Lead Absorption Research Articles

Biomass Assessment and Optimization of Alcaligenes faecalis Isolated from some Nigerian Mining Sites for Heavy Metal Uptake Using Response Surface Methodology Model

In this study, we investigated the heavy metal absorption of Alcaligenes faecalis strain U.B.I., a bacteria isolated from a mining site, under different environmental conditions. We utilized both conventional and molecular techniques to identify the bacteria and employed response surface methodology (R.S.M.) to determine optimal environmental conditions for heavy metal absorption. Our analysis revealed that the heavy metal-tolerant bacteria belong to the Proteobacteria, specifically the Betaproteobacteria order in the Burkholderiales family. Additionally, the bacteria’s phylogenetic characteristics indicated a close relationship between the Aeromonas sp. cluster and members of the Aeromonadaceae family. Our results showed that the biomass A. faecalis strain U.B.I. had an optimal potential for chromium (Cr+) absorption at 93.0%. We also conducted tests on the biomass under optimized conditions for lead (Pb2+) absorption using R.S.M., resulting in a mean heavy metal uptake of 89.99%. Furthermore, we analyzed the surface functional groups after interaction with heavy metals and observed a significant shift in position of the functional groups. The O-H stretch and H-bonded at the 3268 cm1 position, while C=C stretch and N-O asymmetrical stretch/C-O stretch occurred at positions 2195 cm-1 and 1629 cm-1 of the spectra, respectively. Our findings suggest that the biomass of A. faecalis strain U.B.I. has potential for heavy metal bioremediation and can be used for heavy metal biosorption under various environmental conditions.

Scots Pine (Pinus sylvestris L.) Ecotypes Response to Accumulation of Heavy Metals during Reforestation on Chalk Outcrops

As objects for reforestation, the least studied are carbonate substrates, which have a number of specific features in terms of mineral composition, the exchange of nutrients, and biological activity. The use of biological preparations of a consortium of bacteria of the genus Bacillus and mycorrhizal fungi of the genus Glomus in growing seedlings of Scots pine (Pinus sylvestris L.) on carbonate substrates provides the metabolic products; soluble and microelement salts function as catalysts for chemical reactions of exudates and soil products; and a greater amount of plant heavy metals (HM) Cu, Zn, Cd, and Pb accumulate in the soil. Among HMs, the random factors most strongly determined an accumulation of Cd (the influence rate of random factors h2x = 34.6%) and Pb (the influence rate of random factors h2x = 21.7%) in the plants. A trend of all studied HMs higher uptake by the Cretaceous pine (Pinus sylvestris var. cretacea (Kalen.) Kom.) in comparison with the P. sylvestris ecotype is revealed. Against the biological preparation background of Biogor KM and MycoCrop®, a greater value of the HM’s biological absorption in comparison with the option without biological preparations is noted. This process occurs against a background of a significant increase in the nitrification capacity in the chalk fine-grained substrate (soil aggregates < 1 mm in size), which is an indirect indicator of an increased intensity of microbiological processes. Spearman’s correlation was noted between the coefficient of accumulation of Cu, Zn, Cd, and Pb in the dry matter of Scots pine (P. sylvestris) seedlings and the nitrification capacity of substrate (rs = 0.610–0.744, p < 0.05), as well as the relationship between the nitrification capacity index of substrate and the coefficient of biological absorption of copper, zinc, and cadmium (rs = 0.543–0.765, p < 0.05). No relationship was found between the coefficient of biological absorption of lead and other soil chemical property indicators. HM absorption by plants was random. No correlations have been established between an accumulation of HMs and a content of total nitrogen, an absolute value of nitrate nitrogen, a humus content, or a pH. The significance of the work is the possibility of providing reliable reforestation with Scots pine (P. sylvestris) and Cretaceous pine (P. sylvestris var. cretacea) on the chalk outcrops using the biological preparations Biogor KM, MycoCrop®, and BGT* methodology and ensuring soil phytoremediation from HMs.

