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Review

Heavy Metal Contamination in the Aquatic Ecosystem: Toxicity and Its Remediation Using Eco-Friendly Approaches

by
Veer Singh
1,2,†,
Nidhi Singh
3,†,
Sachchida Nand Rai
4,†,
Ashish Kumar
1,†,
Anurag Kumar Singh
5,
Mohan P. Singh
4,
Ansuman Sahoo
6,
Shashank Shekhar
7,
Emanuel Vamanu
8,* and
Vishal Mishra
2,*
1
Department of Biochemistry, Rajendra Memorial Research Institute of Medical Sciences, Patna 800007, India
2
School of Biochemical Engineering, Indian Institute of Technology, Banaras Hindu University, Varanasi 221005, India
3
Centre of Bioinformatics, University of Allahabad, Prayagraj 211002, India
4
Centre of Biotechnology, University of Allahabad, Prayagraj 211002, India
5
Centre of Experimental Medicine & Surgery, Institute of Medical Sciences, Banaras Hindu University, Varanasi 221005, India
6
Department of Botany, Banaras Hindu University, Varanasi 221005, India
7
Udai Pratap Autonomous College, Varanasi 221002, India
8
Faculty of Biotechnology, University of Agricultural Sciences and Veterinary Medicine of Bucharest, Bucharest 011464, Romania
*
Authors to whom correspondence should be addressed.
†
These authors contributed equally to this work.
Toxics 2023, 11(2), 147; https://doi.org/10.3390/toxics11020147
Submission received: 19 December 2022 / Revised: 24 January 2023 / Accepted: 1 February 2023 / Published: 3 February 2023
(This article belongs to the Special Issue Toxicity of Metal Mixtures to Aquatic Life)
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Abstract

:
Urbanization and industrialization are responsible for environmental contamination in the air, water, and soil. These activities also generate large amounts of heavy metal ions in the environment, and these contaminants cause various types of health issues in humans and other animals. Hexavalent chromium, lead, and cadmium are toxic heavy metal ions that come into the environment through several industrial processes, such as tanning, electroplating, coal mining, agricultural activities, the steel industry, and chrome plating. Several physical and chemical methods are generally used for the heavy metal decontamination of wastewater. These methods have some disadvantages, including the generation of secondary toxic sludge and high operational costs. Hence, there is a need to develop a cost-effective and eco-friendly method for the removal of heavy metal ions from polluted areas. Biological methods are generally considered eco-friendly and cost-effective. This review focuses on heavy metal contamination, its toxicity, and eco-friendly approaches for the removal of heavy metals from contaminated sites.

1. Introduction

Environmental contaminants are substances that are present in the natural environment at levels higher than their permissible limits [1]. Industrialization and urbanization have emerged as the major causes of environmental pollution over the last few decades. The utilization of natural resources at a careless rate creates disturbances in the environment and causes several related problems [2]. There are several types of pollutants, such as organic, inorganic, metallic, gaseous and biological pollutants, which contaminate the environment [3]. Contamination from metallic ions in water arises due to several natural and anthropogenic activities, which harm animals and plants [4].
Heavy metals are characterized by their higher atomic weight or higher density. The term ‘heavy metal’ is used to describe metalloids or metallic elements which have toxic effects on humans and other living organisms [5]. Heavy metals including arsenic (As), chromium (Cr), lead (Pb), and cadmium (Cd) are toxic to humans, but a few heavy metals are not toxic; these include gold (Au) [6]. The density of heavy metals is commonly greater than 5 g/cm3: for example, Cr, Cd, and Pb [7]. The human body is generally exposed to heavy metal ions in one of four ways: the ingestion of metal-contaminated food, drinking contaminated water, skin contact, and inhalation in metal-contaminated air [8]. Metal compounds tend to form covalent bonds, which are responsible for the extremely toxic nature of metalloid compounds. Heavy metals can become covalently attached to organic groups and form lipophilic compounds or ions [9]. Due to the lipophilic nature of these metallic compounds, they pass through the cell membrane and enter the cell. These metallic compounds cause toxic effects when they interact with cell organelles [10].
Various technologies are available for the minimization of toxic metal ions from water. Physiochemical methods, such as filtration, ion exchange, reverse osmosis, precipitation, and physical adsorption, are frequently used for heavy metal treatment [11]. Precipitation is a well-known technique for the removal of Cr (VI), as well as Pb (II) and Cd (II). The precipitation is undertaken by varying the pH of wastewater [12,13]. These physiochemical techniques are expensive and generate secondary chemical sludge; moreover, these methods are only effective when the concentration of heavy metals is higher in the water (above 2 mM) [14]. Considering the disadvantages of these physiochemical methods, there is an urgent need to develop cost-effective and eco-friendly methods for the successful removal of heavy metals from water [15].
Bioremediation methods, such as biosorption, bio-reduction, bioaccumulation, mycoremediation, bacterial bioremediation, and phytoremediation, are considered inexpensive and eco-friendly methods [16]. Biosorption is an eco-friendly and inexpensive method which is used for the extraction of metal ions from contaminated water [17]. A variety of biomaterials, including rice and wheat husks, activated carbon, lignite, agro-waste, banana and citrus limetta peels, and green synthesized nanoparticles, are active biosorbents that can be used for the extraction of toxic metallic pollutants [18]. Living microbes, such as bacteria and fungi, are also effective remediating agents. This is due to the high metal-tolerance properties of fungi (Pleurotus florida) and bacteria. Several functional groups on the bacterial surface participate in the binding of heavy metals to the bacterial surface [19]. Heavy metals enter the cell and either bind to the cell membrane or are reduced into a less toxic form. The antioxidant systems of microbial cells reduce toxicity and aid bioaccumulation [20].
This review focuses on the sources of heavy metal contamination in water and its toxic effect on human beings and other living organisms. In this study, we also outline advanced, effective methods for the removal of heavy metals.

2. The Source and Toxicity of Heavy Metal Ions

Several industrial processes, including leather tanning, chrome plating, battery manufacturing, the glass industries, agricultural activities, domestic waste, and pharmaceutical industrial processes, are considered major sources of heavy metals, which generate toxic metal ions in the environment [21,22]. According to the International Leadership Association, about ten million tons of Pb (II) have been generated; 85.10% of the total amount of Pb (II) produced has been used in the battery industry, 5.5% in pigments, and the rest in the miscellaneous category (2.1%) (ILA, 2017). Pb (II) is also used in petrol as tetraethyl and tetramethyl agents in the form of antiknocking compounds [23]. Cr (VI) is used for steel production, wood preservation, chrome plating, pigments, and electroplating [24,25]. Cd is generally used in the electroplating and battery industries [26]. The Central Pollution Control Board (CPCB) has demarcated the maximum discharge limit of heavy metals in industrial effluent (Table 1).
The USA’s environmental protection agency (USEPA) has demarcated the maximum permissible limit of heavy metals in drinking water. The allowable concentrations of heavy metals in drinking water are listed in Table 2.
Beyond these permissible limits, heavy metals cause several toxic effects. Some heavy metals are considered potential carcinogens [30,31]. The toxicity of heavy metal ions is shown in Figure 1.
Cr (VI) is a highly dangerous metallic ionic species, and its toxicity depends on its oxidation state [32,33]. It is a powerful oxidizing agent and shows much higher levels of toxicity than Cr (III). Cr (VI) enters the cell through the cell membrane and transforms into Cr (III) [34]. Cr (VI) reduces into Cr (III) and generates reactive oxygen species (ROS), which can damage internal components of the cell [35]. The Cr (VI) transformation process is known as a detoxification mechanism, which takes place away from the nucleus and other cell components. The reduction process also sometimes occurs outside of the cell through extracellular secretion [36]. Cr (VI)-reduction-mediated ROS generation can cause mutations in the DNA and damage cell organelles [37]. If the reduction of Cr (VI) occurs outside of the cell, Cr (III) is reduced and other intermediate reactions cannot deliver it into the cell, and toxicity is not observed [38]. Several researchers have noted that Cr (VI) is responsible for cancer and the damage of multiple organs, such as the liver and kidneys [39]. Gumbleton and Nicholls [40] indicated that Cr (VI) toxicity is responsible for kidney failure in rats. It has been reported that Cr (VI) is also responsible for respiratory cancer, the breakage of DNA strands, and abnormalities in chromosomes [41].
The main cause of Cd (II) exposure in humans is inhalation, through the ingestion of food and drinking of Cd (II)-contaminated water [42]. The chronic inhalation of Cd (II) causes a change in pulmonary functions, a reduction in olfactory functions, and emphysema [43]. Ingested Cd (II) causes abdominal pain, loss of consciousness, vomiting, nausea, hepatic injury, renal failure, gastrointestinal erosion, and a burning sensation [44]. It is also responsible for pulmonary adenocarcinomas and damage to single DNA strands, and disrupts the synthesis of proteins and nucleic acids [45].
Both natural and anthropogenic activities, such as mining, the burning of fossil fuels, and the manufacturing of batteries and glasses, are major sources of Pb (II) (https://fas.org/sgp/crs/misc/R46420.pdf (accessed on 16 June 2020). The toxic effects of Pb (II) in children come from dust and the chips used in packed food products, as it is used as a coating on the interior surfaces of packing materials [46]. The organs in the body that are most affected by Pb (II) toxicity are the kidneys, liver, and other soft tissues, such as the brain and heart [47]. Pb (II) toxicity massively impacts the nervous system. Poor attention, headaches, dullness, irritability, and memory loss are the early symptoms of Pb (II) poisoning in the central nervous system [48,49].

