Ecological Risks of Heavy Metals Found in Soils at Informal E-Waste Processing Sites in Nigeria

  • Adedoyin Bankole
  • Akinyemi Ogunkeyede
  • Hien Ngo
  • Li Liang
  • Harrison Agboro
  • Khadijah Isimekhai
  • Ekaette Fadairo
  • Gospel Isangadighi
  • Efe Isukuru
  • Charles Ogbodhu
Keywords: heavy metals, ecological risk assessment, e-waste, Alaba international Market, soil contamination


This study aimed to assess the levels of six heavy metals (Pb, Zn, Cu, Cr, Cd, Ni) in surface soils collected from five informal e-waste processing sites at Alaba International Market Lagos State. A total of 25 soil samples from distinct locations were analyzed for these metals following digestion through standard methods, subsequently estimating their ecological risks. Concentration ranges of heavy metals (mg/kg) in e-waste processing site soils were: Zn (148–12852) > Cu (24.1–23174) > Pb (18.5–8611) > Ni (12.0–158) > Cr (6.5–36.8) > Cd (0.5–37.1), distinct from reference soils' metal ranges: Ni (10.2–11.6), Zn (8.8–11.5), Pb (7.5–10.6), Cu (4.8–12.7), Cr (0.2–11.8), Cd (1.01–2.10). Heavy metal concentrations in e-waste site soils significantly exceeded control levels. Elevated concentrations, except for Cd in S3, were observed in S2, S3, and S5 compared to S1 and S4. Ecological risk index demonstrated higher risk in S3 than S2, and geo-accumulation index identified extreme pollution in S2, S3, and S4. The study also revealed strong positive linear relationships among specific heavy metals, implying potential co-exposure risks. This highlights the need for the comprehensive development of effective remediation strategies to mitigate the release of heavy metals from informal e-waste processing sites at the Alaba International Market to prevent them from risking Nigeria’s environment.


[1] StEP Initiative. 2015. Annual Global Report on Electrical Electronic Waste. United Nations University, Bonn
[2] Lines K, Garside B, Sinha S, Fedorenko I. 2016. Clean and inclusive?: Recycling e-waste in China and India. International Institute for Environment and Development. IIED, London. p. 24-30.
[3] Balde CP, Forti V, Gray V, Kuehr R. Stegmann P. 2017. The global e-waste monitor-united Nations University (UNU), International Telecommunication Union (ITU), and International Solid Waste Association (ISWA), Bonn/Geneva/Vienna.
[4] Rawat, S., Verma, L., & Singh, J. 2020. Environmental hazards and management of E-waste. Environmental Concerns and Sustainable Development: Volume 2: Biodiversity, Soil and Waste Management, 381-398.
[5] Pickren G. 2014. Political ecologies of electronic waste: uncertainty and legitimacy in the governance of e-waste geographies. Environment and Planning. 46(1):26–45.
[6] International Labour Organization (ILO). 2019. Decent work in the management of electrical and electronic waste (e-waste). ISBN 978-92-2-1330790
[7] Forti V, Baldé CP, Kuehr R, Bel G, Monitor GEW. 2020. Quantities flow and the circular economy potential. The Global E-waste Monitor. 2020:13-15.
[8] Zhang KS. 2020a. Turning Trash into Treasure- A Comparative Study of E-waste Recycling in China and the US through Systems Thinking (Doctoral dissertation). Virginia Polytechnic Institute and State University. Available at: https://karenszhang. com/wp-content/uploads/2020/11/Turning-Trash-Into-Treasure. pdf. (Accessed: 9 November 2022).
[9] Jiang B, Adebayo A, Jia J, Xing Y, Deng S, Deng S, Guo L, Liang Y, Zhang D. 2019. Impacts of heavy metals and soil properties at a Nigerian e-waste site on soil microbial community. Journal of hazardous materials. 362:187-195.
[10] Otache MY, Musa JJ, Animashaun IM, Oji DM. 2014. Evaluation of the Effects of Electronic Waste on Topsoil and Groundwater. International Journal of Science, Engineering and Technology Research. 3:3469-347.
[11] Awoniyi MA. 2016. The Emergence of Common Market in West Africa: An Examination of Cross Culture and Ethnographic Marketing System of Alaba International Market, Lagos-Nigeria. American Journal of Industrial and Business Management. 6:136-154.
[12] Lebbie TS, Moyebi OD, Asante KA, Fobil J, Brune-Drisse MN, Suk WA, Sly PD, Gorman J, Carpenter DO. 2021. E-Waste in Africa: A Serious Threat to the Health of Children. International journal of environmental research and public health. 18(16):8488.
