The purpose of the study was to review the most recent findings related to lead toxicity for plants, animals and humans. It is stated that the highest potential belongs to biological techniques and the most up-to-date lead phytoremediation technologies. Results and discussion. Lead is one of the most toxic heavy metals which frequently occurs in the environment. Various quantitative indices are used to assess lead toxicity at trophic levels of a food chain, including the levels of lead absorption by plants. Hyperaccumulating plants can accumulate more than 1000 mg/kg of the metal. Higher lead concentrations are connected with fruit plants. Lead transport in animals is done through the blood circulatory system, whereby bones are the main lead absorbers (~ 90%), where lead replace calcium and reduces the bone mineral density. Lead poisoning in humans most frequently results from peroral intake and absorption through the gastrointestinal tract. The main process of lead transport from the gastrointestinal tract to various body tissues is conducted via erythrocytes, where lead binds to hemoglobin. The half-life of lead in blood and soft tissues has been estimated as 35 and 40 days, respectively. Lead may stay in the bones up to 30 years; its concentration rate in the teeth and bones increases with age. Over 95% of lead deposit in the skeleton represent an insoluble phosphate. The biological half-life of lead in children is significantly larger than in adults. The total lead load on skeleton makes 80-95% in adults and around 73% in children. Lead toxicity primarily targets the human central nervous system, and child exposure to high amounts of lead from the environment, particularly in the case of anemia, entails low intelligence and movement disorders. Mothers can transmit lead to fetus or infants during breast-feeding. There are various processes that seek to reduce the overall lead concentration and accumulation in the food chain. Out of those, the most effective are biological techniques of lead remediation from contaminated resources. They include phytoremediation and microbiological treatment. The first option reduces lead mobility in the root zone of plants through complex formation. The second option reduces lead availability in the environment via employing local microorganisms. Both options are a natural, safe, efficient, and environmentally friendly technology which implies cost-effective operation and represents no threat to the environment and health. However, a high potential is detected in biotechnological and genetic approaches, such as genomics, metagenomics, metabolomics, proteomics, transcriptomics, nanoparticles, and isotope probing. These are the most up-to-date technologies for lead phytoremediation. The use of omics approaches implies identifying candidate genes for an efficient lead removal, diverse phylogenetic research into the sequence of genes and proteins that control lead bioremediation and genetically modified plants cultivation via transgenesis, which are able to restore various wastewaters, contaminated lands, and can be beneficial for practical application in bioremediation. Conclusion. The most recent research and development in the field of nanosciences provide access to even more efficient and stable approaches to remediation that are being successfully applied in cleaning soils, deposits, solid waste, and wastewaters

Keywords: lead toxicity, food chains, remediation techniques

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1. Kumar A, Kumar A, Cabral-Pinto MMS, Chaturvedi AK, Shabnam AA, et al. Lead Toxicity: Health Hazards, Influence on Food Chain, and Sustainable Remediation Approaches. Int J Environment Res Public Health. 2020;17(7):2179. PMID: 32218253. PMCID: PMC7177270. https://doi.org/10.3390/ijerph17072179
2. Emsley J. Nature's Building Blocks: An AZ Guide to the Elements. Oxford UK: Oxford University Press; 2011.
3. CDC. Advisory Committee on Childhood Lead Poisoning Prevention (ACCLPP). London UK: Jessica Kingsley Publishers; 2012.
4. Maestri E, Marmiroli M, Visioli G, Marmiroli N. Metal tolerance and hyperaccumulation: Costs and trade-offs between traits and environment. Environment Exp Botany J. 2010;68:1-13. https://doi.org/10.1016/j.envexpbot.2009.10.011
5. Wojas S, Ruszczynska A, Bulska E, Wojciechowski M, Antosiewicz DM. Ca2+-dependent plant response to Pb2+ is regulated by LCT1. Environment Pollution. 2007;147:584-592. PMID: 17140712. https://doi.org/10.1016/j.envpol.2006.10.012
6. Rai PK, Lee SS, Zhang M, Tsang YF, Kim KH. Heavy metals in food crops: Health risks, fate, mechanisms, and Management. Environment Int J. 2019;125:365-385. PMID: 30743144. https://doi.org/10.1016/j.envint.2019.01.067
7. Theppeang K, Glass TA, Bandeen-Roche K, Todd A.C, Rohde CA, Links JM, et al. Associations of Bone Mineral Density and Lead Levels in Blood, Tibia, and Patella in Urban-Dwelling Women. Environment Health Perspectives. 2008;116:784-790. PMID: 18560535. PMCID: PMC2430235. https://doi.org/10.1289/ehp.10977
8. Rahman S, Joshi MV. Effect of lead toxicity on growth and performance of broilers. Tamilnadu J Vet Animal Sci. 2009;5:59-62.
