Heavy Metal Compounds Research Articles

A histological observation on heavy metal induced implications on respiratory epithelium and its causative impact on a catfish Heteropneustes fossilis (Bloch)

Present study is based on lead nitrate induced histological effect on the respiratory organs of Heteropneustes fossilis (Bloch). Lead nitrate is a heavy metal compound which used in many industries and indiscriminately drains out in water system and contaminates aquatic medium leads serious hazardous effect on respiratory epithelium of fish. Lead nitrate induced alteration on respiratory epithelium associated with the air breathing organ, suprabranchial chamber and air sacs of Heteropneustes fossilis (Bloch) and also affect the oxygen consumption capacity of fish which adversely affect its survival. Heavy metal poisoning produced remarkable histopathological deleterious effect on the accessory respiratory organ decreases the rate of oxygen consumption. Various concentration of lead nitrate showed noticeable histopathological changes which is a sign of serious effect of this heavy metal and its bioaccumulation ultimately dangerous for human consumption of contaminated fish through food chain.

Ameliorative effect of rutecarpine supplementation against cisplatin-induced nephrotoxicity in rats via inhibition of monocyte chemoattractant protein-1, intercellular adhesion molecule-1, high-mobility group box 1, and nuclear factor kappa B.

Cisplatin, the pioneering heavy metal compound, stands out as a potent drug for the treatment of various solid tumors. However, its clinical utility is hampered by notable toxicity and adverse effects, particularly nephrotoxicity. The potency of rutecarpine, a phytochemical, in mitigating cisplatin-induced nephrotoxicity was assessed in the present study. In this experimental setup, healthy male Wistar rats were grouped into four and Group I rats served as the control group, receiving only vehicle control. Group II rats were subjected to cisplatin treatment alone, administered intraperitoneally at a dosage of 7mg/kg body weight on the 19th, 20th, and 21st days. Group III and IV rats were orally administered with rutecarpine at doses of 10 and 20mg/kg body weight, respectively, starting from Day 1 and continuing daily for 21 days. Additionally, they were injected intraperitoneally with cisplatin at the same dosage and schedule as Group II. Relative kidney weight and renal biochemical markers blood urea nitrogen, lactate dehydrogenase, serum urea, and creatinine were measured to assess rutecarpine inhibitory potency against cisplatin toxicity. Markers of oxidative damage and antioxidants levels were quantified in the ruteacarpine- and cisplatin-treated rats. The study investigated the anti-inflammatory property of rutecarpine in cisplatin-induced nephrotoxicity by analyzing inflammatory cytokines. Renal tissue levels of monocyte chemoattractant protein-1, intercellular adhesion molecule-1, high-mobility group box 1, and nuclear factor kappa B, key markers of nephrotoxicity, were quantified to assess rutecarpine's potential to mitigate cisplatin-triggered damage. Histopathological examinations were performed to confirm the impact of rutecarpine against cisplatin-induced nephrotoxicity. Treatment with rutecarpine notably reduced renal biochemical markers, prevented renal edema, and attenuated oxidative stress-induced damage in cisplatin-treated rats. Both inflammatory and nephrotoxicity markers showed significant decreases in rats treated with rutecarpine along with cisplatin. Histological analysis affirmed that rutecarpine pretreatment effectively prevented cisplatin-induced nephrotoxicity. The study findings demonstrate that rutecarpine ameliorates cisplatin-triggered nephrotoxicity through its antioxidant and anti-inflammatory properties, suggesting that rutecarpine supplementation alongside cisplatin treatment could potentially reduce nephrotoxicity in cancer patients.