3. Removal of Heavy Metal Ions

The biological removal of heavy metals is more appealing than other conventional methods, because biological methods are cost-effective, eco-friendly, and efficient when removing low concentrations of heavy metal ions from wastewater [12]. Several biological agents, such as plant biomass, agricultural waste, microbial biomass, green synthesized nanoparticles, fruit waste, and biopolymers, have been utilized for the removal of heavy metals [50,51]. Living organisms, such as bacteria, algae, and fungi, also increasingly play a role in the removal of heavy metals [52]. Several microbes, such as fungi, bacteria, and algae, take heavy metals into their cells from the surrounding medium [53]. It has been reported that various microbial species can transform highly toxic Cr (VI) into less toxic Cr (III). Microorganisms can easily take Cr (III) into their cells as it has lower solubility in water and low toxicological properties [54]. Several heavy metal bioremediation methods, including biosorption (using dead biomass), phytoremediation (plant-mediated heavy metal removal), bioreduction (the conversion of oxidation states of heavy metal ions), and bioaccumulation (the uptake of heavy metal ions into intracellular space) have been proposed in past [55]. Heavy metals can be remediated using metabolically independent (dead materials) and metabolically dependent (live cells of bacteria, fungi, and algae) agents.

3.1. Metabolically Independent Approaches for Heavy Metal Removal

The phenomenon of biosorption is considered to be metabolically independent, and the biosorption process is generally performed by dead biomass, such as plant biomass, agro-waste, microbial biomass, and green synthesized nanomaterials. In biosorption, heavy metal ions bind to the surface of the adsorbent through several functional groups that are present on the surface [18,56]. However, it is also performed by live cell biomass; living microbial cells can bind heavy metal ions on their cell surface by passive adsorption and complexation [57,58].
Biosorption can be described as the binding of heavy metal ions to surface functional groups, including amino, amide, imidazole, sulfonate, and carboxyl groups [59]. The pKa value of the medium also plays important role in the adsorption of heavy metal ions and the binding tendencies of functional groups [60]. One of the most important and memorable aspects of biosorption is the selection of a suitable biosorbent. The raw material used for adsorption should be easily available, non-toxic, and cost-effective [61]. The dispersity of surface groups also determines the biosorbent‘s quality. For an ideal biosorbent, the density of the surface functional groups should be high [62]. The surface morphology is an important characteristic of adsorbents, and plays an important role in heavy metal adsorption. Rough and porous surfaces provide a larger surface area, and are advantageous for binding heavy metal ions on the biosorbent’s surface [63]. It is important to characterize the surface morphology and functional groups of biosorbents. Various techniques, such as Fourier transformation infra-red (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), nuclear magnetic resonance (NMR), and X-ray diffraction (XRD), are used for the characterization of biosorbents [64,65].
Biosorption is affected by several factors including the morphology and types of biomass, the presence of more than one metal ion in the media, and the surrounding temperature and pH of the medium [66]. Commonly, a decrease in the pH is responsible for competition between cationic heavy metal ions. However, elevation in pH is responsible for the deprotonation of the adsorbent surface and causes the exposure of surface functional groups [66,67]. The regeneration of the biosorbent can be also achieved by using desorption. The recovery of metal ions was achieved by varying the pH of the medium [17,68]. In addition, the Cr (VI) biosorption mechanism is a complex phenomenon in which a Cr (VI) ion is attached to the biosorbent’s surface and reduced into less toxic Cr (III) [69].
The reduction-cum-adsorption of Cr (VI) usually occurs in three stages: (1) the binding of negatively charged chromate ions to the positive functional groups; (2) the reduction of Cr (VI) into Cr (III) through an electron donated by the functional groups; (3) the release of Cr (III) ions into the solution, with the remaining Cr (III) ions staying bound to the adsorbent surface with negatively charged surface functional groups [70,71,72].
The biosorption phenomenon can be also performed on immobilized biomass, such as bacterial biomass on a solid surface, fungal biomass on a supportive medium, or dead biomass immobilized on another supportive surface. Immobilization improves the rigidity, strength, and age of the biosorbent and improves its biosorption capacity [73]. Various types of matrices are available and are used for immobilization; these include alginate and polyurethane [74,75]. Additionally, several microbial and plant biomasses have been utilized for immobilization on the above-described matrices: for example, the biomass of Chlorella homosphaera immobilized on a sodium alginate matrix [76]. Table 3, Table 4 and Table 5 show the uptake capacity of various biosorbents in terms of Cr (VI), Cd (II), and Pb (II), respectively.
The above-mentioned biomasses are considered effective biosorbents for the removal of heavy metal ions. In addition, nanoparticles are receiving increased attention in the field of heavy metal removal. Nanoparticles also have applications in electron devices, health care, energy, agriculture, and wastewater treatment [94,95]. In general, nanoparticles are small in size within the nanoscale (1–100 nm), and the small size of nanomaterials provides a large surface area as compared to bulk materials [96]. Along with their small particle size, nanoparticles have some other important properties, such as quantum and macro-quantum tunnel effects [94,96]. These specific properties of nanoparticles are responsible for their unusual reactivity and adsorption properties. These properties of nanomaterials are favorable for the biosorption of heavy metals from contaminated media [94,97]. Several types of nanoparticles have been synthesized for the removal of heavy metal ions, and a few examples of these nanomaterials and their heavy metal adsorption capacities are shown in Table 6.

3.2. Metabolically Dependent Approaches for Heavy Metal Removal

Bioaccumulation is a phenomenon in which heavy metal ions accumulate inside the microbial cells [106,107]. It is a highly complex phenomenon and slower than biosorption, because several metabolic pathways actively participate in this process [106]. The bioaccumulation process is performed by living microbial cells in the suspension medium and requires continuous observation [108]. It minimizes several steps of biosorbent preparation, such as the harvesting of biomass, the drying of biomass, and the preparation (washing and crushing) and storage of biomass [109]. However, bioaccumulation is hypersensitive to experimental conditions [110]. Pollutants present in wastewater affect microbial growth and also cause competition with the heavy metal ions selected for bioaccumulation. Moreover, these pollutants can bind to the bacterial outer surface and disrupt heavy metal accumulation in cells [111]. Several fungi, bacteria, algae, and plant species have been shown to play an important role in the removal of heavy metals.
Among these living systems, microbes have a good ability to remove heavy metals, and also possess resistant properties. Bacteria can uptake heavy metal ions through cell surface receptors and accumulate heavy metal ions inside the bacteria [112]. Several bacterial cell, such as those of the Pseudomonas species [113], the Klebsiella species [114], and the Microbacterium species [115], are resistant to the heavy metal ions isolated from several contaminated sites [116]. Bacteria isolated from heavy-metal-contaminated sites generally became resistant to heavy metal ions [117]. Several researchers have identified heavy-metal-resistant Microbacterium strains from contaminated areas. Henson et al. [118] isolated a Microbacterium sp. (Cr-K29) that was capable of removing 88% of Cr (VI) from contaminated water. According to Pattanapipitpaisal et al. [119] Microbacterium liquefaciens is capable of removing 81% of Cr (VI) from wastewater in an immobilized microbial form on a solid surface. Bacteria utilize various mechanisms for the removal of heavy metals. Bacteria can utilized heavy metal ions for their metabolic activity, or else they detoxify heavy metal ions through soluble enzymes produced by the bacterial cells [120]. The overall bioremediation of Cr (VI) by bacteria is shown in Figure 2.
ROS are generated in bacterial cells when these cells are exposed to toxic heavy metals. ROS damage the cell organelles and affect several metabolic functions which control normal cell functions [121,122]. Thus, antioxidant systems, such as superoxide dismutase (SOD) and catalase in the microbial cells, are actively involved in the detoxification of ROS-generated stress in bacterial cells [123]. Several heavy-metal-resistant bacterial species have been identified by researchers. The Cr (VI), Pb (II), and Cd (II) bioremediation efficiency of heavy-metal-tolerant bacterial strains is shown in Table 7, Table 8 and Table 9, respectively.

