High Concentrations Of Heavy Metals Research Articles

Seasonal Variations of copper and lead bio-accumulation in two fish species: Mullus barbatus and Siganus rivulatus in the southern part of the Syrian Coast

Seasonal variations in the concentrations of two heavy metals: copper (Cu) and lead (Pb) were determined in the liver and muscles of Mullus the two species barbatus and Siganus rivulatus fish from the southern part of Syrian Coast. The average concentrations of the metals in the fish tissues exhibited the following order: Cu>Pb. The statistical analysis revealed a significant seasonal effect P≤0.05 for Cu and Pb measured. The highest values of the metals were recorded in dry season. The highest concentrations of heavy metals were found in liver tissue of both fish species, while the lowest concentrations were recorded in muscles tissue. The values of the metals detected in the fish muscles (the edible part) were within the permissible limits

Heavy Metal Transport in Different Drip-Irrigated Soil Types with Potato Crop

Heavy metal (HM)-polluted soil is a serious concern, especially as brackish water is widely used for irrigation purposes in water-scarce countries. In this study, the HYDRUS-2D model was used to simulate HM (copper (Cu), lead (Pb), and zinc (Zn)) transport through agricultural land cultivated with potato crops under surface drip irrigation to explore the potential groundwater contamination risk. Three soil types, namely, silty clay loam, sandy loam, and sandy soil, and two irrigation schemes, irrigation every two days (scheme A) and irrigation every four days (scheme B), were considered during the simulations. Firstly, the ability of HYDRUS-2D to simulate water flow was validated using data obtained from a full growing season of the potato crop in a lysimeter irrigated by surface drip irrigation using El-Salam Canal water, Egypt (i.e., water contaminated by HMs). Secondly, the model was calibrated for solute transport parameters. After that, the investigated simulation scenarios were executed. The results showed that HYDRUS-2D effectively simulated water flow. Moreover, a good agreement between the simulations and experimental results of HM concentrations under the calibrated solute parameters was obtained with R2 values of 0.99, 0.91, and 0.71 for Cu, Pb, and Zn concentrations, respectively. HM distribution is considerably influenced by the HMs’ adsorption isotherm. The results of the investigated scenarios reveal that soil texture has a greater impact on HM concentrations in the simulation domain and on the contamination risk of the groundwater than the irrigation scheme. Under both irrigation schemes, lower HM concentrations were observed in sand, while higher values were observed in silty clay loam. Subsequently, the potential shallow groundwater contamination risk is greater when cultivating potatoes in sand, as higher HM concentrations were found in drainage water compared to the two other investigated soils, regardless of the irrigation scheme. The cumulative Cu, Pb, and Zn concentrations in drainage water corresponding to scheme A for silty clay loam and sandy loam were 1.65, 1.67, and 1.67 and 1.15, 1.14, and 1.15 times higher, respectively, than scheme B. To safeguard the sustainability of groundwater and agricultural lands irrigated with water contaminated by HMs, it is recommended to adopt an irrigation frequency of once every four days in soils with silty clay loam and sandy loam textures.

The interaction of different chlorine-based additives with swine manure during pyrolysis: Effects on biochar properties and heavy metal volatilization

Poor properties and high concentrations of heavy metals are still major concerns of successful application of animal manure-derived biochar into the environment. This work thus proposed to add chlorine-based additives (Cl-additives, i.e., CaCl2, MgCl2, KCl, NaCl, and PVC, 50 g Cl/ kg) to improve biochar properties and enhance heavy metal volatilization during swine manure pyrolysis. The results showed that the addition of CaCl2 could improve the retention of carbon (C) by up to 13.1% during pyrolysis, whereas other Cl-additives had little effect on it. Moreover, CaCl2 could enhance the aromaticity of biochar, as indicated by lower H/C ratio than raw biochar. Pretreatment with CaCl2, MgCl2 and PVC reduced phosphorus (P) solubility but increased its bioavailability via the formation of chlorapatite (Ca5(PO4)3Cl). The CaCl2 was more effective for enhancing the volatilization efficiency of heavy metals than other Cl-additives, except for Pb that tended to react with the generated Ca5(PO4)3Cl to form more stable and less volatile Pb5(PO4)3Cl. However, high pyrolysis temperature (900℃) was essential for CaCl2 to simultaneously decrease the bioavailability of heavy metals. Our results indicated that co-pyrolysis of swine manure with CaCl2 is a promising strategy to increase C retention, P bioavailability, and volatilization of heavy metals, and, at higher temperature, reduce the bioavailability of biochar-born heavy metals.