Hygienic assessment of heavy metal and organic compounds pollution in snow cover of a multi-industrial city

Introduction. One of the leading health risk factors is atmospheric air pollution, the state of which can be indirectly assessed by the content of a wide range of pollutants in snow and soil cover. Materials and methods. The study analyzed data on deposits of polycyclic aromatic compounds (PAHs), heavy metals (HMs) and petroleum hydrocarbons (PHs) in the snow of different functional zones of the agglomeration. Physicochemical research methods were used. Results. The content of ΣPAHs was found to range from 412.8 to 2843.7 ng/L. The highest concentrations of ∑PAHs were observed in the residential area in the square (point 10) – 2843.7 ng/L; and on the border of the sanitary protection and residential zones in the area of the Yuzhnaya station (point 3) – 1758.2 ng/L. The share of benzo(a)pyrene (B(a)P) from ∑PAH ranged from 2.9 to 9.7%. PHs levels ranged from 51.0–117.0 μg/L. The difference in the range of fluctuations in values was most evident in the content of individual PAHs: B(a)P (16.13 times), Ant (12.05 times) and B(g,h,i)P (11.56 times ), mercury (17.53 times), zinc (9 times) and manganese (8.58 times); metals: cadmium (1.89 times), copper (1.75 times), and lead (1.47 times). Limitations. Sampling and features of snow cover contamination by atmospheric precipitation in the dynamics of the winter season. Conclusion. Concentrations of PAHs and HM varied in different ranges of values and had a non-uniform spatial distribution over the territory. Direct links were found between the content of B(a)P and other polyarenes in the snow cover.

Lead (Pb) removal from gold mining-impacted water utilizing palm oil fuel ash (POFA)

Mining, particularly gold mining, is a lucrative industry. However, it poses significant environmental risks, such as releasing heavy metal elements into the soil and water. After gold mines are exhausted, whether they are small or large scale, the excavated sites often need to be repaired. This situation has led to a global concern regarding the presence of heavy metals from mining activities, which are known to be carcinogenic and harmful to living organisms. The concentration of heavy metals in these areas often surpasses safety limits, necessitating advanced treatment methods for their removal, especially lead (Pb) compounds from gold mining waste. One effective treatment method is the adsorption process. This study examined POFA's inherent capacity to remove lead from water contaminated by gold mining without modification. This method was preferred due to its high efficiency and cost-effective option for removing heavy metal compounds. According to the experiment's results, the largest adsorption capacity of 0.816 mg/g was followed by the greatest removal efficiency of 91.837%. The isotherm analysis found that the Langmuir model provided an outstanding fit for the experimental data. Thus, this relationship suggested that on the surface of the POFA, a monolayer and an adsorption process suitable for physical adsorption took place.

PERFORMANCE OF MEDICAL WASTE ASH AS A PAVING BLOCK: IMPACTS TO AIR QUALITY AND HEAVY METALS IN PRODUCT

In compliance with regulation of the Republic of Indonesia 22 of 2021, hazardous and toxic waste (B3) producers are obligated to use B3 waste. The purpose of this research is to assess the influence of using ash from incinerated medical waste on air quality and to identify the concentration of heavy metals in paving block products such that its use is ecologically and environmentally benign. Air quality is measured as dust present in it using the Gravimetry technique while noise was measured using a Sound Level Meter. The Toxicity Characteristic Leaching Procedure (TCLP) was used to determine the level of lead Pb, nickel (Ni), copper (Cu), and cadmium (Cd) compounds in the product. The usage of medical waste ash had an influence on the environment with respect to air quality in the form of dust with a value that exceeds the prescribed quality standard threshold, but noise values on the environment and health can be tolerated. Ash from the burning of medical waste has the potential to be used as paving blocks with a soaking period of between seven and 14 days, with metal levels of Ni, Cu, and Cd well below the quality limits imposed by the government. Unlike the heavy metal compound Pb, above the TCLP B (0.5 mg/l). Medical waste ash has the potential to be used as paving blocks with the addition of a pozzolanic composition so that it can bind the maximum amount to heavy metals.