[13] Puckett J, Smith T. 2002. Exporting harm: the high-tech trashing of Asia. The Basel Action Network. Silicon Valley Toxics Coalition, Seattle.
[14] Brigden K, Labunska I, Santillo D, Allsopp M. 2005. Recycling of electronic wastes in China and India: workplace and environmental contamination. Greenpeace Research Laboratories Technical Note 09/2005, Publ. Greenpeace International. 56:47.
[15] Huo X, Peng L, Xu X, Zheng L, Qiu B, Qi Z, Zhang B, Han D, Piao Z. 2007. Elevated blood lead levels of children in Guiyu, an electronic waste recycling town in China. Environ Health Perspect. 115(7):1113-7. DOI: https://doi. org/10.1289/ehp.9697.
[16] Gawade A, Deshmukh P, Shivankar V, Gavali L. 2016. Analysis of Roadside Dust for Heavy Metal Pollutants in Navi Mumbai. International Journal of Engineering Technology, Management and Applied Sciences. 4(7):80–88.
[17] Owoso O, Osibanjo O, Nnorom IC. 2018. Assessment of heavy metal contents of end-of-life computer monitor cathode tubes and plastic casings. Journal of applied science and environmental management. 22(3):400-405.
[18] Alabi OA, Bakare AA, Xu X, et al. 2012. Comparative evaluation of environmental contamination and DNA damage induced by electronic-waste in Nigeria and China. Science of The Total Environment. 423:62-72. doi:10.1016/j.scitotenv.2012.01.056
[19] Bankole AO. 2018. Heavy metal determination and ecological risk assessment of informal e-waste processing in Alaba international market, Lagos, Nigeria. [Ph.D. thesis]. University of Ibadan, Nigeria.
[20] Ouabo RE, Ogundiran MB, Sangodoyin AY, Babalola BA. 2019. Ecological risk and human health implications of heavy metals contamination of surface soil in e-waste recycling sites in Douala, Cameroun. J. Health Pollut. 9:190310.
[21] Moeckel C, Breivik K, Nøst TH, Sankoh A, Jones KC, Sweetman A. 2020. Soil pollution at a major West African E-waste recycling site: Contamination pathways and implications for potential mitigation strategies. Environment International. 137:105563. doi:
[22] Zhang J, Wu X, Guo H, Zheng X, Mai B. 2021. Pollution of plastic debris and halogenated flame retardants (HFRs) in soil from an abandoned e-waste recycling site: Do plastics contribute to (HFRs) in soil? Journal of Hazardous Materials. 410:124649.
[23] Bi X, Thomas GO, Jones KC, Qu W, Sheng G, Martin FL, Fu J. 2007. Exposure of electronics dismantling workers to polybrominated diphenyl ethers, polychlorinated biphenyls, and organochlorine pesticides in South China. Environ Sci Technol. 41(16):5647-53.
[24] Liu L, Zhang B, Lin K, Zhang Y, Xu X, Huo X. 2018. Thyroid disruption and reduced mental development in children from an informal e-waste recycling area: a mediation analysis. Chemosphere. 193:498–505.
[25] Cai H, Xu X, Zhang Y, Cong X, Lu X, Huo X. 2019. Elevated lead levels from e-waste exposure are linked to sensory integration difficulties in preschool children. Neurotoxicology. 71:150–58.
[26] Zeng X, Huo X, Xu X, Liu D, Wu W. 2020. E-waste lead exposure and children’s health in China. Science of The Total Environment. 734:139286. doi: 10.1016/j.scitotenv.2020.139.
[27] Zhang Y, O’Connor D, Xu W, Hou D. 2020. Blood lead levels among Chinese children: The shifting influence of industry, traffic, and e-waste over three decades. Environment International. 135:105379. doi: 10.1016/j.envint.2019.105379.
[28] Ngo HTT, Liang L, Nguyen DB, Doan HN, Watchalayann P. 2020. Environmental Pollution of Heavy Metals in a Vietnamese Informal E-waste Processing Village. Applied Environmental Research. 42(1):71-84. doi:
[29] Ngo HTT, Watchalayann P, Nguyen DB, Doan HN, Liang L. 2021. Evaluation of heavy metal exposure pathways on children from an informal e-waste processing village in Vietnam. Human and Ecological Risk Assessment: An International Journal. 27:2342-2358.