Genome Sequence of a Heavy Metal-Detoxifying Actinomycete, Microbacterium proteolyticum ustc.

A complete genome is presented for Microbacterium proteolyticum ustc, a member of the Gram-positive order Micrococcales of the phylum Actinomycetota that is resistant to high concentrations of heavy metals and participates in metal detoxification. The genome consists of one plasmid and one chromosome.

Geochemical fingerprint and heavy metals assimilation on grapes from south Lessini (Italy)

ABSTRACT Geochemical fingerprints of grape samples have been defined for 10 cultivars grown in two sampling areas characterized by homogeneous pedological and climate systems in the province of Treviso (northeast Italy). The choice of lithologies was based on the fact that vineyards in Italy frequently grow in both sedimentary soils with various terrigenous carbonate contents and basic volcanic soils. The latter may have high concentrations of heavy metals that are essential for a balanced human diet but can be toxic or harmful if assimilated in excess. To identify possible geochemical tracers within the soil that can be passed to the grapes and possible bioaccumulation of soil-derived elements within the grapes, major and trace elements of the soils, sampled at depths of greater root development, were determined by X-ray fluorescence, and metal concentrations in grape juice were determined by inductively coupled plasma-mass spectrometry. All samples were compared with samples collected at two other sites located in the Euganean Hills, in the southern part of the Veneto region, considering that the wines produced in these areas are exported all over the world.

PHYSICOCHEMICAL ANALYSIS AND HEAVY METAL ASSESSMENT OF SACHET WATER SOLD IN GASHUA METROPOLIS OF YOBE STATE, NIGERIA

This study aims at assessing the quality of sachet water sold in Gashua, Bade L.G.A. of Yobe State, Nigeria. Sachet water were obtained from five different factories, named: A, B, C, D and E. Heavy metals’ concentrations were analysed using Atomic Absorption Spectrophotometry and standard analytical procedures were used to assay for the physicochemical parameters. The results obtained from this study revealed that the concentrations of lead (0.12± 0.01, 0.12± 0.01, 0.18± 0.01, 0.05± 0.01 and 0.13± 0.01), cadmium (0.01±0.01, 0.02±0.01, 0.02±0.01, 0.03±0.01, 0.03±0.01) and arsenic (0.11±0.00, 0.14±0.01, 0.22±0.00, 0.09±0.01, 0.13±0.01) for samples A, B, C, D and E were significantly higher than the WHO permissible values of 0.02+0.00, 0.003+0.00 and 0.01±0.00 respectively. Zinc was not detected in any of the samples but iron was detected at significantly lower value of 0.002±0.00, 0.03±0.01, 0.05±0.01, 0.03±0.00 and 0.03±0.00 for samples of A, B, C, D and E respectively, when compared with the WHO standard value of 3.00±0.00. Chromium showed higher concentration in samples A, C and E but samples B and C fall within the WHO permissible limit of 0.05±0.00. Conductivity, TDS and sulphate for samples A, B, C, D and E were seen to be significantly lower than the WHO standard value. Turbidity and total suspended solids were found to be above the WHO limit. In conclusion, the results of this study have shown that some metals of the various branded sachet water do not meet the recommended standard due to high concentration of heavy metals and physicochemical parameters beyond...

Green Synthesis of the Effectively Environmentally Safe Metakaolin-Based Geopolymer for the Removal of Hazardous Industrial Wastes Using Two Different Methods.