The promoting effect of Fe on the immobilization of heavy metals in MSWI FA–lead–zinc tailings-based backfill materials under field application: Dynamic simulation leaching and immobilization mechanisms

Currently, research on solid waste-based backfill materials containing municipal solid waste incineration fly ash (MSWI FA) was primarily concentrated at the laboratory stage, with insufficient studies on their leaching safety and heavy metal immobilization mechanisms under field application. This study demonstrated that MLBM (Binder weight ratio: MSWI FA: steel slag (SS): blast furnace slag (BFS): flue gas desulfurized gypsum (FGDG): coal fly ash (CFA) = 10 %:33.6 %:33.6 %:12.8 %:20 %; binder-to-lead–zinc tailings (LZT) ratio was 1:8; mass concentration was 60 %) exhibited excellent leaching safety in actual backfilling. The study found that MLBM posed no risk of heavy metal and anion leaching under various leaching standards. Furthermore, MLBM showed no risk of harmful element leaching within a simulated percolation period of 100 years. The release mechanisms of Pb, As, Zn, and Cr in MLBM were diffusion, diffusion, flushing, and dissolution, respectively. The immobilization efficiency of Pb, Zn, Cr, As, Cl−, and SO42− positively correlated with the pH value (pH>7.5). The immobilization mechanism included: 1) Formation of insoluble heavy metal compounds. In the MLBM system (The pH ranged from 7.89 to 8.87), Fe(III) (Fe(OH)3(aq) and Fe(OH)4−) contributed to the immobilization of Pb2+ and SO42− and oxidized As(III) (H2AsO3−) and Cr(III) (Cr(OH)3(aq)), forming As(V) (HAsO42−) and Cr(VI) (CrO42−), respectively. 2) Adsorption. The negatively charged surface of C–(A)–S–H gel could immobilize Zn2+ and Pb2+ through adsorption, and the ionic forms of Pb(II) and Zn(II) were PbOH+ and ZnOH+, respectively. This study provided theoretical support for the leaching safety and immobilization mechanisms of solid waste-based backfill materials containing MSWI FA in field applications.

REMOVAL OF LEAD IONS BY GREEN SYNTHESIZED SILVER NANOPARTICLES USING AQUEOUS EXTRACTS OF PROSOPIS JULIFLORA AND MENTHA PIPERITA L. LEAVES

Heavy metal compounds are commonly used as required industrial materials. Heavy metal ions are known to possess poisonous properties. Lead (II) ion is one of them; it is more toxic and carcinogenic. The contamination of water with Pb (II) may lead to kill people who drink it, in addition to harmful effects on plants and animals. Therefore, Pb (II) ions must be removed from the polluted water. In this work, an eco-friendly method was employed to synthesize silver nanoparticles (AgNPs) from silver nitrate and two separate plant extracts; leaves of Prosopis Juliflora and Mentha Piperita L. AgNPs were used to remove Pb (II) ions from aqueous solutions through the adsorption process. The synthesized AgNPs were identified by ultraviolet- visible (UV-Vis), Fourier-transform infrared (FTIR), transmission electron microscope (TEM), scanning electron microscope (SEM), and energy-dispersive X-ray spectroscopy (EDS) analysis. The diameters of formation nanoparticles were within the range of 8.06–11.5 and 8.02- 11.5 nm of AgNPs from Prosopis Juliflora, and AgNPs from Mentha Piperita L. extracts, respectively. During the adsorption process, the influence of adsorbent dose, Pb (II) ion concentration, and contact time in removing were studied at constant temperature and constant pH.

Co-pyrolysis of municipal sludge and papermaking sludge: Pyrolysis behaviors and heavy metals immobilizations

The co-pyrolysis of municipal sludge (MS) and papermaking sludge (PS) is beneficial for improving the quality of co-pyrolysis biochar and the stability of heavy metals in it. This study investigated the synergistic effect of co-pyrolysis of MS and PS, as well as the influence of different mass ratios (1:9, 3:7, 5:5, 7:3, and 9:1; MS:PS) and pyrolysis temperatures (400–600 ℃) on the physicochemical properties of pyrolysis char, chemical speciation of heavy metals, and their potential ecological risk index. Furthermore, thermodynamic equilibrium calculations were used to study the transformation and stabilization mechanisms of heavy metals during co-pyrolysis. The results indicated that the addition of PS increased the comprehensive pyrolysis index of MS (by 2.09–16.72 times) and the specific surface area of co-pyrolysis char. The inclusion of MS effectively promoted the transformation of heavy metals from unstable fractions to stable fraction, significantly reducing the potential ecological risk index of pyrolysis biochar (by 21.93–41.58 %). The combination of thermodynamic equilibrium calculations and experimental data demonstrated that heavy metals in sludge could be stabilized through the formation of stable heavy metal compounds or their encapsulation within the lattice of inorganic components during co-pyrolysis. These findings suggest that co-pyrolysis of MS and PS is a feasible and promising approach for producing high-quality pyrolysis char with low risk of heavy metals.