3.3. Other Bio-Remedial Techniques

Other bio-remedial techniques, such as phytoremediation, capacitive deionization, electrosorption, the metagenomic approach, and diatom-mediated heavy metal bioremediation, can effectively be used in wastewater treatment.
Phytoremediation is a plant-based technique used for the removal of heavy metal ions and other contaminants from water and soil. Plants can tolerate heavy metal stress and can grow in areas highly contaminated with heavy metals. Hence, plants can remove heavy metals from water and soil by taking up heavy metals through their roots. There are some disadvantages to phytoremediation; some plants require large areas to grow and have long growth times, and it is difficult to maintain the growth of some plants in water [134].
The capacitive deionization (CDI) process has gained attention as a possible method for heavy metal removal in recent years. The cost-effective and widely available materials have facilitated the growth of electrosorption research. Hence, CDI is based on inexpensive and eco-friendly methods for the removal of heavy metals from wastewater. CDI has recently shifted towards electrosorption for the removal of selective heavy metal ions from water, and it is suitable for industrial wastewater treatment [135].
Metagenomics is a technique used for the identification of microbial communities in environmental samples. Several cultured and uncultured microbes are present in the soil, water, and air. Some of these microbes can grow in high-stress conditions, such as heavy metal stress. These microbes are resistant to heavy metal ions and can take up heavy metals into their intracellular space, or convert them into less toxic forms [136].
Heavy metal ions are present in both freshwater and marine ecosystems. Diatoms play an important role in the removal, degradation, and detoxification of heavy metal ions from contaminated sites [137]. Diatom algae are diverse and have extensive evolutionary variations in their metabolic pathways. Diatoms show higher productivity and can easily grow in an aqueous medium. Diatoms utilize abiotic and biotic mechanisms to contaminate and easily adapt to varying environmental conditions. Diatom-based strategies are considered a cost-effective and sustainable method for the removal of heavy metal ions from contaminated water [138].

3.4. Disadvantages and Advantages of Methods of Heavy Metal Removal

Metabolically dependent heavy metal removal is required for growth-specific media used for microbial growth. Moreover, other growth parameters, such as pH, temperature, and agitation, are necessary for the proper growth of microbes [97]. Hence, bioremediation methods based on living microorganisms require more energy input and other media components. Heavy metal removal methods based on non-living organisms are metabolically independent and do not require media or a great deal of energy input, such as that required by living organisms. Moreover, biological methods are yet to be established and commercialized. Beyond these disadvantages, these biological methods are cost-effective, eco-friendly, and effective at very low concentrations of heavy metal ions in water [97,139].

3.5. Challenges of Heavy Metal Remediation Technologies and Future Prospects

Heavy metal remediation technologies are time-consuming and laborious. In addition, the major challenges for bioremediation techniques concern their implementation at the commercial level and their application in water treatment plants [140]. These techniques involve the use of chelating agents and surfactants for the modification of the adsorbent surface, and bacterial immobilization on the solid surface and the use of composite nanomaterial or biopolymers to increase the removal of heavy metals from water. However, future research can explore the potential of using biological remediation methods for the removal of other toxic metal ions such as As, Ni, Hg, and Cu. Advanced technical duty/assessment tools, such as lifecycle assessments and the exergo-environmental and exergo-economic investigation of large-scale wastewater treatment plants, can also be used in future to develop cost-effective, energy-saving, and eco-friendly systems. Additionally, the molecular mechanisms of heavy metal removal and comparative transcriptomic analysis may be considered in future research [12,34].

4. Conclusions

Heavy metal ions are used in many industrial processes, such as tanning and chrome plating. Heavy metal ions including Cd (II), Pb (II), As (III and V), and Cr (VI) are the substances that pose the most danger to human health. Some of these metal ions are also released into the environment and cause contamination. The presence of heavy metal ions in the water and soil affects human health, as well as the health of some aquatic and terrestrial animals. Several types of cancer, kidney and liver damage, skin problems, and mental dullness are well-known health issues caused by heavy metal toxicity. Membrane filtration, reverse osmosis, chemical reduction, and adsorption are the major conventional methods used for the removal of heavy metal ions from wastewater [141]. However, these methods generate large amounts of secondary pollutants and are costly compared to biological methods. These eco-friendly methods have many more advantages than conventional methods. In this review, we summarized the biological methods, including both metabolically dependent and metabolically independent methods, for heavy metal removal. Moreover, this review also focused on the sources of heavy metals and their toxicity. This study improves our understanding of how to design effective biological wastewater treatment systems.

Author Contributions

V.S., N.S., A.K. and S.N.R., writing—original draft preparation, including figures and tables; conceptualization, A.K.S., M.P.S., A.S. and S.S.; writing—reviewing and editing, V.M. and E.V.; supervision, writing—reviewing and editing. All authors have read and agreed to the published version of the manuscript.

Funding

This research received no external funding.

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

Not applicable.

Acknowledgments

The authors thank the Indian Institute of Technology (BHU), the University of Allahabad, Banaras Hindu University, and the Rajendra Memorial Research Institute of Medical Sciences for providing the necessary support for this work.

Conflicts of Interest

The authors declare that they have no conflict of interest.