Untreated wastewater pollution causes environmental degradation, health issues, and ecosystem disruption. Geopolymers offer sustainable, eco-friendly alternatives to traditional cement-based materials for wastewater solidification and removal. In this study, we investigate how wastewater containing organic and inorganic pollutants can be removed using geopolymer mixes based on metakaolin incorporation with cement kiln dust as an eco-friendly material. The present investigation compares the efficacy of two different techniques (solidification and adsorption) for reducing dye contaminants and heavy metals from wastewater using a geopolymer based on metakaolin incorporation with cement kiln dust. This study investigated the adsorption capacity of a geopolymer based on metakaolin incorporating two different ratios (20% and 40% by weight) of cement kiln dust (MC1 and MC2) for the reactive black 5 dyeing bath effluent (RBD) only and in a combination of 1200 mg/L of Pb2+ and Cd2+, each separately, in aqueous solutions under different adsorption parameters. The results of the adsorption technique for the two prepared geopolymer mixes, MC1 and MC2, show that MC1 has a higher adsorption activity than MC2 toward the reactive black 5 dyeing bath effluent both alone and in combination with Pb2+ and Cd2+ ions separately. The study also looked at using MC1 mix to stabilize and solidify both the dyeing bath effluent alone and its combination with 1200 mg/L of each heavy metal individually inside the geopolymer matrix for different time intervals up to 60 days of water curing at room temperature. The geopolymer matrix formed during the process was analyzed using FTIR, SEM, and XRD techniques to examine the phases of hydration products formed. The results showed that MC1 effectively adsorbs, stabilizes, and solidifies the dying bath effluent for up to 60 days, even with high heavy metal concentrations. On the other hand, geopolymer mixes showed an increase in mechanical properties when hydration time was increased to 60 days. According to our findings, the type of geopolymer developed from metakaolin and 20 wt.% cement kiln dust has the potential to be employed in the treatment of wastewater because it has good adsorption and solidification activity for the reactive black 5 dye effluent alone and for a mixture of dye pollutants with both Pb2+ and Cd2+ ions separately. Our results have significant implications for wastewater treatment and environmental remediation efforts, as they offer a sustainable solution for managing hazardous waste materials.

Removal of arsenic from acidic liquors using chemical and autotrophic and mixed heterotrophic bacteria-produced biogenic schwertmannites

Arsenic penetrates human society through a variety of geological and anthropogenic processes, posing significant health hazards. Acid mine drainage, which contains high concentrations of heavy metals and sulfate, is formed by the biological oxidation of pyrite and other metal-containing sulfidic minerals and is a significant environmental hazard. Adsorption is a simple and effective method for removing arsenic from water. In this study, co-precipitation and adsorption of arsenic with biogenic and chemically produced iron-containing settleable precipitates, i.e. schwertmannites were studied. Autotrophic Leptospirillum ferrooxidans and heterotrophic mixed culture of Alicyclobacillus tolerans and Acidiphilium cryptum oxidized iron at rates from 18 to 23 mg/(L.h) in the presence of 5 and 10 mg/L As3+, and both cultures tolerated up to 100 mg As3+/L although Fe2+ oxidation rates decreased to 3–4 mg/(L.h). At Fe/As ratios of ≥20, As removal efficiencies of ≥95% were obtained by co-precipitation with Fe3+ at pH 3.5–4.5. Because schwertmannite precipitates produced by the heterotrophic culture formed crystals, it was studied for adsorptive removals of As3+ and As5+ and compared with chemically synthesized schwertmannites. As3+ (100 mg/L) adsorption onto biogenic and chemical schwertmannite were 25 and 44%, respectively, at pH 4. At 100 mg As5+/L, adsorption capacity and efficiency onto biogenic schwertmannite were 47 mg/g and 50%, respectively. At 300 mg As5+/L, adsorption capacity and efficiency onto chemical schwertmannite were 169 mg/g and 56%, respectively. In summary, biogenic schwertmannite has potential for As removal via co-precipitation with Fe3+ at pH 3.5–4.5 and Fe/As ratios of ≥20 due to low production cost from acidic mine drainage. In contrast to the schwertmannite generation methods, which are usually performed with autotrophic acidophilic bacteria in the literature, this efficient and modular schwertmannite production process and its evaluation on arsenic adsorption is an important potential in acidic mine drainage treatment containing arsenic.