APPLICATION OF BIOHUMUS FOR REDUCING THE ACCUMULATION OF HEAVY METALS IN THE SOIL AND SPRING BARLEY PLANTS IN THE DONETSK INDUSTRIAL REGION

The paper aimed to analyze the effect of the application of organic fertilizer biohumus on the content of heavy metals in the soil and spring barley plants in the Donetsk industrial region of Ukraine. Application of biohumus in the organomineral nutrition system led to decrease the content of mobile forms of copper, zinc, lead, cadmium by 17.1%, 23.4%, 22.6% and 23.1% respectively. The content of copper and zinc in the grain was almost at the control level, the accumulation level of lead and cadmium in the spring barley grain decreased by 1.6 and 1.4 times, respectively. The variant of the organo-mineral nutrition system with foliar treatment of plants with biostimulant regoplant allows to reduce the amount of traditional mineral fertilizers by up to 50% while maintaining the yield level, to reduce the coefficients of biological absorption of lead and cadmium by 1.4 times compared to the control. To reduce the risk of soil and grain contamination by heavy metals in industrial regions, it is advisable to use an organo-mineral fertilizer system.

Stability of blood lead levels in children with low-level lead absorption.

Current child blood lead (Pb) screening guidelines assume that blood lead levels (BLLs) are relatively stable over time, and that only youngest children are vulnerable to the damaging effects of lower-range BLLs. This study aimed to test the stability of lower-range (≤ 10 μg/dL) child BLLs over time, and whether lower-range BLLs diminished with age among children aged 6 months to 16 years living in a lower-income neighborhood with a density of pre-1986 housing and legacy contamination. Age, sex, family income, age of residence, and/or residence proximity to point sources of Pb, were tested as potential additional factors. Capillary blood samples from 193 children were analyzed by inductively coupled plasma mass spectrometry (ICPMS). Multiple imputation was used to simulate missing data for 3 blood tests for each child. Integrated Growth Curve models with Test Wave as a random effect were used to test BLL variability over time. Among N = 193 children tested, at Time 1 testing, 8.7% had the BLLs ≥ 5 μg/dL (CDC "elevated" BLL reference value at the time of data collection) and 16.8% had BLLs ≥ 3.5 μg/dL (2021 CDC "elevated" BLL reference value). Modeling with time as a random effect showed that the variability of BLLs were attributable to changes within children. Moreover, time was not a significant predictor of child BLLs over 18 months. A sex by age interaction suggested that BLLs diminished with age only among males. Of the additional environmental factors tested, only proximity to a major source of industrial or vehicle exhaust pollution predicted child BLL variability, and was associated with a small, but significant BLL increase (0.22 μg/dL). These findings suggest that one or two BLL tests for only infants or toddlers are insufficient for identifying children with Pb poisoning.

The absorption and accumulation of lead in dracaena sanderiana plant

Heavy metals are the most dangerous substances in the environment, have caused deleterious effect not only to the environment but also to the public’s health. Different studies have demonstrated that plants have a high removal capacity for lead ions from pollution sources. However, these plant species were rather limited. Thus, the project aimed to find out plant species that represent its lead removal ability to reduce environmental pollution. The experiment was carried out factorially as a randomized complete design in hydroponic systems with four treatments (0, 100, 200, and 300mg/l of Pb) and three replications. The results indicated that the growth of the Dracaena sanderiana plant is well in Pb concentration of 100mg/l, with less growth while the increasing lead concentration of 200 mg/l and 300 mg/l. The amount of lead in the water of three treatments 100mg/l, 200mg/l, and 300mg/l after 30 days of the experiment decreased by 91.5%, 86.8%, and 86.4%, respectively. It was found that Dracaena sanderiana exhibited high lead treatment efficiency in the water. Moreover, results showed that the accumulation of lead in the roots of Dracaena sanderiana is quite large with treatments of 100mg/l, 200mg/l, and 300mg/l lead concentrations were 5073.8mg/kg, 5134.0mg/kg, 7054.0mg/kg, respectively. In contrast, the ability to lead accumulation in plant leaves and stems is lower.