[30] Cai K, Song Q, Yuan W, Ruan J, Duan H, Li Y, Li J. 2020. Human exposure to PBDEs in e-waste areas: A review. Environmental Pollution. 267:115634. doi:
[31] Eguchi A, Kunisue T, Wu Q, Trang PTK, Viet PH, Kannan K, Tanabe S. 2014. Occurrence of perchlorate and thiocyanate in human serum from e-waste recycling and reference sites in Vietnam: association with thyroid hormone and iodide levels. Archives of environmental contamination and toxicology. 67:29-41.
[32] Eguchi A, Nomiyama K, Tue NM, Trang PTK, Viet PH, Takahashi S, Tanabe S. 2015. Residue profiles of organohalogen compounds in human serum from e-waste recycling sites in North Vietnam: association with thyroid hormone levels. Environmental research. 137:440-449.
[33] Kincaid, J. 2019. Organohalogen contamination in Vietnamese women electronic waste recyclers living and working in rural northern Vietnam. Prehosp. Disaster Med. 34:155.
[32] Ma Y, Stubbings WA, Cline-Cole R, Harrad S. 2021. Human exposure to halogenated and organophosphate flame retardants through informal e-waste handling activities - A critical review. Environmental Pollution. 268:115727. doi:
[33] Muto M, Ramu K, Isobe T, Tue NM, Viet PH, Takahashi S, Tanabe S. 2012. Contamination of Brominated Flame Retardants (BFRs) in human hair from e-waste recycling site in Vietnam. Interdisciplinary Studies on Environmental Chemistry—Environmental Pollution and Ecotoxicology. 229-237.
[34] Tue NM, Katsura K, Suzuki G, Takasuga T, Takahashi S, Viet PH, Tanabe S. 2014. Dioxin-related compounds in breast milk of women from Vietnamese e-waste recycling sites: Levels, toxic equivalents and relevance of non-dietary exposure. Ecotoxicology and environmental safety. 106:220-225. doi:
[35] Tue NM, Sudaryanto A, Minh TB, Isobe T, Takahashi S, Viet PH, Tanabe S. 2010. Accumulation of polychlorinated biphenyls and brominated flame retardants in breast milk from women living in Vietnamese e-waste recycling sites. Science of the Total Environment. 408(9):2155-2162. doi:
[36] Simmons K. 2019. Operating procedure: soil sampling. Washington, DC: US Environmental Protection Agency. 24. Available from:
[37] United States Environmental Protection Agency (USEPA). Method 3051A. (2007). Microwave-assisted acid digestion of sediments, sludges, soils, and oils. Revision 1. Washington, DC:
[38] Pal, S. K., Sharma, A., & Kumari, V. (2021). Reverse aqua regia: a new method for extraction of diatoms from human tissue. Int J Forensic Sci Pathol. 8(01):425-429.
[39] Stanton RE. 1966. Rapid methods of trace analysis for geochemical applications. London: Edward Arnold Ltd.
[40] Valcarcel M. 2000. Principles of analytical Chemistry. New York: Springer-Verlag Berlin Heidelberg.
[41] Jiang X, Lu WX, Zhao HQ, Yang QC, Yang ZP. 2014. Potential ecological risk assessment and prediction of soil heavy-metal pollution around coal gangue dump. Natural Hazards and Earth System Sciences. 14(6):1599-1610.
[42] Thomlinson DL, Wilson JG, Harris CR, Jeffrey DW. 1980. Problems in the assessment of heavy-metal levels in estuaries and the formation of a pollution index. HelgolanderMeeresunters. 33:566–575. Available from:
[43] Wu Q, Leung JYS, Geng X, Chen S, Huang X, Li H, Huang Z, Zhu L, Chen J, Lu Y. 2015. Heavy metal contamination of soil and water in the vicinity of an abandoned e-waste recycling site: Implications for dissemination of heavy metals. Science of The Total Environment. 506(507):217-225.
[44] Qingjie G, Jun D, Yunchuan X. 2008. Calculating Pollution Indices by Heavy Metals in Ecological Geochemistry Assessment and a Case Study in Parks of Beijing. Journal of China University of Geosciences. 19:230–241.
[45] Sun Y, Zhou Q, Xie X, Liu R. 2010. Spatial, sources and risk assessment of heavy metal contamination of urban soils in typical regions of Shenyang, China. Journal of Hazardous Materials. 174:455–462.
[46] Amuno SA. 2013. Potential Ecological Risk of Heavy Metal Distribution in Cemetery Soils. Water Air Soil Pollution. 224:1–12.