Effect of heavy metals on the energy metabolism in the brackish water flea Diaphanosoma celebensis

Heavy metals such as lead (Pb), cadmium (Cd), and arsenic (As) are of great concern in aquatic ecosystems because of their global distribution, persistence, and biomagnification via the food web. They can induce the expression of cellular protective systems (e.g., detoxification enzymes and antioxidant enzymes) to protect organisms from oxidative stress, which is a high-energy-consuming process. Thus, energy reserves (e.g., glycogen, lipids, and proteins) are utilized to maintain metabolic homeostasis. Although a few studies have suggested that heavy metal stress can modulate the metabolic cycle in crustaceans, information on changes in energy metabolism under metal pollution remains lacking in planktonic crustaceans. In the present study, the activity of digestive enzymes (amylase, trypsin, and lipase) and the contents of energy storage molecules (glycogen, lipid, and protein) were examined in the brackish water flea Diaphanosoma celebensis exposed to Cd, Pb, and As for 48 h. Transcriptional modulation of the three AMP-activated protein kinase (AMPK) and metabolic pathway-related genes was further investigated. Amylase activity was highly increased in all heavy metal-exposed groups, whereas trypsin activity was reduced in Cd- and As-exposed groups. While glycogen content was increased in all exposed groups in a concentration-dependent manner, lipid content was reduced at higher concentrations of heavy metals. The expression of AMPKs and metabolic pathway-related genes was distinct among heavy metals. In particular, Cd activated the transcription of AMPK-, glucose/lipid metabolism-, and protein synthesis-related genes. Our findings indicate that Cd can disrupt energy metabolism, and may be a potent metabolic toxicant in D. celebensis. This study provides insights into the molecular mode of action of heavy metal pollution on the energy metabolism in planktonic crustaceans.

Isolation and Identification of Arsenic-Resistant Extremophilic Bacteria from the Crater-Lake Volcano "El Chichon", Mexico.

The crater lake at "El Chichón" volcano is an extreme acid-thermal environment with high concentrations of heavy metals. In this study, two bacterial strains with the ability to resist high concentrations of arsenic (As) were isolated from water samples from the crater lake. Staphylococcus ARSC1-P and Stenotrophomonas ARSC2-V isolates were identified by use of the 16S rDNA gene. Staphylococcus ARSC1-P was able to grow in 400mM of arsenate [As(V)] under oxic and anoxic conditions. The IC50 values were 36 and 382mM for oxic and anoxic conditions, respectively. For its part, Stenotrophomonas ARSC2-V showed IC50 values of 110mM and 2.15 for As(V) and arsenite [As(III)], respectively. Arsenic accumulated intracellularly in both species [11-25nmol As × mg cellular prot-1 in cells cultured in 50mM As(V)]. The present study shows evidence of microbes that can potentially be a resource for the bio-treatment of arsenic in contaminated sites, which highlights the importance of the "El Chichón" volcano as a source of bacterial strains that are adaptable to extreme conditions.

Stress of cupric ion and oxytetracycline in Chlorella vulgaris cultured in swine wastewater

Chlorella culturing has the advantages in treatment of wastewater including swine wastewater from anaerobic digesters due to the product of biolipids and the uptake of carbon dioxide. However, there often exist high concentrations of antibiotics and heavy metals in swine wastewater which could be toxic to chlorella and harmful to the biological systems. This study examined the stress of cupric ion and oxytetracycline (OTC) at various concentrations on the nutrient removal and biomass growth in Chlorella vulgaris culturing in swine wastewater from anaerobic digesters, and its biochemical responses were also studied. Results showed that dynamic hormesis of either OTC concentration or cupric ion one on Chlorella vulgaris were confirmed separately, and the presence of OTC not only did not limit biomass growth and lipids content of Chlorella vulgaris but also could mitigate the toxicity of cupric ion on Chlorella vulgaris in combined stress of Cu2+ and OTC. Extracellular polymeric substances (EPS) of Chlorella vulgaris were used to explain the mechanisms of stress for the first time. The content of proteins and carbohydrates in EPS increased, and the fluorescence spectrum intensity of tightly-bound EPS (TB-EPS) of Chlorella vulgaris decreased with increasing concentration of stress because Cu2+ and OTC may be chelated with proteins of TB-EPS to form non-fluorescent characteristic chelates. The low concentration of Cu2+ (≤1.0 mg/L) could enhance the protein content and promote the activity of superoxide dismutase (SOD) while these parameters were decreased drastically under 2.0 mg/L of Cu2+. The activity of adenosine triphosphatase (ATPase) and glutathione (GSH) enhanced with the increase of OTC concentration under combined stress. This study helps to comprehend the impact mechanisms of stress on Chlorella vulgaris and provides a novel strategy to improve the stability of microalgae systems for wastewater treatment.