Biosensors in environmental analysis of microplastics and heavy metal compounds – A review on current status and challenges

Biosensors (biological sensors) are a promising alternative to standard analytical techniques for testing and monitoring in the environment, among others, heavy metals. Biological materials that detect heavy metals include enzymes, bacteria, fungi, and plant and animal cells. The paper aimed to evaluate the possibilities of biosensor usage in environmental analysis, considering an easy and environmentally friendly analysis of individual compounds (e.g., heavy metals) or their mixtures in various samples directly in the environment, as well as continuous monitoring of these compounds. The work considers biosensors' characteristics, classification, and operation principles. Attention is paid to the possibility of using bioluminescent bacteria as biological material in a biosensor. Examples of the study of heavy metals using various biological sensors were given. It also indicates the possibility of using biosensors to determine microplastics by applying specific hormones (estrogens) receptor use and peptides as a solution or incorporating them into living microbial cells. Additionally, support was given to the use of biosensors to monitor plastics' degradation in the water environment using recombinant whole-cell microbial biosensors as detectors for plastic monomers such as acrylic acid monomers. The application of the biosensors highlighted in the paper is to shorten the time of toxicity studies by using new indicators or acceptors. However, several challenges must be overcome, such as cell viability and activity. A continuous water-monitoring system that can handle a severely toxic sample has yet to be developed in toxicity monitoring.

Heavy metal particle liftoff and compound droplet formation on a hydrophobic surface

Heavy metal particle liftoff and compound droplet formation on a hydrophobic surface

CHANGES IN THE PIGMENT COMPOSITION OF RHODOPSEUDOMONAS YAVOROVII IMV B-7620 UNDER THE INFLUENCE OF HEAVY METAL SALTS

The aim of the study was to clarify the changes in the pigment composition of Rhodopseudomonas yavorovii IMB B-7620 under the influence of ferric(III) citrate, cobalt(II) chloride, copper(II) chloride and potassium bichromate. Materials and methods. R. yavorovii IMV B-7620 bacteria were grown at + 27 ... + 30 °C for 14 days in ATCC No 1449 medium supplemented with 1.0–12.0 mM ferric(ІІІ) citrate, 1–15 mM cobalt(II) chloride, 0.050–0.500 mM copper(II) chloride, or 0.010–0.045 mM potassium dichromate. The bacterial cells were sedimented, resuspended in acetone, and disintegrated by sonication. The resulting suspension was kept for 24 hours at -20 °C, after which it was centrifuged, and 0.5 ml of supernatant were filtered through membrane filters (pore diameter 0.45 μm). Chromatographic separation of pigments was performed using a high-performance liquid chromatography system. Results. On the 14th day of cultivation under the influence of heavy metal compounds, the qualitative and quantitative changes in the pigment composition in R. yavorovii IMV B-7620 cells occurred. Under the influence of ferric(ІІІ) citrate, cobalt(II) chloride, and potassium dichromate, a decrease in the pigment content in R. yavorovii IMV B-7620 cells was detected. The content of lycopene decreased by 22.1–83.9%, bacteriochlorophyll a – by 33.8–86.0%, compared to the control. Under the influence of copper(II) chloride, not only the pigment content but also the quantity of its isomers increased. Under the influence of the studied metal compounds, a small amount of anhydrorhodovibrin was detected in the cells, whereas it was not detected in the control. Conclusions. Under the influence of heavy metal compounds, changes in the qualitative and quantitative composition of pigments occur in the cells of bacteria R. yavorovii IMV B-7620. Ferric(III) citrate, cobalt(II) chloride and potassium bichromate caused a decrease in the pigment content in R. yavorovii IMV B-7620 cells. Under the influence of copper(II) chloride, not only the content of pigments increased, but also the quantity of their homologues and isomers, in particular lycopene, which can perform a protective function. Under the influence of all the studied metal salts, a small content of anhydrorhodovibrin was detected in the cells, which was not detected in the control. It can also contribute to the protection of cells from stressors.