[47] Hakanson L. 1980. An ecological risk index for aquatic pollution control: A sedimentological approach. Water Research, 14(8): 975-1001. doi:10.1016/0043-1354(80)90143-8
[48] Men C, Liu R, Xu F, Wang Q, Guo L, Shen Z. 2018. Pollution characteristics, risk assessment, and source apportionment of heavy metals in road dust in Beijing. China. Sci. Total Environ. 612:138–147. Doi: 10.1016/j.scitotenv.2017.08.123.
[49] Slavković L, Škrbić B, Miljević N, Onjia A. 2004. Principal component analysis of trace elements in industrial soils. Environmental Chemistry Letters. 2:105-108. doi:10.1007/s10311-004-007378.
[50] Zhang J, Zhou F, Chen C, Sun X, Shi Y, Zhao H, Chen F. 2018. Spatial distribution and correlation characteristics of heavy metals in the seawater, suspended particulate matter and sediments in Zhanjiang Bay, China. PLoS One. 13(8):e0201414.
[51] Egbueri JC, Ukah BU, Ubido OE, Unigwe CO. 2020. A chemometric approach to source apportionment, ecological and health risk assessment of heavy metals in industrial soils from southwestern Nigeria. Int. J. Environ. Anal. Chem. 98:1–19. Doi: 10.1080/03067319.2020.1769615
[52] Xu S, Cui Y, Yang C, Wei S, Dong W, Huang L, Liu C, Ren Z, Wang W. 2021. The fuzzy comprehensive evaluation (FCE) and the principal component analysis (PCA) model simulation and its applications in water quality assessment of Nansi Lake Basin, China. Environmental Engineering Research. 26(2):200022.
[53] World Health Organization (WHO). 1996. Linkage methods for environment and health analysis: general guidelines: a report of the Health and Environment Analysis for Decision-making (HEADLAMP) project (No. WHO/EHG/95.26). World Health Organization.
[54] Department of Petroleum Resources (DPR). 2002. Environmental guidelines and standards for the petroleum industry in Nigeria (revised ed.). Nigeria: Ministry of Petroleum and Natural Resources, Department of Petroleum Resources.
[55] Opaluwa OD, Aremu MO, Ogbo LO, Abiola KA, Odiba IE, Abubakar MM, Nweze NO. 2012. Heavy metal concentrations in soils, plant leaves and crops grown around dump sites in Lafia Metropolis, Nasarawa State, Nigeria. Advances in Applied Science Research, 3(2):780-784.
[56] Adesokan MD, Adie GU, Osibanjo O. 2016. Soil Pollution by Toxic Metals near E-waste Recycling Operations in Ibadan, Nigeria. Journal of health & pollution. 6(11):26–33.
[57] Adeyi AA, Oyeleke P. 2017. Heavy Metals and Polycyclic Aromatic Hydrocarbons in Soil from E-waste Dumpsites in Lagos and Ibadan, Nigeria. Journal of health & pollution. 7(15):71–84.
[58] Han W, Gao G, Geng J, Li, Y, Wang Y. 2018. Ecological and health risks assessment and spatial distribution of residual heavy metals in the soil of an e-waste circular economy park in Tianjin, China. Chemosphere. 197:325-335.
[59] Han Y, Tang Z, Sun J, Xing X, Zhang M, Cheng J. 2019. Heavy metals in soil contaminated through e-waste processing activities in a recycling area: Implications for risk management. Process Safety and Environmental Protection. 125:189–196. doi:
[60] Li J, Duan H, Shi P. 2011. Heavy metal contamination of surface soil in electronic waste dismantling area: site investigation and source-apportionment analysis. Waste Management & Research. 29(7):727-738. doi:10.1177/0734242X10397580
[61] Quan SX, Yan B, Yang F, Li N, Xiao XM, Fu JM. 2015. Spatial distribution of heavy metal contamination in soils near a primitive e-waste recycling site. Environmental Science and Pollution Research. 22:1290-1298.
[62] Zhao W, Ding L, Gu X, Luo J, Liu Y, Guo L, Shi Y, Huang T, Cheng S. 2015. Levels and ecological risk assessment of metals in soils from a typical e-waste recycling region in southeast China. Ecotoxicology. 24:1947-1960.
[63] Damrongsiri S, Vassanadumrongdee S, Tanwattana P. 2016. Heavy metal contamination characteristic of soil in WEEE (waste electrical and electronic equipment) dismantling community: a case study of Bangkok, Thailand. Environmental Science and Pollution Research. 23(17):17026-17034.
