The concentration and health risk assessment of heavy metals and microorganisms in the groundwater of Lagos, Southwest Nigeria

Document Type : Original Article


1 Department of Biology, Federal University Birnin Kebbi, P.M.B 1157, Birnin Kebbi, Nigeria

2 Biology Unit, Distance Learning Institute, University of Lagos, Nigeria

3 Department of Environmental Science and Toxicology, National Open University of Nigeria, Lagos


Contaminated water is increasingly linked to diseases worldwide, necessitating the safety evaluation of the sources of domestic and drinking water in every locality. The present study aimed to assess water safety in terms of lead (Pb), nickel (Ni), cadmium (Cd), copper (Cu), chromium (Cr), zinc (Zn), and microorganisms in the borehole and well water in Iwaya, Makoko, and Ilaje in Lagos, Nigeria. Water samples were subjected to atomic absorption spectroscopy (AAS) and microbiological examinations using standard protocols and compared with the World Health Organization (WHO) permissible limits. The average daily ingestion (ADI) and hazard quotient (HQ) of the selected heavy metals were also calculated using standard formulas. The AAS indicated that the borehole and well water of the three locations contained non-permissible levels of Pb, Ni, and Cd (only the well water in Ilaje), while Zn, Cu, and Cr were normal. In addition, the microbiological examinations showed that the borehole and well water of the three locations contained abnormal bacteria and coliform counts (well water only). The ADI and HQ of the selected heavy metals were less than one, which is the threshold at which a substance is considered safe for consumption. Water could pose some health risks, and the consumers in high-risk areas should consider water treatment before consumption.


