoremediation.

Geochemical Signature and Risk Assessment of Potential Toxic Elements in Intensively Cultivated Soils of South-West Punjab, India

Soil contamination with potentially toxic elements (PTEs) in the Malwa region belt of Punjab, India, can be a serious concern as a result of intensive agricultural practices and overuse of agrochemicals. The main objectives of the present study were to evaluate the spatial distribution, geochemical signature, and contamination level/health risk of PTEs in 76 soil samples (0–10 cm) collected from the three districts viz. Muktar, Faridkot, and Moga of Punjab, India. The result shows that PTEs concentrations vary widely in the region, with Fe and Mn distribution patterns being mostly coherent with each other. When compared to the Indian natural soil background values, the average concentration of Pb and Zn were higher than the limit, only Pb exceeded the average values of the world background and upper continental crust (UCC). Spatial autocorrelation plotted with a local indicator of spatial association (LISA) in GeoDa software version 1.18 was used to identify hotspots. A positive spatial autocorrelation (&gt;0.2) was indicated with Moran’s I values for Pb, V, Mn, Cu, and Cr, being highest for Pb. A principal component analysis (PCA) identified the major geo-chemical patterns of Fe-Al-V-Cr and TOC-Mn-Zn-HCO3−, which were positively loaded on PC1. This indicates that Fe/Al-oxyhydroxides and organic matter play a dominant role in controlling metal mobility in soils. This can be further substantiated with the Spearman’s rank correlation values. The contamination factor (CF) indicates that only Pb and Zn (15.7% and 3.9% samples, respectively) were under high risk. This could be due to the excessive application of chemical fertilizers. The large range of degree of contamination (Cdeg) values suggests that there are variations in the degree of soil pollution due to PTEs. A little over 3.9% of samples had significant contamination, compared to 72.3% of samples with low contamination and 23.6% of samples with moderate contamination. Human non-carcinogenic and carcinogenic risk levels were investigated. The hazard index (HI) values for adult ranged from 0.00 to 0.2, and values for children ranged from 0.009 to 1.2. These findings suggest that both children and adults are not at potential risk, except in a few locations. Overall, the results of this study provide the current baseline status of toxic elements in agricultural soil. This would be helpful for developing strategies for sustainable management of the soil resources in the region, as well as for future monitoring programs of the soil quality in the Malwa region as a whole, to track any changes in the contamination levels over time.

Assessing soil pollution concerns in proximity to Fence-type solar photovoltaic system installations

This study conducted in the Kyungpook National University Eco-friendly Agriculture Research Centre between 2022 and 2023 investigates the environmental implications of fence-type solar photovoltaic (PV) systems in diverse agricultural settings. Despite the increasing adoption of solar energy for climate change mitigation, there is a noticeable gap in research regarding the potential environmental impact of these specific PV systems. Focusing on heavy metal concentrations, including Cadmium (Cd), Copper (Cu), Arsenic (As), Mercury (Hg), Lead (Pb), Hexavalent Chromium (Cr+6), Zinc (Zn), and Nickel (Ni), across distinct fields, the study reveals significant fluctuations. Notably, the Rice Field experienced a substantial increase in Cd levels from 0.47 mg/kg in 2022 to 1.55 mg/kg in 2023, while Cu and Pb concentrations decreased to acceptable levels in 2023. The findings underscore the dynamic nature of heavy metal concentrations, emphasizing the importance of continuous soil quality monitoring to prevent contamination. This research provides valuable insights into the impact of fence-type solar PV system installations on agricultural soil quality, emphasizing the urgent need to secure these ecosystems through vigilant monitoring and environmental management practices.