Changes in Growth and Heavy Metal and Phenolic Compound Accumulation in Buddleja cordata Cell Suspension Culture under Cu, Fe, Mn, and Zn Enrichment.

Buddleja cordata cell suspension cultures could be used as a tool for investigating the capabilities of this species to tolerate heavy metals (HMs) and for assessing the effects of HMs on the accumulation of phenolic compounds in this species. It grows in a wide range of habitats in Mexico, including ultramafic soils, and mobilizes some HMs in the soil. The mobilization of these HMs has been associated with phenolic substances. In addition, this species is used in Mexican traditional medicine. In the present study, a B. cordata cell suspension culture was grown for 18 days in a culture medium enriched with Cu (0.03-0.25 mM), Fe (0.25-1.5 mM), Mn (0.5-3.0 mM), or Zn (0.5-2.0 mM) to determine the effects of these HMs on growth and HM accumulation. We also assessed the effects of the HMs on phenolic compound accumulation after 1 and 18 days of HM exposure. Cells were able to grow at almost all tested HM concentrations and accumulated significant amounts of each HM. The highest accumulation levels were as follows: 1160 mg Cu kg-1, 6845 mg Fe kg-1, 3770 mg Mn kg-1, and 6581 mg Zn kg-1. Phenolic compound accumulation was affected by the HM exposure time and corresponded to each HM and its concentration. Future research should analyze whole plants to determine the capabilities of Buddleja cordata to accumulate abnormally high amounts of HM and to evaluate the physiological impact of changes in the accumulation of phenolic compounds.

Molecular strategies of the pygmy grasshopper Eucriotettix oculatus adapting to long-term heavy metal pollution

To study the heavy metal accumulation and its impact on insect exterior and chromosome morphology, and reveal the molecular mechanism of insects adapting to long-term heavy metal compound pollution habitats, this study, in the Diaojiang river basin, which has been polluted by heavy metals(HMs) for nearly a thousand years, two Eucriotettix oculatus populations was collected from mining and non-mining areas. It was found that the contents of 7 heavy metals (As, Cd, Pb, Zn, Cu, Sn, Sb) in E. oculatus of the mining area were higher than that in the non-mining 1–11 times. The analysis of morphology shows that the external morphology, the hind wing type and the chromosomal morphology of E. oculatus are significant differences between the two populations. Based on the heavy metal accumulation，morphological change, and stable population density, it is inferred that the mining area population has been affected by heavy metals and has adapted to the environment of heavy metals pollution. Then, by analyzing the transcriptome of the two populations, it was found that the digestion, immunity, excretion, endocrine, nerve, circulation, reproductive and other systems and lysosomes, endoplasmic reticulum and other cell structure-related gene expression were suppressed. This shows that the functions of the above-mentioned related systems of E. oculatus are inhibited by heavy metal stress. However, it has also been found that through the significant up-regulation of genes related to the above system, such as ATP2B, pepsin A, ubiquitin, AQP1, ACOX, ATPeV0A, SEC61A, CANX, ALDH7A1, DLD, aceE, Hsp40, and catalase, etc., and the down-regulation of MAPK signalling pathway genes, can enhanced nutrient absorption, improve energy metabolism, repair damaged cells and degrade abnormal proteins, maintain the stability of cells and systems, and resist heavy metal damage so that E. oculatus can adapt to the environment of heavy metal pollution for a long time.