References

  1. Rahman, Z.; Singh, V.P. The relative impact of toxic heavy metals (THMs) (arsenic (As), cadmium (Cd), chromium (Cr)(VI), mercury (Hg), and lead (Pb)) on the total environment: An overview. Environ. Monit. Assess. 2019, 191, 419. [Google Scholar] [CrossRef] [PubMed]
  2. Jarup, L. Hazards of heavy metal contamination. Br. Med. Bull. 2003, 68, 167–182. [Google Scholar] [CrossRef] [PubMed]
  3. Martin, Y.E.; Johnson, E.A. Biogeosciences survey: Studying interactions of the biosphere with the lithosphere, hydrosphere and atmosphere. Prog. Phys. Geogr. 2012, 36, 833–852. [Google Scholar] [CrossRef]
  4. Kinuthia, G.K.; Ngure, V.; Beti, D.; Lugalia, R.; Wangila, A.; Kamau, L. Levels of heavy metals in wastewater and soil samples from open drainage channels in Nairobi, Kenya: Community health implication. Sci. Rep. 2020, 10, 8434. [Google Scholar] [CrossRef]
  5. Singh, R.; Gautam, N.; Mishra, A.; Gupta, R. Heavy metals and living systems: An overview. Indian J. Pharmacol. 2011, 43, 246–253. [Google Scholar] [CrossRef]
  6. Tchounwou, P.B.; Yedjou, C.G.; Patlolla, A.K.; Sutton, D.J. Heavy Metals Toxicity and the Environment. EXS 2012, 101, 133–164. [Google Scholar]
  7. Wu, X.; Cobbina, S.J.; Mao, G.; Xu, H.; Zhang, Z.; Yang, L. A review of toxicity and mechanisms of individual and mixtures of heavy metals in the environment. Environ. Sci. Pollut. Res. Int. 2016, 23, 8244–8259. [Google Scholar] [CrossRef]
  8. Jaishankar, M.; Tseten, T.; Anbalagan, N.; Mathew, B.B.; Beeregowda, K.N. Toxicity, mechanism and health effects of some heavy metals. Interdiscip. Toxicol. 2014, 7, 60–72. [Google Scholar] [CrossRef]
  9. Jan, A.T.; Azam, M.; Siddiqui, K.; Ali, A.; Choi, I.; Mohd, Q.; Haq, R. Heavy Metals and Human Health: Mechanistic Insight into Toxicity and Counter Defense System of Antioxidants. Int. J. Mol. Sci. 2015, 16, 29592–29630. [Google Scholar] [CrossRef]
  10. Briffa, J.; Sinagra, E.; Blundell, R. Heavy metal pollution in the environment and their toxicological effects on humans. Heliyon 2020, 6, e04691. [Google Scholar] [CrossRef]
  11. Khulbe, K.C.; Matsuura, T. Removal of heavy metals and pollutants by membrane adsorption techniques. Appl. Water Sci. 2018, 8, 19. [Google Scholar] [CrossRef] [Green Version]
  12. Qasem, N.A.A.; Mohammed, R.H.; Lawal, D.U. Removal of heavy metal ions from wastewater: A comprehensive and critical review. NPJ Clean Water 2021, 4, 36. [Google Scholar] [CrossRef]
  13. Kurniawan, T.A.; Chan, G.Y.S. Physico–chemical treatment techniques for wastewater. Chem. Eng. J. 2006, 118, 83–98. [Google Scholar] [CrossRef]
  14. Anirudhan, T.S.; Sreekumari, S.S. Adsorptive removal of heavy metal ions from industrial effluents usingactivated carbon derived from waste coconut buttons. J. Environ. Sci. 2011, 23, 1989–1998. [Google Scholar] [CrossRef] [PubMed]
  15. Wołowiec, M.; Komorowska-Kaufman, M.; Pruss, A.; Rzepa, G.; Bajda, T. Removal of Heavy Metals and Metalloids from Water Using Drinking Water Treatment Residuals as Adsorbents: A Review. Minerals 2019, 9, 487. [Google Scholar] [CrossRef]
  16. Singh, V.; Singh, J.; Singh, N.; Rai, S.N.; Verma, M.K.; Verma, M.; Singh, V.; Chivate, M.S.; Bilal, M.; Mishra, V. Simultaneous removal of ternary heavy metal ions by a newly isolated Microbacterium paraoxydans strain VSVM IIT(BHU) from coal washery effluent. BioMetals 2022, 2022, 1–17. [Google Scholar] [CrossRef]
  17. Jobby, R.; Jha, P.; Yadav, A.K.; Desai, N. Biosorption and biotransformation of hexavalent chromium [Cr(VI)]: A comprehensive review. Chemosphere 2018, 207, 255–266. [Google Scholar] [CrossRef]
  18. Gadd, G.M. Biosorption: Critical review of scientific rationale, environmental importance and significance for pollution treatment. J. Chem. Technol. Biotechnol. 2007, 84, 13–28. [Google Scholar] [CrossRef]
  19. Singh, V.; Singh, N.; Verma, M.; Kamal, R.; Tiwari, R.; Chivate, M.S.; Rai, S.N.; Kumar, A.; Singh, A.; Singh, M.P.; et al. Hexavalent-Chromium-Induced Oxidative Stress and the Protective Role of Antioxidants against Cellular Toxicity. Antioxidants 2022, 12, 2375. [Google Scholar] [CrossRef]
  20. Zafar, S.; Aqil, F.; Ahmad, I. Metal tolerance and biosorption potential of filamentous fungi isolated from metal contaminated agricultural soil. Bioresour. Technol. 2007, 98, 2557–2561. [Google Scholar] [CrossRef]
  21. Singh, V.; Mishra, V. Microbial Removal of Cr (VI) by a New Bacterial Strain Isolated from the Site Contaminated with Coal Mine Effluents. J. Environ. Chem. Eng. 2021, 9, 106279. [Google Scholar] [CrossRef]
  22. Wuana, R.A.; Okieimen, F.E. Heavy Metals in Contaminated Soils: A Review of Sources, Chemistry, Risks and Best Available Strategies for Remediation. Int. Sch. Reseach Not. 2011, 2011, 402647. [Google Scholar] [CrossRef]
  23. Quinn, M.J.; Sherlock, J.C. The correspondence between U.K. ‘action levels’ for lead in blood and in water. Food Addit. Contam. 1990, 7, 387–424. [Google Scholar] [CrossRef]
  24. Singh, V.; Singh, J.; Mishra, V. Sorption kinetics of an eco-friendly and sustainable Cr (VI) ion scavenger in a batch reactor. J. Environ. Chem. Eng. 2021, 9, 105125. [Google Scholar] [CrossRef]
  25. Lunk, H.J. Discovery, properties and applications of chromium and its compounds. ChemTexts 2015, 1, 6. [Google Scholar] [CrossRef]
  26. Panakkal, A.; Kumar, R.B.B. Evaluation of the trace metal contamination in sediments of the urban water channels in Thrissur City, South India. Nat. Environ. Pollut. Technol. 2014, 13, 701–706. [Google Scholar]
  27. Central Pollution Control Board (CPCB), India (2000) Environmental Standards for Ambient Air, Automobiles, Fuels, Industries and Noise. Available online: http://www.cpcbenvis.nic.in/scanned%20reports/PCL%204%20Environmental%20Standards.pdf (accessed on 1 July 2000).
  28. EPA 822-F-18-001; 2018 Edition of the Drinking Water Standards and Health Advisories. United States Environmental Protection Agency (USEPA): Washington, DC, USA, 2018.
  29. World Health Organization (WHO). Guidelines for Drinking Water Quality; WHO: Geneva, Switzerland, 2011. [Google Scholar]
  30. Yuan, W.; Yang, N.; Li, X. Advances in Understanding How Heavy Metal Pollution Triggers Gastric Cancer. BioMed Res. Int. 2016, 2016, 7825432. [Google Scholar] [CrossRef] [PubMed]
  31. Balali-Mood, M.; Naseri, K.; Tahergorabi, Z.; Khazdair, M.R.; Sadeghi, M. Toxic Mechanisms of Five Heavy Metals: Mercury, Lead, Chromium, Cadmium, and Arsenic. Front. Pharmacol. 2021, 12, 643972. [Google Scholar] [CrossRef]
  32. Singh, V.; Singh, J.; Mishra, V. Development of a cost-effective, recyclable and viable metal ion doped adsorbent for simultaneous adsorption and reduction of toxic Cr (VI) ions. J. Environ. Chem. Eng. 2021, 9, 105124. [Google Scholar] [CrossRef]
  33. Bokare, A.D.; Choi, W. Advanced oxidation process based on the Cr(III)/Cr(VI) redox cycle. Environ. Sci. Technol. 2011, 45, 9332–9338. [Google Scholar] [CrossRef]
  34. Singh, V.; Mishra, V. Sustainable reduction of Cr (VI) and its elemental mapping on chitosan coated citrus limetta peels biomass in synthetic wastewater. Sep. Sci. Technol. 2021, 57, 1609–1626. [Google Scholar] [CrossRef]
  35. Singh, V.; Singh, M.P.; Mishra, V. Bioremediation of toxic metal ions from coal washery effluent. Desalination Water Treat. 2020, 197, 300–318. [Google Scholar] [CrossRef]
  36. Singh, V.; Singh, N.; Yadav, P.; Mishra, V. Removal of Hexavalent Chromium from Aqueous Media Using Eco-Friendly and Cost-Effective Biological Methods. In Biosorption for Wastewater Contaminants; Selvasembian, R., Singh, P., Eds.; John Wiley & Sons: Hoboken, NJ, USA, 2021; pp. 246–268. [Google Scholar] [CrossRef]