The effect of sulfur-containing compounds and thiobacillus bacteria on corn plants under field soil and soil contaminated by heavy metals lead and zinc conditions

Investigating the effect of various sources of sulfurous compounds along with the inoculation of Thiobacillus bacteria on corn plants under stress conditions of lead and zinc metals, an experiment executed at zanjan uni researching green house. The treatments include elemental sulfur (0.75, 1.25 and 2 g/kg soil), sulfur with Thiobacillus bacteria (1, 2 and 3 g/kg soil) and potassium sulfate (0.5, 1 and 1.5 g/kg soil ). The results showed that the traits were significant in all applied treatments except proline. The amount of morphological traits and physiological traits increased in sulfur treatment with thiobacillus bacteria in field soil conditions and heavy metal stress compared to the control. But the properties of soluble sugars and proline decreased in this treatment. On the other hand, with the increase in the concentration of elemental sulfur and potassium sulfate treatments that caused stress in the plant. However, under stress conditions, the amount of absorption of lead and zinc in the root and aerial part of the plant increased to a critical and damaging level, but by applying of treatments, the amount of absorption and damage decreased. it can be concluded that elemental sulfur and potassium sulfate treatments by reducing the absorption of all elements required by the plant caused stress, but sulfur with bacteria treatment reduces the absorption of these heavy elements, and the bacteria in the soil provides the conditions for absorbing more water and nutrients through the roots and improves the growth of the plant.

Constructing physical and chemical synergistic effect of graphene aerogels regenerated from spent graphite anode of lithium ion batteries achieves high efficient adsorption of lead in wastewater

The treatment and disposal of lead in wastewater is deeply troubled in industry due to the limitations of physical adsorption and exclusivity of chemical adsorption methods. Herein, an unique graphene aerogel (GA) structure, rich in active functional groups such as sulfur, carboxyl and hydroxyl, etc., is designed and synthesized from the waste graphite anode of lithium ion batteries in our work. Through the physical adsorption of the porous structure of graphene itself, combined with the chemical adsorption of special functional groups, the synergistic effect can achieve high efficiency absorption of lead in wastewater, reaching the maximum of 152.70 mg/g. The best conditions for the adsorption of lead-containing wastewater are using 50 mg of GAs for adsorbing at 30 °C for 1 h when the initial concentration is 50 mg/L. The adsorption process conforms to the Langmuir isothermal adsorption model, the adsorption dynamics conform to the quasi-secondary kinetic equation, and the adsorption activation energy is 47.29 kJ/mol, confirming that the adsorption is controlled by the chemical reaction. Owing to the superiority of waste recycling, our research provides a novel idea for the combined physical adsorption and chemical adsorption of heavy metals in wastewater.

Low-cost biodegradable lead sequestration film for perovskite solar cells

Despite the high efficiency that has been achieved for the perovskite solar cells (PSCs), the hazardous lead leakage from the perovskite absorber layer is one of the crucial barriers still hindering its penetration into the commercial market for a large-scale installation. Herein, we report a novel low-cost and biodegradable lead sequestration layer with high compatibility for up-scalable encapsulation of PSCs. Through a precisely designed cross-linking reaction of chemical agents, the as-made biodegradable chitosan composite film shows enhanced mechanical strength, chemical stability, and lead adsorption capacity. The designed encapsulation strategy reduces over 99.99% lead leakage to <2 ppb under varied simulations of weather conditions (hail, rain, or flood), which meet the safe level of drinking water set by the US Environmental Protection Agency (EPA). Moreover, the PSC efficiency is improved from 21.91% to 22.82% due to the improved light absorption from the printed biodegradable lead absorption film. Finally, we present a prototype process of accumulation and recycling of lead compounds in PSCs derbies via the biodegradation process. Based on the low-cost biodegradable lead sequestration film, this environmental-friendly encapsulation strategy could address the lead leakage issue for further commercialization of PSCs.