Mitigating ash-related alkali and heavy metals emissions in rotary kiln through oxygen-carrier-aided combustion of waste

Rotary kiln (RK) incineration technology gains prominence in waste management, aiming to reduce pollution, recover energy, and minimize waste. Oxygen-carrier (OC)-aided incineration of waste in the RK demonstrates notable benefits by enhancing oxygen distribution uniformity and facilitating fuel conversion. However, the effects of OC on ash-related alkali and heavy metals during waste incineration in the RK remain unknown. In this study, manganese ore and ilmenite as OCs are introduced into RK during waste combustion, focusing on their effects on the bottom ashes and the behavior of alkali and heavy metals. Results show that manganese ore exhibits a decreasing reactivity due to oxygen depletion during the conversion from Mn2O3 to Mn3O4, while ilmenite maintains good reactivity due to sustained enrichment of Fe2O3 on the particles even after multiple cycles in RK. The porous structure on the surface of OCs particles verifies the cyclic reaction involving oxidation by air and reduction by fuel as OCs move between the active and passive layers of the bed. The porous OCs particles offer abundant adsorption sites for K from the gaseous phase, with surface-deposited K migrating into the particles and enhancing the OCs' capacity for K adsorption. Adding OCs promotes the formation of stable, less volatile compounds of heavy metals (As, Cr, Pb, and Zn) and enhances their retention in bottom ash while ensuring the leaching toxicity remains below Chinese national standard limits. This study enhances the understanding of OCs in incineration, guiding vital references for waste management practices and environmental sustainability.

An Analysis of Cancer causing Substances and its Impact on Prevalence of Cancer Cases among General Population residing along Thamirabharani River Basin – Evidence based research

As water quality degradation worsens in many countries, economic growth is stunted, health conditions worsen, food production is reduced, and poverty is exacerbated. The aim is to study the quantified levels of carcinogens in the environment, according to IARC Classification such as Arsenic, Cadmium, Chromium, Nickel, Lead, Nitrite/Nitrate and Phosphates and its correlation with spurts of cancer cases across certain sites that lie along Thamirabharani river basin, Tamil Nadu, India. A Systematic literature review for cross-sectional studies that provided information about the groundwater quality was carried out using six databases, "Researchgate, PubMed, Elsevier science direct, Wiley Online Library, Medline and Springerlink" from 2005 to 2021. TNCRP 2021 was taken as a reference to analyze the percentage of all types of cancer cases reported in the districts that lie along the river basin. Quality assessment was done using Newcastle Ottawa Scale. The results show the presence of high concentration of carcinogens in the groundwater and sediments collected near the industries, agricultural land and municipal sewage yard. The significant association between exceeding of the permissible limit of various heavy metal elements and compounds and percentage of cancer cases at that particular site is established in this study. Oral findings commonly associated with chronic toxicity of carcinogenic heavy metals are listed which serves as an alarming signal to adapt to healthy lifestyle and dietary modifications as required.