  37. Wakeel, A.; Xu, M.; Gan, Y. Chromium-Induced Reactive Oxygen Species Accumulation by Altering the Enzymatic Antioxidant System and Associated Cytotoxic, Genotoxic, Ultrastructural, and Photosynthetic Changes in Plants. Int. J. Mol. Sci. 2020, 21, 728. [Google Scholar] [CrossRef]
  38. Cohen, M.D.; Kargacin, B.; Klein, C.B.; Costa, M. Mechanisms of chromium carcinogenicity and toxicity. Crit. Rev. Toxicol. 1993, 23, 255–281. [Google Scholar] [CrossRef]
  39. Kim, E.; Na, K.J. Nephrotoxicity of sodium dichromate depending on the route of administration. Arch. Toxicol. 1991, 65, 537–541. [Google Scholar] [CrossRef] [PubMed]
  40. Gumbleton, M.; Nicholls, P.J. Dose-response and time-response biochemical and histological study of potassium dichromate-induced nephrotoxicity in the rat. Food Chem. Toxicol. 1988, 26, 37–44. [Google Scholar] [CrossRef] [PubMed]
  41. Wise, S.S.; Holmes, A.L.; Ketterer, M.E.; Hartsock, W.J.; Fomchenko, E.; Katsifis, S.P.; Thompson, W.D.; Wise, J.P. Chromium is the proximate clastogenic species for lead chromate-induced clastogenicity in human bronchial cells. Mutat. Res. 2004, 560, 79–89. [Google Scholar] [CrossRef] [PubMed]
  42. Genchi, G.; Sinicropi, M.S.; Lauria, G.; Carocci, A.; Catalano, A. The Effects of Cadmium Toxicity. Int. J. Environ. Res. Public Health 2020, 17, 3782. [Google Scholar] [CrossRef]
  43. Rahimzadeh, M.R.; Rahimzadeh, M.R.; Kazemi, S.; Moghadamnia, A.K. Cadmium toxicity and treatment: An update. Caspian J. Intern. Med. 2017, 8, 135–145. [Google Scholar]
  44. Baselt, R.C.; Cravey, R.H. Disposition of Toxic Drugs and Chemicals in Man, 4th ed.; Year Book Medical Publishers: Chicago, IL, USA, 1995; pp. 105–107. [Google Scholar]
  45. Waalkes, M.P.; Berthan, G. (Eds.) Handbook on Metal-Ligand Interactions of Biological Fluids; Marcel Dekker: New York, NY, USA, 1995; Volume 2, pp. 471–482. [Google Scholar]
  46. Lanphear, B.P.; Matte, T.D.; Rogers, J.; Clickner, R.P.; Dietz, B.; Bornschein, R.L.; Succop, P.; Mahaffey, K.R.; Dixon, S.; Galke, W.; et al. The contribution of lead-contaminated house dust and residential soil to children’s blood lead levels. A pooled analysis of 12 epidemiologic studies. Environ. Res. 1998, 79, 51–68. [Google Scholar] [CrossRef]
  47. Flora, S.J.S.; Flora, G.J.S.; Saxena, G. Environmental occurrence, health effects and management of lead poisoning. In Lead: Chemistry, Analytical Aspects, Environmental Impacts and Health Effects; Cascas, S.B., Sordo, J., Eds.; Elsevier Publication: Amsterdam, The Netherlands, 2006; pp. 158–228. [Google Scholar]
  48. Centers for Disease Control and Prevention (CDC). Managing Elevated Blood Lead Levels Among Young Children: Recommendations from the Advisory Committee on Childhood Lead Poisoning Prevention. 2001. Available online: https://www.cdc.gov/nceh/lead/casemanagement/managingEBLLs.pdf (accessed on 31 March 2002).
  49. ATSDR. Public Health Service. Toxicological Profile for Lead. 2020. Available online: https://www.atsdr.cdc.gov/toxprofiles/tp13.pdf (accessed on 31 August 2020).
  50. Kumar, H.; Bhardwaj, K.; Sharma, R.; Nepovimova, E.; Kuča, K.; Dhanjal, D.S.; Verma, R.; Bhardwaj, P.; Sharma, S.; Kumar, D. Fruit and Vegetable Peels: Utilization of High Value Horticultural Waste in Novel Industrial Applications. Molecules 2020, 25, 2812. [Google Scholar] [CrossRef] [PubMed]
  51. Abdelbasir, S.M.; McCourt, K.M.; Lee, C.M.; Vanegas, D.C. Waste-Derived Nanoparticles: Synthesis Approaches, Environmental Applications, and Sustainability Considerations. Front. Chem. 2020, 8, 782. [Google Scholar] [CrossRef] [PubMed]
  52. Tarekegn, M.M.; Salilih, F.Z.; Ishetu, A.I.; Yildiz, F. Microbes used as a tool for bioremediation of heavy metal from the environment. Cogent Food Agric. 2020, 6, 1. [Google Scholar] [CrossRef]
  53. Vieira, R.H.S.F.; Volesky, B. Biosorption: A solution to pollution? Int. Microbiol. 2000, 3, 17–24. [Google Scholar] [PubMed]
  54. Mishra, R.; Sinha, V.; Kannan, A.; Upreti, R.K. Reduction of Chromium-VI by Chromium Resistant Lactobacilli: A Prospective Bacterium for Bioremediation. Toxicol. Int. 2012, 19, 25–30. [Google Scholar] [PubMed]
  55. Mishra, A.; Dubey, A.; Shinghal, S. Biosorption of chromium (VI) from aqueous solutions using waste plant biomass. Int. J. Environ. Sci. Technol. 2015, 12, 1415–1426. [Google Scholar] [CrossRef]
  56. Volesky, B.; Holan, Z.R. Biosorption of heavy metals. Biotechnol. Prog. 1990, 11, 235–250. [Google Scholar] [CrossRef]
  57. Malik, A. Metal bioremediation through growing cells. Environ. Int. 2004, 30, 261–278. [Google Scholar] [CrossRef]
  58. Peng, S.H.; Wang, R.; Yang, L.Z.; He, L.; He, X.; Liu, X. Biosorption of copper, zinc, cadmium and chromium ions from aqueous solution by natural foxtail millet shell. Ecotoxicol. Environ. Saf. 2018, 165, 61–69. [Google Scholar] [CrossRef]
  59. Wang, J.; Chen, C. Biosorbents for heavy metals removal and their future. Biotechnol. Adv. 2009, 27, 95–226. [Google Scholar] [CrossRef]
  60. Volesky, B. Biosorption and me. Water Res. 2007, 41, 4017–4029. [Google Scholar] [CrossRef] [PubMed]
  61. Verma, N.; Sharma, R. Bioremediation of Toxic Heavy Metals: A Patent Review. Recent. Pat. Biotechnol. 2017, 11, 171–187. [Google Scholar] [CrossRef] [PubMed]
  62. Ojuederie, O.B.; Babalola, O.O. Microbial and Plant-Assisted Bioremediation of Heavy Metal Polluted Environments: A Review. Int. J. Environ. Res Public Health 2017, 14, 1504. [Google Scholar] [CrossRef] [PubMed]
  63. Zhang, W.; An, Y.; Li, S.; Liu, Z.; Chen, Z.; Ren, Y.; Wang, S.; Zhang, X.; Wang, X. Enhanced heavy metal removal from an aqueous environment using an eco-friendly and sustainable adsorbent. Sci. Rep. 2020, 10, 16453. [Google Scholar] [CrossRef]
  64. Chojnacka, K. Biosorption and bioaccumulation-the prospects for practical applications. Environ. Int. 2010, 36, 299–307. [Google Scholar] [CrossRef]
  65. Tsezos, M.; Remoudaki, E.; Angelatou, V. Biosorption sites of selected metals using Electron microscopy. Comp. Biochem. Phys. A 1997, 118, 481–487. [Google Scholar] [CrossRef]
  66. Duwiejuah, A.B.; Abubakari, A.H.; Quainoo, A.K.; Amadu, Y. Review of Biochar Properties and Remediation of Metal Pollution of Water and Soil. J. Health Pollut. 2020, 10, 200902. [Google Scholar] [CrossRef]
  67. Dias, M.A.; Rosa, C.A.; Linardi, V.R.; Conte, R.A.; De Castro, H.F. Application of factorial design to study of heavy metals biosorption by waste biomass from beverage distillery. Appl. Biochem. Biotechnol. 2001, 91–93, 413–422. [Google Scholar] [CrossRef]
  68. Naja, G.M.; Volesky, B. Treatment of Metal-Bearing Effluents: Removal and Recovery. In Handbook on Heavy Metals in the Environment. Boca Raton; Wang, L.K., Chen, J.P., Hung, Y.T., Shammas, N.K., Eds.; Taylor & Francis: Boca Raton, FL, USA; CRC Press: Boca Raton, FL, USA, 2010; p. 46. [Google Scholar]
  69. Netzahuatl-Muñoz, A.R.; Cristiani-Urbina, M.D.C.; Cristiani-Urbina, E. Chromium Biosorption from Cr(VI) Aqueous Solutions by Cupressus lusitanica Bark: Kinetics, Equilibrium and Thermodynamic Studies. PLoS ONE 2015, 10, e0137086. [Google Scholar] [CrossRef]
  70. Park, D.; Park, J.M.; Yun, Y.S. Mechanisms of the removal of hexavalent chromium by biomaterials or biomaterial-based activated carbons. J. Hazard. Mater. 2006, 137, 1254–1257. [Google Scholar] [CrossRef]
  71. Park, D.; Yun, Y.S.; Park, J.M. Studies on hexavalent chromium biosorption by chemically-treated biomass of Ecklonia sp. Chemosphere 2005, 60, 1356–1364. [Google Scholar] [CrossRef] [PubMed]
  72. Deng, L.; Zhang, Y.; Qin, J.; Wang, X.; Zhu, X. Biosorption of Cr (VI) from aqueous solutions by nonliving algae Cladophora albida. Miner. Eng. 2009, 22, 372–377. [Google Scholar] [CrossRef]