Assessment of the absorption ability of nitrate and lead by japanese raisin under salt stress conditions

Heavy metals pollution is an important challenge that was cussed by human activity, this stress decreases under salinity. The aim of this study was to investigate the ability of Japanese raisin in the absorption of nitrate (0, 30, and 60 mgL-1) and lead (0, 300, and 600 mgL-1) under salinity stress (0 as control and 3 and 6 dSm-1). Results showed that the studied plant continued to uptake nitrate and potassium under stress conditions of Pb and salinity. Although Na and Cl uptake were observed as a defense mechanism in the plant, the K/Na ratio, and K content increased from 1 to 6 and from 1.8 to 5%, respectively. Also, the most appropriate physiological responses were observed at treatments under contamination level of 300 mg Pb and salinity level of 3 dSm-1, so that the synthesis of malondialdehyde (MDA) and enzymatic activity increased at these levels of HMs and salinity. Based on the results, the studied species were able to uptake moderate concentrations of Pb (34.1-71mg kg-1) under experimental conditions. Hence, its potential for the clean-up of some contaminants in the environment can be considered by researchers for further research.

A review of the consequences of dangerous blood lead concentrations and strategies for its prevention

According to the available data, lead affects the cholinergic and dopaminergic pathways, thereby preventing the normal functioning of neurotransmission. Based on the analysis of existing literature, the results help us to study and define a wide range of symptoms of lead poisoning. Children absorb lead well orally (-50%), adults relatively poorly (-10%). The content of lead is often quite high in toys, in food products, in regions close to lead-based factories, in the exhaust emitted by technically defective vehicles, which enters the body through air. Lead absorption is enhanced if the daily diet is poor in iron or calcium. Lead still exists in significant concentrations in the environment, especially in modern, densely populated city centers. A 2019 study of blood lead levels among children in Georgia found that 41% of children in Georgia had blood lead levels of 5 μg/dL or higher. In order to eliminate the problems, the government of Georgia started introducing new rules, tightening the construction standards for kindergartens, inspecting imported toys, technical inspection of cars. It is important to fully implement and monitor the introduced rules and standards.

Study on the effect of lead (Pb) content in soil on the growth and lead (Pb) absorption of Vetiver grass (Vetiveria zizanioides L.)

Treatment of heavy metal pollution in soil by a biological method is currently being studied and widely applied in Vietnam. This study concentrated on the impact of lead (Pb) on the growth of Vetiver grass (Vetiveria zizanioides L.), and its capacity for lead absorption with the aim of removing them from the soil areas used for orange cultivation. Results conducted from the study showed that Vetiver grass could be grown in Pb-contaminated soil. With Pb content in soil of about 2500 mg/kg, Vetiver grass of 3 months old (from planting time) was recorded to accumulate the highest quantity of lead in its leaves and roots (42.91±1.27 and 865.92±17.67 mg/kg, respectively), resulting in the best ability in term of Pb contaminated removal from the soil (14.23±1.23mg). As a result, the relatively high lead accumulation of Vetiver grass mainly root system, was also reported.

Activation of Durian Skin Biomass with H2SO4 Activator on the Absorption of Lead from its Solution

Research has been carried out on the bioabsorption of lead (Pb) using durian skin biomass (Durio zibethinus) which has been activated using an H2SO4 activator. The durian skin sample used was durian skin from Central Sulawesi. The processing technique to remove lead (Pb) from liquid waste was carried out by an adsorption process. The adsorption process is an effective purification and separation technique used in industry because it is more economical and simple in treating wastewater and is a technique that is often used to reduce metal ions in wastewater. This study aims to determine the mass and contact time of the adsorption of Pb by durian skin biomass. Determination of the adsorbed metal used atomic absorption spectrophotometry (AAS). The results obtained showed that the optimal Pb ion adsorption occurred at a weight of 2.5 grams with an absorption capacity of 99.94 %. While the optimal Pb ion adsorption occurred at a contact time of 40 minutes with an absorption capacity of 99.94 %

Effects of Different Sulfur Compounds on the Distribution Characteristics of Subcellular Lead Content in Arabis alpina L. var. parviflora Franch under Lead Stress.