[64] Pradhan JK, Kumar S. 2014. Informal e-waste recycling: environmental risk assessment of heavy metal contamination in Mandoli industrial area, Delhi, India. Environmental Science and Pollution Research. 21(13):7913-7928. doi:10.1007/s11356-014-2713-2
[65] Oguri T, Suzuki G, Matsukami H, Uchida N, Tue NM, Tuyen LH, Viet PH, Takahashi S, Tanabe S, Takigami H. 2018. Exposure assessment of heavy metals in an e-waste processing area in northern Vietnam. Science of The Total Environment. 621:1115-1123.
[66] Uchida N, Matsukami H, Someya M, Tue NM, Tuyen LH, Viet PH, Takahashi S, Tanabe S, Suzuki G. 2018. Hazardous metals emissions from e-waste-processing sites in a village in northern Vietnam. Emerging Contaminants. 4(1):11-21.
[67] Wu Y, Li Y, Kang D, Wang J, Zhang Y, Du D, Dong Q, Pan B, Lin Z, Huang C, Dong Q. (2016). Tetrabromobisphenol A and heavy metal exposure via dust ingestion in an e-waste recycling region in Southeast China. Science of the Total Environment. 541:356-364. doi:10.1016/j.scitotenv.2015.09.038.
[68] Zeng X, Li J, Stevels ALN, Liu L. 2013. Perspective of electronic waste management in China based on a legislation comparison between China and the EU. Journal of Cleaner Production. 51:80-87. doi:
[69] Shen CF, Chen YX, Huang SB, Wang ZJ, Yu CN, Qiao M, Xu M, Setty K, Zhang JY, Lin Q, 2009. Dioxin-like compounds in agricultural soils near e-waste recycling sites from Taizhou area, China: Chemical and Bioanalytical Characterization. Environ. Int. 35:50e55.
[70] Zheng J, Chen K, Yan X, Chen S, Hu G, Peng X, Yuan J, Mai B, Yang Z. 2013. Heavy metals in food, house dust, and water from an e-waste recycling area in South China and the potential risk to human health. Ecotoxicology and Environmental Safety. 96:205-212. doi:
[71] Cao S, Duan X, Zhao X, Ma J, Dong T, Huang N, Wei F. 2014. Health risks from the exposure of children to As, Se, Pb and other heavy metals near the largest coking plant in China. Science of the total environment. 472:1001-1009. doi:
[72] Cao S, Duan X, Zhao X, Wang B, Ma J, Fan D, Jiang G. 2015. Health risk assessment of various metal (loid) s via multiple exposure pathways on children living near a typical lead-acid battery plant, China. Environmental Pollution. 200:16-23.doi:
[73] Hakanson L. 1980. An ecological risk index for aquatic pollution control. A sedimentological approach. Water research. 14(8):975-1001.
[74] Ihedioha JN, Ukoha PO Ekere NR. 2016. Ecological and human health risk assessment of heavy metal contamination in soil of a municipal solid waste dumping Uyo, Nigeria. Environ Geochem Health. 39:497-515. DOI 10.1007/s10653-016-9830-4
[75] Kyere VN, Greve K, Atiemo SM Ephraim J. 2017. Spatial assessment of potential ecological risk of heavy metals in soils from informal e-waste recycling in Ghana. Environmental health and toxicology. 32:2017018.
[76] Isimekhai KA, Garelick H, Watt J, Purchase D. 2017. Heavy metals distribution and risk assessment in soil from an informal e-waste recycling site in Lagos State, Nigeria. Environmental Science and Pollution Research. 24:17206–17219.
[77] Song J, Yang X, Zhang J, Long Y, Zhang Y, Zhang T. 2015. Assessing the variability of heavy metal concentrations in liquid-solid two-phase and related environmental risks in the Weihe River of Shaanxi Province, China. Int J Environ Res Public Health 12:8243–8262.
[78] Hassan MS, Patwary MKK, Rahman MM, Sonia SF, Kabiruzzaman M, Alim MA, Salahuddin AJM, Zahid RI, Ara F, Yusuf NM, Sultana S, Haque A. 2013. Neurological Effect of Lead Exposure in Children. Medicine Today. 25(1):1–5. doi:10.3329/medtoday.v25i1.15899
How to Cite
Bankole, A., Ogunkeyede, A., Ngo, H., Liang, L., Agboro, H., Isimekhai, K., Fadairo, E., Isangadighi, G., Isukuru, E., & Ogbodhu, C. (2024). Ecological Risks of Heavy Metals Found in Soils at Informal E-Waste Processing Sites in Nigeria. European Journal of Science, Innovation and Technology, 4(2), 417-434. Retrieved from