  73. Moghal, A.A.B.; Lateef, M.A.; Mohammed, S.A.S.; Ahmad, M.; Usman, A.R.A.; Almajed, A. Heavy Metal Immobilization Studies and Enhancement in Geotechnical Properties of Cohesive Soils by EICP Technique. Appl. Sci. 2020, 10, 7568. [Google Scholar] [CrossRef]
  74. Khanpour-Alikelayeh, E.; Partovinia, A.; Talebi, A.; Kermanian, H. Enhanced biodegradation of light crude oil by immobilized Bacillus licheniformis in fabricated alginate beads through electrospray technique. Environ. Monit. Assess. 2021, 193, 328. [Google Scholar] [CrossRef]
  75. Pal, D.; Maiti, S.K. An approach to counter sediment toxicity by immobilization of heavy metals using waste fish scale derived biosorbent. Ecotoxicol. Environ. Saf. 2020, 187, 109833. [Google Scholar] [CrossRef]
  76. Bayat, Z.; Hassanshahian, M.; Cappello, S. Immobilization of Microbes for Bioremediation of Crude Oil Polluted Environments: A Mini Review. Open Microbiol. J. 2015, 9, 48–54. [Google Scholar]
  77. Bhattacharya, P.; Banerjee, P.; Mallick, K.; Ghosh, S.; Mukhopadhyay, A.M.; Bandyopadhyay, S. Potential of biosorbent developed from fruit peel of Trewianudiflora for removal of hexavalent chromium from synthetic and industrial effluent: Analyzing phytotoxicity in germinating Vigna seeds. J. Environ. Sci. Health 2013, 48, 706–719. [Google Scholar] [CrossRef]
  78. Sari, A.; Tuzen, M. Biosorption of total chromium from aqueous solution by red algae (Ceramiumvigatum): Equilibrium, kinetics and thermodynamics studies. J. Hazard. Mater. 2008, 160, 349–355. [Google Scholar] [CrossRef]
  79. Hadjmohammadi, M.R.; Salary, M.; Biparva, P. Removal of Cr (VI) from aqueous solution using pine needles powder as a biosorbent. J. Appl. Sci. Environ. Sanit. 2010, 6, 1–13. [Google Scholar]
  80. Nandhagopal, K.; Munuswamy, E.; Krishnan, V. Biosorption of chromium vi by ubiquitous dictyota biomass. Int. J. Pharm. Biol. Sci. 2018, 8, 127–131. [Google Scholar]
  81. Hiew, B.Y.Z.; Lee, L.Y.; Lee, X.J.; Thangalazhy-Gopakumar, S.; Gan, S. Utilisation of environmentally friendly okara-based biosorbent for cadmium(II) removal. Environ. Sci. Pollut. Res. 2021, 28, 40608–40622. [Google Scholar] [CrossRef]
  82. Mahmoud, M.E.; El Zokm, G.M.; Farag, A.E.; Abdelwahab, M.S. Assessment of heat-inactivated marine Aspergillus flavus as a novel biosorbent for removal of Cd(II), Hg(II), and Pb(II) from water. Environ. Sci. Pollut. Res. 2017, 24, 18218–18228. [Google Scholar] [CrossRef]
  83. Serencam, H.; Ozdes, D.; Duran, C.; Tufekci, M. Biosorption properties of Morus alba L. for Cd (II) ions removal from aqueous solutions. Environ. Monit. Assess. 2013, 185, 6003–6011. [Google Scholar] [CrossRef]
  84. Dinh, V.P.; Xuan, T.D.; Hung, N.Q.; Luu, T.T.; Do, T.T.T.; Nguyen, T.D.; Nguyen, V.D.; Anh, T.T.K.; Tran, N.Q. Primary biosorption mechanism of lead (II) and cadmium (II) cations from aqueous solution by pomelo (Citrus maxima) fruit peels. Environ. Sci. Pollut. Res. 2020, 28, 63504–63515. [Google Scholar] [CrossRef]
  85. Liu, L.; Fan, S. Removal of cadmium in aqueous solution using wheat straw biochar: Effect of minerals and mechanism. Environ. Sci. Pollut. Res. 2018, 25, 8688–8700. [Google Scholar] [CrossRef]
  86. Hou, Y.; Cheng, K.; Li, Z.; Ma, X.; Wei, Y.; Zhang, L.; Wang, Y. Biosorption of Cadmium and Manganese Using Free Cells of Klebsiella sp. Isolated from Waste Water. PLoS ONE 2015, 10, e0140962. [Google Scholar] [CrossRef]
  87. Camacho-Chab, J.C.; Castañeda-Chávez, M.D.R.; Chan-Bacab, M.J.; Aguila-Ramírez, R.N.; Galaviz-Villa, I.; Bartolo-Pérez, P.; Lango-Reynoso, F.; Tabasco-Novelo, C.; Gaylarde, C.; Ortega-Morales, B.O. Biosorption of Cadmium by Non-Toxic Extracellular Polymeric Substances (EPS) Synthesized by Bacteria from Marine Intertidal Biofilms. Int. J. Environ. Res. Public Health 2018, 15, 314. [Google Scholar] [CrossRef]
  88. Mahmoudi, E.; Azizkhani, S.; Mohammad, A.W.; Ng, L.Y.; Benamor, A.; Ang, W.L.; Ba-Abbad, M. Simultaneous removal of Congo red and cadmium(II) from aqueous solutions using graphene oxide-silica composite as a multifunctional adsorbent. J. Environ. Sci. 2020, 98, 151–160. [Google Scholar] [CrossRef]
  89. Yu, X.L.; He, Y. Optimal ranges of variables for an effective adsorption of lead(II) by the agricultural waste pomelo (Citrus grandis) peels using Doehlert designs. Sci. Rep. 2018, 8, 729. [Google Scholar] [CrossRef]
  90. Haq, A.U.; Saeed, M.; Anjum, S.; Bokhari, T.H.; Usman, M.; Tubbsum, S. Evaluation of Sorption Mechanism of Pb (II) and Ni (II) onto Pea (Pisum sativum) Peels. J. Oleo Sci. 2017, 66, 735–743. [Google Scholar] [CrossRef]
  91. Rafatullah, M.; Sulaiman, O.; Hashim, R.; Ahmad, A. Adsorption of copper (II), chromium (III), nickel (II) and lead (II) ions from aqueous solutions by meranti sawdust. J. Hazard. Mater. 2009, 170, 969–977. [Google Scholar] [CrossRef] [PubMed]
  92. Yuvaraja, G.; Krishnaiah, N.; Subbaiah, M.V.; Krishnaiah, A. Biosorption of Pb(II) from aqueous solution by Solanum melongena leaf powder as a low-cost biosorbent prepared from agricultural waste. Colloids Surf. B Biointerfaces 2014, 114, 75–81. [Google Scholar] [CrossRef] [PubMed]
  93. Sarada, B.; Prasad, M.K.; Kumar, K.K.; Murthy, C.H.V. Potential use of leaf biomass, Araucaria heterophylla for removal of Pb+2. Int. J. Phytoremediation 2013, 15, 756–773. [Google Scholar] [CrossRef] [PubMed]
  94. Yang, J.; Hou, B.; Wang, J.; Tian, B.; Bi, J.; Wang, N.; Li, X.; Huang, X. Nanomaterials for the Removal of Heavy Metals. Nanomaterials 2019, 9, 424. [Google Scholar] [CrossRef]
  95. Ahmed, S.; Ahmad, M.; Swami, B.L.; Ikram, S. A review on plants extract mediated synthesis ofsilver nanoparticles for antimicrobial applications:A green expertise. J. Adv. Res. 2016, 7, 17–28. [Google Scholar] [CrossRef] [Green Version]
  96. Khan, I.; Saeed, K.; Khan, I. Nanoparticles: Properties, applications and toxicities. Arab. J. Chem. 2019, 12, 908–931. [Google Scholar] [CrossRef]
  97. Vidu, R.; Matei, E.; Predescu, A.M.; Alhalaili, B.; Pantilimon, C.; Tarcea, C.; Predescu, C. Removal of Heavy Metals from Wastewaters: A Challenge from Current Treatment Methods to Nanotechnology Applications. Toxics 2020, 8, 101. [Google Scholar] [CrossRef]
  98. Christopher, F.C.; Anbalagan, S.; Kumar, P.S.; Pannerselvam, S.R.; Vaidyanathan, V.K. Surface adsorption of poisonous Pb(II) ions from water using chitosan functionalised magnetic nanoparticles. IET Nanobiotechnol. 2017, 11, 433–442. [Google Scholar] [CrossRef]
  99. Farghali, A.A.; Bahgat, M.; Enaiet Allah, A.; Khedr, M.H. Adsorption of Pb(II) ions from aqueous solutions using copper oxide nanostructures. Beni-Suef Univ. J. Basic Appl. Sci. 2013, 2, 61–71. [Google Scholar] [CrossRef]
  100. Wang, C.; Fan, X.; Wang, P.; Hou, J.; Ao, Y.; Miao, L. Adsorption behavior of lead on aquatic sediments contaminated with cerium dioxide nanoparticles. Environ. Pollut. 2016, 219, 416–424. [Google Scholar] [CrossRef]
  101. Khanna, M.; Mathur, A.; Dubey, A.K.; McLaughlin, J.; Moirangthem, I.; Wadhwa, S.; Singh, D.; Kumar, R. Rapid removal of lead(II) ions from water using iron oxide-tea waste nanocomposite—A kinetic study. IET Nanobiotechnol. 2020, 14, 275–280. [Google Scholar] [CrossRef]
  102. Zhang, Y.; Su, Y.; Zhou, X.; Dai, C.; Keller, A.A. A new insight on the core-shell structure of zerovalent iron nanoparticles and its application for Pb(II) sequestration. J. Hazard. Mater. 2013, 2, 685–693. [Google Scholar] [CrossRef]
  103. Li, Z.; Gong, Y.; Zhao, D.; Dang, Z.; Lin, Z. Enhanced removal of zinc and cadmium from water using carboxymethyl cellulose-bridged chlorapatite nanoparticles. Chemosphere 2021, 263, 128038. [Google Scholar] [CrossRef]