Distribution Characteristics of Heavy Metals in Different Particle Size Fractions of Chinese Paddy Soil Aggregates

In recent years, the migration and transformation of heavy metals (HMs) in soil has become a hot issue. Soil particle size has an important effect on the environmental behavior of HMs in soil. The distribution of HMs in soil is strongly affected by the size of a soil aggregate. In this study, paddy samples in both cultivated and uncultivated soils were collected from Anhui Province, China. The soils were sieved into six particle size fractions (diameters of >4000, 4000–2000, 2000–1000, 1000–250, 250–53, and <53 μm) and the wet digestion method was used to determine the concentrations of Cd, Cr, Pb, and As in the soil aggregates. The results showed that the surface soils were characterized by the largest proportion of coarsest aggregates of >4000 μm particles. Moreover, the concentrations of Cd, Cr, Pb, and As were elevated in cultivated paddy soils compared to uncultivated soils. The accumulation of HMs in all paddy soils increased with decreasing particle size. Although the smallest particle size fractions accounted for only 5.65–17.28%, they provided the highest distribution factor (DF) of Cr (1.35), As (1.25), Cd (1.28), and Pb (1.38). The highest contributions of HMs came from the coarser fractions (>2000 μm); however, for Cr, Pb, Cd, and As, the mass loading of <53 μm particles was up to 15.90%, 14.41%, 15.21%, and 15.70%, respectively. The highest content of HMs was found in the finest aggregate, with a pattern of decreasing with increasing aggregate size. In addition, the leachability behaviors of different HMs in different particle size aggregates were different. The leachability behaviors of Cr and Pb in the coarse particle size fractions were the highest, while the leachability behaviors of As and Cd in the less than 250 μm particle size fractions were 10–100 times higher than those of Cr and Pb. A correlation analysis showed that the particle distributions of Fe, TOC, and Mn had significant influences on the distributions of Pb, Cd, As, and Cr. This study provides a theoretical basis for the prevention, treatment, and remediation of HMs pollution in soil.

Medical waste management in Al-Kut City

This research investigates solid waste management in Al-Kut City. It included the collection of medical and general solid waste generated in five hospitals different in their specialization and capacity through one week, starting from 03/02/2012. Samples were collected and analyzed periodically to find their generation rate, composition, and physical properties. Analysis results indicated that generation rate ranged between (1102 – 212) kg / bed / day, moisture content and density were (19.0 % - 197 kg/ m3) respectively for medical waste and (41%-255 kg/ m3) respectively for general waste. Theoretically, medical solid waste generated in Al-Kut City (like any other city), affected by capacity, number of patients in a day, and hospital specialty The research exposed the incorrect ways used in collecting, storing, waste transport, and inefficient incinerators processing .Laboratory test for six ash collected samples indicated high concentration of heavy metals (Pb, Cd, Cr) , having the rang of (51.0 – 62.0) mg / l of lead, (3.0 – 8.5) mg / l for cadmium, and (43.0 -69.0) mg / l for chrome. In comparison with the US Environmental Protection Agency standards, these samples are higher than the recommended levels that may threat groundwater. A comprehensive and integrated solution there must be to manage medical waste, with the participation of all parties concerned, especially, the Ministry of Health, environment authorities concerned, and the participation of civil society organizations. A color-code trash bags and containers are recommended by the World Health Organization and the Environmental Protection Agency to be used in hospitals that propose red bags for collecting medical waste while black bags for general waste provided that they are resistant to tearing seeping and should be provided in sufficient numbers.

Glass recovery and production of manufactured aggregate from MSWI bottom ashes from fluidized bed and grate incineration by means of enhanced treatment

Enhanced treatment of incineration bottom ashes (IBA) from municipal solid waste incineration can contribute to a circular economy since not only metals can be recovered but also glass for recycling. Moreover, the remaining mineral fraction can be utilized in concrete as manufactured aggregate. To evaluate the effects of an enhanced treatment, three IBAs from fluidized bed combustion (FB-IBAs) and three grate incineration bottom ashes (G-IBAs) were standardly treated in a jig and further processed on a pilot scale, including improved metal recovery and sensor-based glass separation. The removed glass fractions were weighed and their composition was assessed by means of manual sorting. The manufactured aggregate was also sorted manually and its total and leachate contents were determined before and after aging. Results showed general differences between FB-IBAs and G-IBAs. For G-IBAs, higher contents of heavy metals and residual metal pieces were determined, while the share of glass removed was low compared to FB-IBA. The treated mineral fractions from G-IBA contained more mineral agglomerates, whereas FB-IBAs contained more glass. However, the glass-fractions removed from FB-IBAs need further treatment to be accepted in glass recycling. Austrian limit values for utilization in concrete were met by all manufactured aggregates produced from FB-IBA, but only by one from G-IBA. Overall, the enhanced treatment in the study performed well compared to the literature. Nevertheless, further investigations are necessary to improve the recyclability of the recovered glass fractions and to determine the technical suitability of manufactured aggregates produced from IBAs.