Sulfur plays a vital role in the phytoremediation of lead-contaminated soil. The effects of different sulfur forms (S Na2S, and Na2SO4) on lead (Pb) absorption in hyperaccumulator Arabis alpina L. var. parviflora Franch were studied in a soil pot experiment. The subcellular sulfur and lead enrichment characteristics in A. alpina were studied by adding sulfur in different forms and concentrations (0, 75, and 150 mg·kg-1) to Pb-contaminated soil. The results show that the root and shoot biomass increased by 1.94 times under Na2S and Na2SO4 treatment, and the root-shoot ratio of A. alpina increased 1.62 times under the three forms of sulfur treatments, compared with the control. Sulfur content in cell walls and soluble fractions of the root and shoot of A. alpina significantly increased 3.35~5.75 times and decreased 5.85 and 9.28 times in the organelles under 150 mg·kg-1 Na2SO4 treatment. Meanwhile, Pb content in the root and shoot cell walls of A. alpina significantly increased by 3.54 and 2.75 times, respectively. Pb content in the shoot soluble fraction increased by 3.46 times, while it significantly reduced by 3.78 times in the shoot organelle. Pb content in the root organelle and soluble fraction decreased by 2.72 and 2.46 times. Different forms and concentrations of sulfur had no regularity in the effect of Pb and sulfur content in the subcellular components of A. alpina, but the bioconcentration and translocation factors of A. alpina increased compared with the control. Under different concentrations of Na2SO4, there was a significant positive correlation between the contents of sulfur and Pb in the subcellular components of the root of A. alpina (p < 0.05). These results indicate that sulfur application can enhance the Pb resistance of A. alpina by strengthening the cell wall fixation and vacuolar compartmentalization.

Direct absorption of atmospheric lead by rapeseed siliques is the leading cause of seed lead pollution.

Rapeseed cultivation is a novel approach to safely utilizing lead (Pb) contaminated farmland. However, the mechanism of Pb absorption in seeds remains uncertain. A field experiment was conducted to explore this mechanism with two contrasting treatments: rapeseed exposed to atmospheric deposition and non-exposed treatment. Non-exposed treatment ultimately decreased Pb content in leaf, silique, and seed by 46.7%, 53.7%, and 53.6%, respectively. Sub-microstructure analysis further confirmed that rapeseed leaves and siliques could directly absorb atmospheric Pb. In addition, Pb isotope analysis indicates that atmospheric deposition is the primary source of silique and seed Pb. The root and silique organs had relative Pb contributions of 28.0% and 72.0%, respectively, to seed. Thus, the direct absorption of atmospheric Pb by siliques during the filling stage was found to be the leading cause of seed Pb pollution.

МЕХАНІЗМ ПРОЦЕСІВ ВСМОКТУВАННЯ КРІЗЬ ШКІРУ ЩУРІВ НАНОЧАСТИНОК СПОЛУК СВИНЦЮ ТА ЗАЛІЗА У ПОРІВНЯЛЬНОМУ АСПЕКТІ ЗА УМОВ ТРИВАЛИХ АПЛІКАЦІЙ

Сomparative study of the mechanism of dermal absorption of lead and iron nanoparticles under long-term exposure of rats: ISSN 2223-6775 Ukrainian journal of occupational health Vol.18, No 4, 2022https://doi.org/10.33573/ujoh2022.04.329 Сomparative study of the mechanism of dermal absorption of lead and iron nanoparticles under long-term exposure of rats Didenko M.M., Melnyk

Lead absorption capacity in different parts of plants and its influencing factors: a systematic review and meta-analysis.

People pose a serious risk by plants contaminated with lead in soil.However, the strength of lead enrichment capacity in root, stem, and leaf of the plant is still controversial. Therefore, a meta-analysis was conducted to investigate the ability of lead enrichment of root, stem, and leaf and the main influencing factors for lead absorption.The results of this study indicated that all parts of plant can significantly accumulate lead. Concentrations of lead followed an order of root > stem > leaf. Alkaline soil was conducive to the absorption of lead. When the lead concentration in the soil was higher than 20mg/kg, the lead absorption in root was more. Lead is absorbed most in trees and least in Gramineae. It is argued that this study is beneficial to select plants suitable for absorption of lead from polluted soil. This study also can help to clarify the influencing factors for lead enrichment in different parts of the plant.