Environmentally safe technology of waste processing of galvanic production

It is known that waste is difficult to purify using existing reagent methods to the standards of the MPC. In addition, the formed sediments contain poorly soluble hydroxy compounds of heavy metals and gypsum, which makes it impossible to dispose of iron- and copper-containing electroplating sludges. The purpose of the study was to study the possibility of ion exchange separate and simultaneous extraction of iron and copper ions from acidic solutions of pickling and copper plating in galvanic production to obtain ferrites. In the course of research, the highly acidic cation exchange resin Dowex HCR S/S in the H+ form was chosen as the cationite. The choice of a strongly acidic cationite is justified, based on the fact that cationites of this type are able to easily lose hydrogen ions due to their displacement from the cationite matrix by other cations of the solution. The sorption processes of iron (II) and copper (II) ions were carried out under dynamic conditions. In the course of experimental studies, it was shown that with an increase in the concentration of sulfuric acid, the full exchangeable dynamic capacity of the cationite significantly decreases both during the sorption of iron ions and during the sorption of copper ions. For iron-containing solutions, full dynamic exchange capacity decreases from 1.39 g-eq/dm3 in the absence of H2SO4 in the initial solution and decreases to 0.3-0.46 g-eq/dm3 at a concentration of sulfuric acid at the level of 1-3 g/dm3. An increase in the concentration of iron (II) ions leads to a significant increase in full dynamic exchange capacity, even with a concentration of sulfuric acid of 8 - 13 g/dm3, full dynamic exchange capacity was at the level of 1.35 g-eq/dm3, which corresponds to the level of sorption of diluted solutions even in the absence of acid. However, the total concentration shows that the efficiency of sorption of metals from acidic solutions remains quite high and increases with the increase of the initial total content of sorbed ions. The main indicator used when choosing an ion exchange method is the possibility of effective regeneration of the cation exchange material. When using 5% solution of sulfuric acid already at the specific consumption of the regeneration solution, it was possible to achieve a degree of regeneration at the level of 95-98%, and when using 10% solution, the degree of regeneration reached 100%. According to the developed technological scheme, regeneration solutions are processed by precipitation into magnetite in a ferritizer reactor. To remove iron ions from concentrated iron-containing regeneration solutions by the ferrite method in order to obtain ferrite particles (magnetite) with maximum magnetic properties, a mixture of Fe (II) and Fe (III) sulfates was used with their concentration ratio K = [Fe2+]/[Fe3+] = 0.5, as a stable relationship between magnetic properties and sediment volume was noted. At maximum magnetic properties, the sediment volume is minimal, and vice versa. Obtaining highly dispersed magnetic particles from a mixture of ferric and ferric sulfates by precipitating them with 10% NaOH solution during heating allows to significantly reduce the duration of the process, simplify it and increase the productivity of the equipment. To obtain magnetic particles of copper ferrites from regeneration solutions by precipitation with alkali at normal temperatures, the concentration ratio K1 = [Fe2+]/[Cu2+] = 3.15-7.76 should be maintained. With an increase in the concentration of Cu2+ ions, there is an increase in the period of crystallization of the obtained sediments and their acquisition of magnetic properties. The formed ferrite material can be used for environmental purposes as a valuable raw material for carbon monoxide neutralization catalysts, as part of alkaline cement for concrete products, or sent for safe disposal. The obtained results on the application of ion-exchange extraction of iron and copper ions from acidic solutions of galvanic production are expedient as the first stage of complex ecologically safe processing of galvanic wastes with the production of ferritic materials for industrial use.

Migration Behaviour of the Combined Pollutants of Cadmium and 2,2′,4,4′,5,5′-Hexabrominated Diphenyl Ether (BDE-153) in Amaranthus mangostanus L. and Their Toxicity to A. mangostanus

The effects of different concentrations of cadmium and 2,2′,4,4′,5,5′-hexabrominated diphenyl ether (BDE-153) on the growth and related physiological and biochemical indexes of Amaranthus mangostanus L. (amaranth) were studied. The results showed that the presence of BDE-153 promoted the absorption of Cd by the amaranth and inhibited the migration of Cd from the roots to the shoots. At the same time, 0.1 mg/L of Cd had a synergistic effect on the migration of BDE-153, but 5 mg/L Cd inhibited the accumulation of BDE-153 in the aboveground part of the amaranth. In addition, the kinetics of the uptake of pollutants by the amaranth showed that both Cd and BDE-153 could be transported by amaranth, but Cd and BDE-153 were mainly enriched in the roots, and the presence of Cd may cause a lag in the uptake of BDE-153 in the shoots. Compared with the control group, the biomass of the amaranth affected by BDE-153 and a high concentration of Cd (5 mg/L) decreased by 30.2–49.5%, the chlorophyll content decreased by 43.0–60.3%, the Evans blue increased, and the MDA content was higher. The activities of superoxide dismutase (SOD) and catalase (CAT) also decreased with an increase in the BDE-153 concentration. This indicates that the interaction between BDE-153 and a high concentration of Cd (5 mg/L) is more toxic to amaranth than single Cd pollution. This paper provides the necessary data support for phytoremediation of heavy metal and organic compound pollution.

Increasing the Efficiency of Wastewater Treatment from Galvanic Production Using Titanium-containing Coagulants and Membrane Treatment

It has been stated that the use of complex titanium-containing agents can significantly increase the efficiency of wastewater treatment and achieve a reduction in residual concentrations of heavy metal compounds down to standard values. For further separation of coagulated sludge from purified water, it is proposed to use filtration methods with ceramic tubular filters. A significant increase in the filtration rate of titanium-containing coagulation sludge has been confirmed, leading to an increase in the productivity of treatment equipment by 20–30 %. It is recommended for purification of acid-base and chromium-containing wastewater to combine the process of coagulation of impurities by treating the wastewater with a complex titanium-containing coagulant, followed by filtering the resulting sludge using special ceramic tubular filters.