Exploring invertebrate indicators of ecosystem health by focusing on the flow transitional zones in a large, shallow eutrophic lake

The river–lake transitional zone provides a unique environment for the biological community and can reduce pollution inputs in lake ecosystems from their catchments. To explore environmental conditions with high purification potential in Lake Taihu and indicator species, we examined the river-to-lake changes in water and sediment quality and benthic invertebrate communities in the transitional zone of four regions. The spatial variations in the environment and invertebrate community observed in this study followed the previously reported patterns in Taihu; the northern and western regions were characterized by higher nutrient concentrations in water, higher heavy metal concentrations in sediment, and higher total invertebrate density and biomass dominated by pollution-tolerant oligochaetes and chironomids. Although nutrient concentrations were low and transparency was high in the eastern region, the taxon richness was the lowest there, which disagreed with the previous findings and might be due to a poor cover of macrophytes in this study. The river-to-lake change was large in the southern region for water quality and the invertebrate community. Water circulation induced by strong wind-wave actions in the lake sites of the southern region is assumed to have promoted photosynthetic and nutrient uptake activities and favored invertebrates that require well-aerated conditions such as polychaetes and burrowing crustaceans. Invertebrates usually adapted to brackish and saline environments are suggested to be indicators of a well-circulated environment with active biogeochemical processes and a less eutrophic state in Taihu, and wind-wave actions are key to maintaining such a community and natural purifying processes.

Heavy Metals in Fly Ash as a Factor Limiting Its Use in Fertilizing Composts

Composting enables the recycling of significant amounts of biodegradable waste, while ensuring its disposal. The addition of fly ash increases the concentration of fertilizing substances in the compost. Compost is a source of many nutrients for plants. The addition of fly ash might also cause a slower release of these nutrients into an aqueous solution, meeting the fertilization needs of plants over a longer period of time. Tests were carried out using sewage sludge (WWTP Piaseczno, 163,500 P.E.), straw as a structure-forming material and fly ash (WWTP Krakow, 780,000 P.E.). The compost obtained in the research was analyzed in terms of environmental conditions specified in legal regulations. The most favorable compost mass density (520 kg/L) and the amount of air supplied to the process (5.0 L/(h∙kg d.m.)) were determined. The addition of fly ash to the compost mass did not significantly affect the temperature distribution obtained in the process. The increase in fly ash content increased the pH of the compost mass and was associated with higher nitrogen losses. It was found that the factor which may limit the possibility of using fly ash as a compost substrate is the presence of higher concentrations of heavy metals, especially chromium. It was determined that the maximum addition of fly ash to the compost mass was 154 kg d.m.ash/(ton d.m.straw+sludge).

NUTRITIONAL VALUE AND HEAVY METAL CONTENT OF CRAB MEAT AND ITS BYPRODUCT WHITE MUD CRAB Scylla paramamosain

Mud crab is fishery commodity that has high economic value and rich of nutritional aspect such as essential amino acids, vitamins, minerals, and fatty acids. In addition, high concentrations of heavy metals in the natural habitat of crabs can accumulate in these organisms which can endanger health if consumed. However, there is little information regarding the nutritional and heavy metal content of meat and byproducts in mud crab. The objective of the study are to compare the beneficial component of the meat and byproduct of Scylla paramamosain and to investigate food safety from heavy metal contamination. Proximate, vitamin A, D, and E content were analyzed using HPLC, vitamin B1, B2, C, and amino acid profile was determined by using UPLC, vitamin B12 was determined by LC-MS, mineral and heavy metal were determined by standard method of AOAC. In addition, the determination of fatty acid was analyzed by gas chromatography. Result showed that protein per gram as the majority content of each form (10.24% in crab meat and 12.47% in byproduct). Vitamin B2, B12, and E were detected in sample. On contrary, heavy metals examined in this study were not detected. L-Glutamic acid was the most abundant of amino acids composition (11037.79 mg/kg of crab meat and 15993.22 mg/kg of byproduct), while omega-3 fatty acids, omega-6 fatty acids, and omega-9 fatty acids are also contained in this species. The result showed Scylla paramamosain as source of beneficial food and safe to consume.