Properties of Concrete with The Inclusion of Ceramic Waste As Coarse Aggregate

Ceramic tile waste, which is obtained from construction sites, demolition sites, and manufacturing industries, has a negative impact on the environment. Recycling these ceramic tiles to produce concrete could be a useful strategy for preserving the environment and enhancing the concrete's inherent qualities. To lessen the impact of waste materials on the environment, this study seeks to ascertain whether it is feasible to substitute waste materials from ceramic tiles as coarse aggregates in the production of concrete. Experimental studies were conducted and the concrete grade 30 was tested for slump test, compression test, and water absorption test, at various curing times of 7, 14, and 28 days. Additional water absorption of the CTA lead to increased water demand, which then increased the levels of porosity and reduced workability. The high porosity of the CTA concrete reduces the density of the concrete and has an impact on compressive strength. CTA has the probability to be used, but precaution needs to be required, especially for higher replacements that may influence the compressive strength and thus partial replacement is suggested.

New Evidence of Semi-Mangrove Plant Barringtonia racemosa in Soil Clean-Up: Tolerance and Absorption of Lead and Cadmium.

Mangrove plants play an important role in the remediation of heavy-metal-contaminated estuarine and coastal areas; Barringtonia racemosa is a typical semi-mangrove plant. However, the effect of heavy metal stress on this plant has not been explored. In this study, tolerance characteristics and the accumulation profile of cadmium (Cd) and lead (Pb) in B. racemosa were evaluated. The results indicated that B. racemosa exhibited a high tolerance in single Cd/Pb and Cd + Pb stress, with a significant increase in biomass yield in all treatment groups, a significant increase in plant height, leaf area, chlorophyll and carotenoid content in most treatment groups and without significant reduction of SOD, POD, MDA, proline content, Chl a, Chl b, Chl a + b, Car, ratio of Chl a:b and ratio of Car:Chl (a + b). Cd and Pb mainly accumulated in the root (≥93.43%) and the content of Cd and Pb in B. racemosa was root > stem > leaf. Pb showed antagonistic effects on the Cd accumulation in the roots and Cd showed antagonistic or synergistic effects on the Pb accumulation in the roots, which depended on the concentration of Cd and Pb. There was a significant synergistic effect of Cd and Pb enrichment under a low Cd and Pb concentration treatment. Thus, phytoremediation could potentially use B. racemosa for Cd and Pb.

Analysis of Organic Flocculants in Lead and Cadmium Biosorption in Laboratory-Level Samples

The intention of the work is to evaluate the absorption of lead and cadmium in water, by means of controlled tests, by means of a protocol based on the preparation of 3 types of concentrations of the indicated metals, in a water sample of 1 liter, the used dose of flocculants was made in 5 groups, with varied times of rest of are from 5 minutes to 30 minutes, the method that is presented to evaluate these concentrations, is characterized in being able to use different concentrations, with situations of controlled environment, the most encouraging result was the one that presents a level of concentration of 2. 5 grams of natural flocculant. In order to eliminate cadmium, we have a better response using flocculants based on coconut, grapefruit, tangerine, cucumber and apple fruits.

Expanding the absorption and photoresponse of 1D lead-halide perovskites via ultrafast charge transfer.

Low-dimensional metal halide perovskites are attracting extensive attention due to their enhanced quantum confinement and stability compared to three-dimensional perovskites. However, low dimensional connectivity in the inorganic frameworks leads to strongly bounded excitons with limited absorption properties, which impedes their application in photovoltaic devices. Here, we show that, by incorporating a strong electron accepting methylviologen cation, charge transfer (CT) at the organic/inorganic interface can effectively tune the optical properties in one-dimensional (1D) lead-halide perovskites. Both 1D MVPb2I6 and MVPb2Br6 display expanded absorption and photoresponse activity compared to CT inactive cations. The photoinduced CT process in MVPb2I6 was further characterized by transient absorption spectroscopy, which shows an ultrafast CT process within 1ps, generating charge separated states. Our work unveils the interesting photophysics of these unconventional 1D perovskites with functional organic chromophores.