  104. Koju, N.K.; Song, X.; Wang, Q.; Hu, Z.; Colombo, C. Cadmium removal from simulated groundwater using alumina nanoparticles: Behaviors and mechanisms. Environ. Pollut. 2018, 240, 255–266. [Google Scholar] [CrossRef]
  105. Devi, V.; Selvaraj, M.; Selvam, P.; Kumar, A.A.; Sankara, S.; Dinakaran, K. Preparation and characterization of CNSR functionalized Fe3O4 magnetic nanoparticles: An efficient adsorbent for the removal of cadmium ion from water. J. Environ. Chem. Eng. 2017, 5, 4539–4546. [Google Scholar] [CrossRef]
  106. Diep, P.; Mahadevan, R.; Yakunin, A.F. Heavy Metal Removal by Bioaccumulation Using Genetically Engineered Microorganisms. Front. Bioeng. Biotechnol. 2018, 6, 157. [Google Scholar] [CrossRef]
  107. Deng, S.; Yu, Q.; Huang, J.; Yu, G. Removal of perfluorooctane sulfonate from wastewater by anion exchange resins: Effects of resin properties and solution chemistry. Water Res. 2010, 18, 5188–5195. [Google Scholar] [CrossRef]
  108. Timkova, I.; Sedláková-Kaduková, J.; Pristaš, P. Biosorption and Bioaccumulation Abilities of Actinomycetes/Streptomycetes Isolated from Metal Contaminated Sites. Separations 2018, 5, 54. [Google Scholar] [CrossRef]
  109. Ahluwalia, S.S. Microbial removal of hexavalent chromium and scale up potential. Int. J. Curr. Microbiol. Appl. Sci. 2014, 3, 383–398. [Google Scholar]
  110. Ali, H.; Khan, E.; Ilahi, I. Environmental Chemistry and Ecotoxicology of Hazardous Heavy Metals: Environmental Persistence, Toxicity, and Bioaccumulation. J. Chem. 2019, 2019, 6730305. [Google Scholar] [CrossRef]
  111. Yilmazer, P.; Saracoglu, N. Bioaccumulation and biosorption of copper (II) and chromium (III) from aqueous solutions by Pichia stipitis yeast. J. Chem. Technol. Biotechnol. 2009, 84, 604–610. [Google Scholar] [CrossRef]
  112. Jacob, J.M.; Karthik, C.; Saratale, R.G.; Kumar, S.S.; Prabakar, D.; Kadirvelu, K.; Pugazhendhi, A. Biological approaches to tackle heavy metal pollution: A survey of literature. J. Environ. Manag. 2018, 217, 56–70. [Google Scholar] [CrossRef] [PubMed]
  113. El-Naggar, N.E.; El-Khateeb, A.Y.; Ghoniem, A.A.; El-Hersh, M.S.; Saber, W.I.A. Innovative low-cost biosorption process of Cr6+ by Pseudomonas alcaliphila NEWG-2. Sci. Rep. 2010, 10, 14043–14061. [Google Scholar] [CrossRef] [PubMed]
  114. Tekerlekopoulou, A.G.; Tsiflikiotou, M.; Akritidou, L.; Viennas, A.; Tsiamis, G.; Pavlou, S.; Bourtzis, K.; Vayenas, D.V. Modelling of biological Cr (VI) removal in draw-fill reactors using microorganisms in suspended and attached growth systems. Water Res. 2013, 47, 623–636. [Google Scholar] [CrossRef]
  115. Humphries, A.C.; Nott, K.P.; Hall, L.D.; Macaskie, L.E. Reduction of Cr (VI) by immobilized cells of Desulfovibrio vulgaris NCIMB 8303 and Microbacterium sp. NCIMB 13776. Biotechnol. Bioeng. 2005, 90, 589–596. [Google Scholar] [CrossRef]
  116. Ibrahim, A.S.S.; El-Tayeb, A.M.; Elbadawi, B.Y.; Al-Salamah, A.A.; Antranikian, G. Hexavalent chromate reduction by alkaliphilic Amphibacillus sp. KSUCr3 is mediated by copper-dependent membrane-associated Cr (VI). Extremophiles 2012, 16, 659–668. [Google Scholar] [CrossRef]
  117. Liu, Z.; Wu, Y.; Lei, C.; Liu, P.; Gao, M. Chromate reduction by a chromate-resistant bacterium Microbacterium sp. World J. Microbiol. Biotechnol. 2012, 28, 1585–1592. [Google Scholar] [CrossRef]
  118. Henson, M.W.; Santo Domingo, J.W.; Kourtev, P.S.; Jensen, R.V.; Dunn, J.A.; Learman, D.R. Metabolic and genomic analysis elucidates strain-level variation in Microbacterium spp. isolated from chromate contaminated sediment. PeerJ 2015, 3, 1395–1412. [Google Scholar] [CrossRef]
  119. Pattanapipitpaisal, P.; Brown, N.L.; Macaskie, L.E. Chromate reduction and 16S rRNA identification of bacteria isolated from a Cr (VI)-contaminated site. Appl. Microbiol. Biotechnol. 2001, 57, 257–261. [Google Scholar]
  120. Ahemad, M. Enhancing phytoremediation of chromium-stressed soils through plant-growth-promoting bacteria. J. Genet. Eng. Biotechnol. 2015, 13, 51–58. [Google Scholar] [CrossRef]
  121. Kubrak, O.I.; Lushchak, O.V.; Lushchak, J.V.; Torous, I.M.; Storey, J.M.; Storey, K.B.; Lushchak, V.I. Chromium effects on free radical processes in goldfish tissues: Comparison of Cr (III) and Cr (VI) exposures on oxidative stress markers, glutathione status and antioxidant enzymes. Comp. Biochem. Physiol. C Toxicol. Pharmacol. 2010, 152, 360–370. [Google Scholar] [CrossRef] [PubMed]
  122. Kumar, M.S.; Praveenkumar, R.; Ilavarasi, A.; Rajeshwari, K.; Thajuddin, N. Biochemical changes of fresh water cyanobacteria Dolichospermum flos-aquae NTMS07 to chromium-induced stress with special reference to antioxidant enzymes and cellular fatty acids. Bull. Environ. Contam. Toxicol. 2013, 90, 730–735. [Google Scholar] [CrossRef] [PubMed]
  123. Joutey, N.T.; Sayel, H.; Bahafid, W.; El Ghachtouli, N. Mechanisms of hexavalent chromium resistance and removal by microorganisms. Rev. Environ. Contam. Toxicol. 2015, 233, 45–69. [Google Scholar] [PubMed]
  124. Zahoor, A.; Rehman, A. Isolation of Cr (VI) reducing bacteria from industrial effluents and their potential use in bioremediation of chromium containing wastewater. J. Environ. Sci. 2009, 21, 814–820. [Google Scholar] [CrossRef]
  125. Balamurugan, D.; Udayasooriyan, C.; Kamaladevi, B. Chromium (VI) reduction by Pseudomonas putida and Bacillus subtilis isolated from contaminated soils. Int. J. Environ. Sci. 2014, 5, 522–529. [Google Scholar]
  126. Srivastava, S.; Thakur, I.S. Evaluation of biosorption potency of Acinetobacter sp. for removal of hexavalent chromium from tannery effluent. Biodegradation 2017, 18, 637–646. [Google Scholar] [CrossRef]
  127. Mwandira, W.; Nakashima, K.; Kawasaki, S.; Arabelo, A.; Banda, K.; Nyambe, I.; Chirwa, M.; Ito, M.; Sato, T.; Igarashi, T.; et al. Biosorption of Pb (II) and Zn (II) from aqueous solution by Oceanobacillus profundus isolated from an abandoned mine. Sci. Rep. 2020, 10, 21189. [Google Scholar] [CrossRef]
  128. Ma, Y.; Wang, P.; Wang, C.; Zhang, S.H.; Cheng, S. Isolation and characterization of pb-resistant strains and the removal of Pb(II). Fresenius Environ. Bull. 2015, 24, 1150–1157. [Google Scholar]
  129. Mohseni, M.; Khosravi, F.; Mohajerani, M.; Chaichi, M.J. Bioremediation Activity of Pb (II) Resistance Citrobacter sp. MKH2 Isolated from Heavy Metal Contaminated Sites in Iran. J. Sci. Islam. Repub. Iran 2014, 25, 105–110. [Google Scholar]
  130. Heidari, P.; Panico, A. Sorption Mechanism and Optimization Study for the Bioremediation of Pb(II) and Cd(II) Contamination by Two Novel Isolated Strains Q3 and Q5 of Bacillus sp. Int. J. Environ. Res. Public Health 2020, 17, 4059. [Google Scholar] [CrossRef]
  131. Wang, J.; Liu, X.; Wang, H.; Hu, H.; Pang, L.; Huang, B.; Zhu, R. Isolation, identification and heavy metals biosorption of a lead and cadmium-tolerant strain. Sheng Wu Gong Cheng Xue Bao 2020, 36, 1600–1609. [Google Scholar] [PubMed]
  132. Chen, H.; Zhong, C.; Berkhouse, H.; Zhang, Y.; Lv, Y.; Lu, W.; Yang, Y.; Zhou, J. Removal of cadmium by bioflocculant produced by Stenotrophomonas maltophilia using phenol-containing wastewater. Chemosphere 2016, 155, 163–169. [Google Scholar] [CrossRef] [PubMed]
  133. Choinska-Pulit, A.; Sobolczyk-Bednarek, J.; Łaba, W. Optimization of copper, lead and cadmium biosorption onto newly isolated bacterium using a Box-Behnken design. Ecotoxicol. Environ. Saf. 2018, 149, 275–283. [Google Scholar] [CrossRef]