9. Kabata-Pendias A, Szteke B. Trace Elements in Abiotic and Biotic Environments. FL, USA: CRC Press Boca Raton; 2015. https://doi.org/10.1201/b18198
10. Concha G, Eneroth H, Hallstrom H, Sand S. Contaminants and Minerals in Foods for Infants and Young Children. Uppsala, Sweden: National Food Agency; 2013. p. 22.
11. World Health Organisation (WHO). Childhood Lead Poisoning. Geneva, Switzerland: WHO; 2010. 71 p.
12. Wani AL, Ara A, Usmani JA. Lead toxicity: A review. Interdisciplinary Toxicology. 2015;8:55-64. PMID: 27486361. PMCID: PMC4961898. https://doi.org/10.1515/intox-2015-0009
13. Bellinger DC, Malin A, Wright RO. The Neurodevelopmental Toxicity of Lead: History, Epidemiology, and Public Health Implications. Adv Neurotoxicol. 2018;2:1-26. https://doi.org/10.1016/bs.ant.2018.03.009
14. World Health Organisation (WHO) Safety evaluation of certain food additives and contaminants. Available from: https://apps.who.int/iris/bitstream/handle/10665/44515/WHO_TRS_960_eng.pdf;jsessionid=AFB1D9565016562EA09FFBFF1734B190?sequence=1
15. Yuan G, Dai S, Yin Z, Lu H, Jia R, Xu J, et al. Toxicological assessment of combined lead and cadmium: Acute and sub-chronic toxicity study in rats. Food Chem Toxicol. 2014;65:260-268. PMID: 24394482. https://doi.org/10.1016/j.fct.2013.12.041
16. Carocci A, Catalano A, Lauria G, Sinicropi MS, Genchi G. Lead toxicity, antioxidant defense and environment. Rev Environ Contam Toxicol. 2016;238:45-67. PMID: 26670034. https://doi.org/10.1007/398_2015_5003
17. International Agency for Research on Cancer (IARC) Agents. IARC Monographs on the Evaluation of Carcinogenic Risks to Humans. Vol 1-121. Lyon, France: IARC Monographs; 2018. p. 1-25.
18. Gong Y, Zhao D, Wang Q. An overview of field-scale studies on remediation of soil contaminated with heavy metals and metalloids: Technical progress over the last decade. Water Research J. 2018;147:440-460. PMID: 30343201. https://doi.org/10.1016/j.watres.2018.10.024
19. Cheng SF, Huang CY, Chen KL, Lin SC, Lin YC. Phytoattenuation of lead-contaminated agricultural land using Miscanthusfloridulus-An in situ case study. Desalination and Water Treatment. 2016;57:7773-7779. https://doi.org/10.1080/19443994.2015.1033477
20. Kumar A, Prasad MNV. Transgenic Plant Technology for Remediation of Toxic Metals and Metalloids. Plant genetic engineering approach for the Pb and Zn remediation: Defense reactions and detoxification mechanisms. Elsevier; San Diego, CA, USA: 2019. Vol 17. p. 359-380. PMCID: PMC6872759. https://doi.org/10.1016/B978-0-12-814389-6.00017-1
21. Kumar S, Prasad S, Yadav KK, Shrivastava M, Gupta N, Nagar S, et al. Hazardous heavy metals contamination of vegetables and food chain: Role of sustainable remediation approaches. Environ Res. 2019;179:108792. PMID: 31610391. https://doi.org/10.1016/j.envres.2019.108792
22. Adeleye AS, Conway JR, Garner K, Huang Y, Su Y. Engineered nanomaterials for water treatment and remediation: Costs, benefits, and applicability. Chemical Engineering J. 2016;286:640-662 https://doi.org/10.1016/j.cej.2015.10.105
23. Yadav KK, Singh JK, Gupta N, Kumar V. A review of nanobioremediation technologies for environmental cleanup: A novel biological approach. J Materials and Environ Sci. 2017;8:740-757.