Content of heavy metals in bottom sediments of drained Kakhovka Reservoir

The article highlights the ecological danger of the destruction of the Kakhovka HPP dam and the draining of the Kakhovka Reservoir. The results of experimental studies of the content of mobile compounds and gross forms of heavy metals in five samples of bottom sediments taken from the bottom of drained reservoirs taken on the territory of the Kushugum community of the Zaporizhia district of the Zaporizhia region. Two samples were taken from the bottom of the former flood zone (Balabyne village), 2 samples — from the bottom of the former limestone quarry, which was connected to the floodplain of the Dnipro (Kushugum village) and 1 sample taken from the open area of the Kakhovka Reservoir (Malokaterynivka village). Based on the results of the research, it was established that the maximum permissible limit (for soil) of mobile compounds of lead (from 2.0 to 4.1 times), zinc (from 2.4 to 5.4 times), cadmium (from 1.9 to 2.5 times) was exceeded. and nickel (from 1.04 to 2.2 times) in all investigated bottom sediment samples. Exceeding the MPC (soil) for the content of gross forms of lead was found in five bottom sediment samples (from 1.1 to 1.5 times). Exceedings of the MPC of the soil by the content of gross forms of cadmium and manganese and mobile compounds of copper, nickel, cobalt and manganese were not detected. The maximum limit for the content of mobile compounds of iron and gross forms of zinc, copper, nickel, cobalt and iron is not regulated. The highest degree of contamination of bottom sediments by the content of: mobile compounds and gross forms of lead and nickel was found in samples taken from the bottom of a former limestone quarry (Kushugum village, Zaporizhzhia region); zinc — in a sample taken from the bottom of the former flood zone in the territory of the town of Balabyne and a sample taken from the open area of the Kakhovka Reservoir in the territory of the town of Malokaterynivka; cadmium — in the samples taken from the bottom of the former limestone quarry in the territory of the town of Balabyne and the sample taken from the open area of the Kakhovka Reservoir in the territory of the town of Malokaterynivka. According to the results of the correlation analysis, an extremely strong dependence was established between the content of mobile compounds of heavy metals and their gross forms — for cobalt (r=0.96), cadmium (r=0.92), nickel (r=0.91), lead (r=0.88) and zinc (r=0.84).

In Vitro Toxicity Screening of Fifty Complex Mixtures in HepG2 Cells.

To develop the risk prediction technology for mixture toxicity, a reliable and extensive dataset of experimental results is required. However, most published literature only provides data on combinations containing two or three substances, resulting in a limited dataset for predicting the toxicity of complex mixtures. Complex mixtures may have different mode of actions (MoAs) due to their varied composition, posing difficulty in the prediction using conventional toxicity prediction models, such as the concentration addition (CA) and independent action (IA) models. The aim of this study was to generate an experimental dataset comprising complex mixtures. To identify the target complex mixtures, we referred to the findings of the HBM4EU project. We identified three groups of seven to ten components that were commonly detected together in human bodies, namely environmental phenols, perfluorinated compounds, and heavy metal compounds, assuming these chemicals to have different MoAs. In addition, a separate mixture was added consisting of seven organophosphate flame retardants (OPFRs), which may have similar chemical structures. All target substances were tested for cytotoxicity using HepG2 cell lines, and subsequently 50 different complex mixtures were randomly generated with equitoxic mixtures of EC10 levels. To determine the interaction effect, we calculated the model deviation ratio (MDR) by comparing the observed EC10 with the predicted EC10 from the CA model, then categorized three types of interactions: antagonism, additivity, and synergism. Dose-response curves and EC values were calculated for all complex mixtures. Out of 50 mixtures, none demonstrated synergism, while six mixtures exhibited an antagonistic effect. The remaining mixtures exhibited additivity with MDRs ranging from 0.50 to 1.34. Our experimental data have been formatted to and constructed for the database. They will be utilized for further research aimed at developing the combined CA/IA approaches to support mixture risk assessment.