  134. Saravanan, A.; Jayasree, R.; Hemavathy, R.V.; Jeevanantham, S.; Hamsini, S.; Senthil Kumar, P.; Yaashikaa, P.R.; Manivasagan, V.; Yuvaraj, D. Phytoremediation of Cr(VI) ion contaminated soil using Black gram (Vigna mungo): Assessment of removal capacity. J. Environ. Chem. Eng. 2019, 7, 103052. [Google Scholar] [CrossRef]
  135. Chen, R.; Sheehan, T.; Ng, J.L.; Brucksa, M.; Su, X. Capacitive deionization and electrosorption for heavy metal removal. Environ. Sci. Water Res. Technol. 2020, 6, 258–282. [Google Scholar] [CrossRef]
  136. Singh, N.; Singh, V.; Rai, S.N.; Vamanu, E.; Singh, M.P. Metagenomic Analysis of Garden Soil-Derived Microbial Consortia and Unveiling Their Metabolic Potential in Mitigating Toxic Hexavalent Chromium. Life 2022, 12, 2094. [Google Scholar] [CrossRef] [PubMed]
  137. Pandey, L.K.; Bergey, E.A. Exploring the status of motility, lipid bodies, deformities and size reduction in periphytic diatom community from chronically metal (Cu, Zn) polluted waterbodies as a biomonitoring tool. Sci. Total. Environ. 2016, 550, 372–381. [Google Scholar] [CrossRef] [PubMed]
  138. Kiran Marella, T.; Saxena, A.; Tiwari, A. Diatom mediated heavy metal remediation: A review. Bioresour. Technol. 2020, 305, 123068. [Google Scholar] [CrossRef]
  139. Renu.; Agarwal, M.; Singh, K. Heavy metal removal from wastewater using various adsorbents: A review. J. Water Reuse. Desalin 2017, 7, 387–419. [Google Scholar] [CrossRef]
  140. Elbasiouny, H.; Darwesh, M.; Elbeltagy, H.; Abo-Alhamd, F.G.; Amer, A.A.; Elsegaiy, M.A.; Khattab, I.A.; Elsharawy, E.A.; Ebehiry, F.; El-Ramady, H.; et al. Ecofriendly remediation technologies for wastewater contaminated with heavy metals with special focus on using water hyacinth and black tea wastes: A review. Environ. Monit. Assess. 2021, 193, 449. [Google Scholar] [CrossRef]
  141. Borozan, A.B.; Misca, C.D.; Morar, A.; Obistioiu, D.; Raba, D.N.; Pirvulescu, L.; Caba, I.L.; Alexa, E.; Poiana, M.A.; Bordean, D.M.; et al. Soil pollution with heavy metals and bioremediation methods. AgroLife Sci. J. 2021, 10, 54–66. [Google Scholar] [CrossRef]
Toxics 11 00147 g001 550
Figure 1. Toxicity of heavy metal ions.
Figure 1. Toxicity of heavy metal ions.
Toxics 11 00147 g001
Toxics 11 00147 g002 550
Figure 2. Bacterial-mediated Cr (VI) remediation and the mechanism of Cr (VI) reduction in the bacterial cell.
Figure 2. Bacterial-mediated Cr (VI) remediation and the mechanism of Cr (VI) reduction in the bacterial cell.
Toxics 11 00147 g002
Table
Table 1. Maximum dischargeable limits for heavy metals in industrial effluent [27].
Table 1. Maximum dischargeable limits for heavy metals in industrial effluent [27].
Heavy MetalsCPCB, 2000 (Dischargeable Limit in Industrial Effluent)
Cr (VI)1.00–2.00 mg/L
Cd (II)0.20–2.00 mg/L
Pb (II)0.10 mg/L
Table
Table 2. The maximum allowable limit of heavy metal ions in drinking water [28,29].
Table 2. The maximum allowable limit of heavy metal ions in drinking water [28,29].
Heavy MetalsUS EPA, 2018 WHO, 2011
Cr (total) (mg/L)0.10 mg/L0.05
Cd (II) (mg/L)0.005 mg/L0.003
Pb (II) (mg/L)0.015 mg/L0.01
Table
Table 3. Cr (VI) removal by microbial and plant-based biomasses, and Cr (VI) biosorption capacity.
Table 3. Cr (VI) removal by microbial and plant-based biomasses, and Cr (VI) biosorption capacity.
BiosorbentBiosorption Capacity
(mg/g)		pHTemperature (°C)Biosorbent Dose
(g/L)		Initial Concentration (mg/L)Reference
Trewia nudiflorafruit peel powder294.121–2200.7522–248[77]
Ceramium virgatumdry biomass26.51.5201010[78]
Pine needle powder482–3251050[79]
Dictyota dichotomabiomass9.024272040[80]
Cupressus lusitanicaBark305.41.52810100[69]
Table
Table 4. Cd (II) removal using microbial and plant-based biomass.
Table 4. Cd (II) removal using microbial and plant-based biomass.
BiosorbentBiosorption Capacity
(mg/g)		pHTemperature (°C)Reference
Okara waste14.806.270[81]
Foxtail millet shell12.48525[58]
Heat-inactivated marine Aspergillus flavus 174.25720[82]
Morus alba L. pomace21.69640[83]
Pomelo fruit peel13.355.530[84]
Wheat straw biochar69.80525[85]
Klebsiella sp. biomass170.4530[86]
Extracellular Polymeric Substances (EPS) synthesized by microbactan97728[87]
Table
Table 5. Pb (II) biosorption capacity of different plant- and microbial-biomass-based biosorbents.
Table 5. Pb (II) biosorption capacity of different plant- and microbial-biomass-based biosorbents.
BiosorbentBiosorption Capacity (mg/g)pHTemperature (°C)Reference
Heat-inactivated marine Aspergillus flavus 207.2620[88]
Pomelo fruit peel47.185.530[84]
Citrus grandis peels2.13350[89]
Pea (Pisum sativum) peels140.84630[90]
Meranti sawdust34.24630[91]
Solanum melongena leaves71.42540[92]
Araucaria heterophylla (green plant) biomass9.64530[93]
Table
Table 6. Nanomaterials and their heavy metal adsorption capacity.
Table 6. Nanomaterials and their heavy metal adsorption capacity.
Nanoparticles/NanocompositesHeavy MetalsBiosorption Capacity
(mg/g)		pHTemperature (°C)Reference
Chitosan-functionalized magnetic nanoparticlesPb (II)498.6630[98]
CuO nanostructuresPb (II)115–1256.5--[99]
Cerium dioxide nanoparticles (CeO2 NPs)Pb (II)4.996.830[100]
Iron oxide–tea waste nanocompositePb (II)18.83--25[101]
Nanoscale zerovalent iron (nZVI)Pb (II)16674.535[102]
Carboxymethyl cellulose bridged chlorapatite nanoparticlesCd (II)150.27--[103]
Alumina nanoparticlesCd (II)24.20827[104]
CNSR-coated magnetic nanoparticlesCd (II)54.61030–50[105]
Oxide–silica compositeCd (II)43.45650[88]
Table
Table 7. Bacterial species and their Cr (VI) removal efficiency.
Table 7. Bacterial species and their Cr (VI) removal efficiency.
BacteriaRemoval Efficiency
(%)		Optimum pHOptimum TemperatureInitial Cr (VI) Concentration (mg/L)Reference
Staphylococcus capitis89737--[124]
Bacillussp. JDM-2-186637--[124]
Bacillus subtilis
(Bacteria)		95.19737--[125]
Acinetobactersp.75775--[126]
Table
Table 8. Pb (II) removal efficiency of bacterial strains.
Table 8. Pb (II) removal efficiency of bacterial strains.
BacteriaRemoval Efficiency
(%)		Optimum pHOptimum TemperatureInitial Pb(II) Concentration (mg/L)Reference
Oceanobacillus profundus KBZ 3-29763050[127]
Acinetobacter sp. strain THKPS1671.253535[128]
Citrobacter sp. Strain MKH295.06-3080[129]
Bacillus sp. Strain Q393.85.838.8115.4[130]
Bacillus sp. Strain Q376.46.234.3127.4[130]
Table
Table 9. Cd (II) removal efficiency of bacterial strains.
Table 9. Cd (II) removal efficiency of bacterial strains.
BacteriaRemoval Efficiency
(%)		Optimum pHOptimum TemperatureInitial Cd (II) Concentration (mg/L)Reference
Bacillus sp. Strain Q358538.650.6[130]
Bacillus sp. Strain Q378538.350[130]
Cedecea sp. strain SC1951737120[131]
Stenotrophomonas maltophilia ZZC-0681.43%63010[132]
Pseudomonas azotoformans strain JAW144.6763025[133]
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Singh, V.; Singh, N.; Rai, S.N.; Kumar, A.; Singh, A.K.; Singh, M.P.; Sahoo, A.; Shekhar, S.; Vamanu, E.; Mishra, V. Heavy Metal Contamination in the Aquatic Ecosystem: Toxicity and Its Remediation Using Eco-Friendly Approaches. Toxics 2023, 11, 147. https://doi.org/10.3390/toxics11020147

AMA Style

Singh V, Singh N, Rai SN, Kumar A, Singh AK, Singh MP, Sahoo A, Shekhar S, Vamanu E, Mishra V. Heavy Metal Contamination in the Aquatic Ecosystem: Toxicity and Its Remediation Using Eco-Friendly Approaches. Toxics. 2023; 11(2):147. https://doi.org/10.3390/toxics11020147

Chicago/Turabian Style

Singh, Veer, Nidhi Singh, Sachchida Nand Rai, Ashish Kumar, Anurag Kumar Singh, Mohan P. Singh, Ansuman Sahoo, Shashank Shekhar, Emanuel Vamanu, and Vishal Mishra. 2023. "Heavy Metal Contamination in the Aquatic Ecosystem: Toxicity and Its Remediation Using Eco-Friendly Approaches" Toxics 11, no. 2: 147. https://doi.org/10.3390/toxics11020147

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