1. Center for Disease Control. Global WASH Health Burden. 2017. Available at:
2. Landrigan PJ, Fuller R, Acosta NJR, Adeyi O, Arnold R, Basu N, et al. The Lancet Commission on pollution and health. Lancet Comm 2017; 391 (10119) (2018): 462-512.
3. World Health Organization. Diarrheal disease. 2017. Available at:
4. Järup L. Hazards of heavy metal contamination. Br Med Bull 2003; 68: 167-82.
5. Rehman K, Fatima F, Waheed I, Akash MSH. Prevalence of exposure of heavy metals and their impact on health consequences. J Cell Biochem 2018; 119(1): 157-84.
6. Morais S, Costa FG, Pereira ML. Heavy metals and human health. Environmental Health- Emerging Issues and Practice, Jacques Oosthuizen (Ed), IntechOpen, Chapter 10, pp 2-23. 2012.
7. Ashbolt NJ. Microbial contamination of drinking water and human health from community water systems. Curr Environ Health Rep 2015; 2(1): 95–106.
8. World Health Organization. Guidelines for Drinking-Water Quality: Fourth Edition Incorporating the First Addendum. World Health Organization, Geneva, Switzerland, 2017. Available at:
9. Alberts B, Johnson A, Lewis J, Raff M, Roberts K, Walter P. Molecular Biology of the Cell. 4th edition. New York: Garland Science; 2002. Cell Biology of Infection. Available at:
10. Da Silva GJ, Domingues S. We Are Never Alone: Living with the Human Microbiota. Front Young Minds 2017; 5: 35.
11. Engwa GA, Ferdinand PU, Nwalo FN, Unachukwu MN. Mechanism and health effects of heavy metal toxicity in humans. Poisoning in the Modern World - New Tricks for an Old Dog?, Ozgur Karcioglu and Banu Arslan, IntechOpen, 2019.
12. Afolabi TA, Ogbuneke CC, Ogunkunle OA, Bamiro FO. Comparative assessment of the potable quality of water from industrial, urban and rural parts of Lagos, Nigeria. Ife J Sci 2012; 14(2): 221-32.
13. Popoola LT, Yusuff AS, Aderibigbe TA. Assessment of natural groundwater physico-chemical properties in major industrial and residential locations of Lagos metropolis. Appl Water Sci 2019; 9: 191.
14. Wang J, Maduako IN. Spatio-temporal urban growth dynamics of Lagos Metropolitan Region of Nigeria based on Hybrid methods for LULC modeling and prediction. Eur J Remote Sens 2018; 51(1): 251-65.
15. Obia AE. Emerging Nigerian Megacities and Sustainable Development: Case Study of Lagos and Abuja. J Sustain Dev 2016; 9(2): 27-42.
16. Yahaya T, Doherty VF, Akinola OS, Shamsudeen A. Heavy metal profile and microbial counts of selected sachet water brands in Birnin Kebbi. Ife J Sci 2019; 21(1): 229-34.
17. Brock TD. Membrane Filtration. A User's Guide and Reference Manual. XII + 381. J Basic Microbiol 1984; 24(4): 236-8.
18. Yahaya T, Oladele E, Sifau M, Audu M, Bala J, Shamsudeen A. Characterization and cytogenotoxicity of Birnin Kebbi Central Abattoir wastewater. Uniport J Eng Sci Res 2020; 5(special issue): 63-70.
19. United States Environmental Protection Agency. Exposure factors handbook: 2011 edition. Washington, D.C, p1436.
20. Adesiyan IM, Bisi-Johnson M, Aladesanmi OT, Okoh AI, Ogunfowokan AO. Concentrations and human health risk of heavy metals in rivers in southwest Nigeria. J Health Pollut 2018; 8(19): 180907.
21. Yahaya TO, Ogundipe OA, Abdulazeez A, Usman B, Danjuma J. Bioaccumulation and health risk assessment of heavy metals in three vegetables consumed in Lagos, south-west Nigeria. Trop J Nat Prod Res 2019; 3(11): 332-8.
22. Ehi-Eromosele CO, Okiei WO. Heavy metal assessment of ground, surface and tap water samples in Lagos metropolis using anodic stripping voltammetry. Resour Environ 2012; 2(3): 82-6.
23. Chika OC, Prince EA. Comparative assessment of trace and heavy metals in available drinking water from different sources in the Centre of Lagos and off Town (Ikorodu LGA) of Lagos State, Nigeria. Adv J Chem A 2020; 3(1): 94-104.
24. Adelekan BA, Ogunde OA. Quality of water from dug wells and the lagoon in Lagos Nigeria and associated health risks. Sci Res Essays 2012; 7(11): 1195-211.
25. Genchi G, Carocci A, Lauria G, Sinicropi MS, Catalano A. Nickel: Human health and environmental toxicology. Int J Environ Res Public Health 2020; 17(3): 679.
26. Sun H, Brocato J, Costa M. Oral chromium exposure and toxicity. Curr Environ Health Rep 2015; 2(3): 295–303.
27. Taylor AA, Tsuji JS, Garry MR, McArdle ME, Goodfellow Jr. WL, Adams WJ, et al. Critical review of exposure and effects: Implications for setting regulatory health criteria for ingested copper. Environ Manage 2020; 65: 131–59.
28. Plum LM, Rink L, Haase H. The essential toxin: Impact of zinc on human health. Int J Environ Res Public Health 2010; 7(4): 1342–65.
29. World Health Organization. International year of freshwater. General assembly resolution A/RES/55/196. World Health Organization, Geneva, 2003. Available at: (Accessed on August 18, 2020).
30. Adeniyi A, Yusuf K, Okedeyi O, Sowemimo M. Classification and health risk assessment for borehole water contaminated by metals in selected households in Southwest Nigeria. J Water Resour Prot 2016; 8(4): 459-71.
31. Ukah B, Egbueri JC, Unigwe C,  Ubido OE. Extent of heavy metals pollution and health risk assessment of groundwater in a densely populated industrial area, Lagos, Nigeria. Int J Energy Water Resour 2019; 3(4): 291–303.
32. Sogbanmu TO, Aitsegame SO, Otubanjo OA, Odiyo JO. Drinking water quality and human health risk evaluations in rural and urban areas of Ibeju-Lekki and Epe local government areas, Lagos, Nigeria. Hum Ecol Risk Assess 2020; 26(4): 1062-75.
33. Atique Ullah AKM, Maksud MA, Khan SR, Lutfa LN, Quraishi SB. Dietary intake of heavy metals from eight highly consumed species of cultured fish and possible human health risk implications in Bangladesh. Toxicol Rep 2017; 4: 574–9.
34. Zhang YJ, Li S, Gan RY, Zhou T, Xu DP, Li HB. Impacts of gut bacteria on human health and diseases. Int J Mol Sci 2015; 16(4): 7493–519.
35. Gruber JS, Ercumen A, Colford JM. Coliform bacteria as indicators of diarrheal risk in household drinking water: Systematic review and meta-analysis. PloS one 2014; 9(9): e107429.
36. Egwari L, Aboaba OO. Environmental impact on the bacteriological quality of domestic water supplies in Lagos, Nigeria. Rev Saúde Pública 2002; 36(4): 513-20.
37. World Health Organization. Guidelines for Drinking water- Quality: Incorporating the first and second addenda volume1: Recommendations. World Health Organization, Geneva, Switzerland. 2008.