Resourceful Treatment of Battery Recycling Wastewater Containing H2SO4 and NiSO4 by Diffusion Dialysis and Electrodialysis

Facing the increasing demand for batteries worldwide, recycling waste lithium batteries has become one of the important ways to address the problem. However, this process generates a large amount of wastewater which contains high concentration of heavy metals and acids. Deploying lithium battery recycling would cause severe environmental hazards, would pose risks to human health, and would also be a waste of resources. In this paper, a combined process of diffusion dialysis (DD) and electrodialysis (ED) is proposed to separate, recover, and utilize Ni2+ and H2SO4 in the wastewater. In the DD process, the acid recovery rate and Ni2+ rejection rate could reach 75.96% and 97.31%, respectively, with a flow rate of 300 L/h and a W/A flow rate ratio of 1:1. In the ED process, the recovered acid from DD is concentrated from 43.1 g/L to 150.2 g/L H2SO4 by the two-stage ED, which could be used in the front-end procedure of battery recycling process. In conclusion, a promising method for the treatment of battery wastewater which achieved the recycling and utilization of Ni2+ and H2SO4 was proposed and proved to have industrial application prospects.

Recovery of residual metals from jarosite waste using chemical and biochemical processes to achieve sustainability: A state-of-the-art review

Jarosite is a residue that is generated as a by-product during zinc extraction, and it consists of various types of heavy metal (loid)s such as arsenic, cadmium, chromium, iron, lead, mercury and silver. Due to the huge jarosite turn-over rate, and less efficient and expensive residual metal extraction processes, the zinc-producing industries dispose this waste in landfills. However, the leachate generated from such landfills contains a high concentration of heavy metal (loid)s that could contaminate the nearby water resources and cause environmental concern and human health risk. Various thermo-chemical and biological processes have been developed for the recovery of heavy metals from such waste. In this review, we have discussed all those pyrometallurgical, hydrometallurgical, and biological. Those studies were critically reviewed and compared on the basis of their techno-economic differences. The review indicated that these processes have their own benefits and drawbacks such as overall yield, economic and technical constraints, and the need for more than one process to mobilize multiple metal ions from jarosite. Also, in this review, the residual metal extraction processes from jarosite waste have been linked with the relevant UN Sustainable Development Goals (SDGs), which can be useful for a better approach to sustainable development.

Heavy metals and metalloids accumulation in common beans (Phaseolus vulgaris L.): A review

Heavy metals (HMs) and metalloids (Ms) such as arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb) represent serious environmental threats due to their wide abundance and high toxicity. Contamination of water and soils by HMs and Ms from natural or anthropogenic sources is of great concern in agricultural production due to their toxic effects on plants, adversely affecting food safety and plant growth. The uptake of HMs and Ms by Phaseolus vulgaris L. plants depends on several factors including soil properties such as pH, phosphate, and organic matter. High concentrations of HMs and Ms could be toxic to plants due to the increased generation of reactive oxygen species (ROS) such as (O2•-), (•OH), (H2O2), and (1O2), and oxidative stress due to an imbalance between ROS generation and antioxidant enzyme activity. To minimize the effects of ROS, plants have developed a complex defense mechanism based on the activity of antioxidant enzymes such as SOD, CAT, GPX, and phytohormones, especially salicylic acid (SA) that can reduce the toxicity of HMs and Ms. This review focuses on evaluating the accumulation and translocation of As, Cd, Hg, and Pb in Phaseolus vulgaris L. plants and on their possible effects on the growth of Phaseolus vulgaris L. in soil contaminated with these elements. The factors that affect the uptake of HMs and Ms by bean plants, and the defense mechanisms under oxidative stress caused by the presence of As, Cd, Hg, and Pb are also discussed. Furthermore, future research on mitigating HMs and Ms toxicity in Phaseolus vulgaris L. plants is highlighted