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Journal of Heavy Metal Research
Quarterly Publication

Assessment of Metal (loid)s in Tap Water from Schools in the Niger Delta: Water Quality and Health Risk Implications for Students

https://doi.org/10.22034/jhmr.2026.561364.1008
Volume 1, Issue 2 - Serial Number 2
Spring 2026
Pages 1-9
Journal of Heavy Metal Research

Document Type : Original Article

Authors

Kelechi Chinedu Akporhona 1
Nneka Chukwumar 2
Fatima Anuoluwapo 2

1 Department of Chemistry, Delta State University, Abraka, Nigeria

2 Environmental Impact Assessment, Environment Department, Shell Petroleum Development Company, Port Harcourt, Nigeria

Abstract
The Niger Delta region of Nigeria faces persistent water quality challenges driven by rapid urbanization, oil-related industrial activity, and aging infrastructure. Despite numerous environmental assessments in the region, drinking water quality within schools—where children represent a highly vulnerable population—remains largely unexplored. This study provides a targeted evaluation of metal(loid) contamination in tap water from 30 primary and secondary schools distributed across urban (Port Harcourt, Warri) and peri-urban/rural communities. Concentrations of Pb, Cd, As, Hg, Cr, Ni, Cu, Zn, Fe, and Mn were determined using atomic absorption spectrometry, with rigorous QA/QC procedures. Samples were collected under flushed conditions and acidified, representing total recoverable metal fractions. Mean concentrations (µg/L) decreased in the order Zn > Fe > Cu > Mn > Pb > Ni > Cr > As > Cd > Hg. Lead exceeded the WHO guideline (10 µg/L) in 47% of schools. Entropy-Weighted Water Quality Index (EWQI) results classified 80% of samples as excellent to good, whereas 20% were medium to poor. Multivariate analyses (PCA with KMO = 0.72; Bartlett’s p < 0.001) identified two dominant factors: (1) infrastructure-related corrosion (Pb–Zn–Cu–Fe) and (2) geogenic/industrial influences (As–Hg–Cr). Health risk assessment following USEPA guidelines indicated that non-carcinogenic risk was generally below the safety threshold (HI < 1), although exceedances occurred in 10% of schools for children. Carcinogenic risk values for Pb and As surpassed the acceptable limit (1 × 10⁻⁴) in 30% of locations. Although limited by sample size and single-season sampling, the findings highlight infrastructure deterioration as a key determinant of school drinking water quality and underscore the need for systematic monitoring and targeted remediation to protect children’s health.

Keywords

Niger Delta
Tap water
Heavy Metals
Health risk assessment
Water quality
Source apportionment
Subjects
Adesuyi, A. A., Nnodu, V. C., Njoku, K. L., & Jolaoso, A. (2015). Nitrate and phosphate pollution in surface water of Nwaja Creek, Port Harcourt, Niger Delta, Nigeria.International Journal of Geology, Agriculture and Environmental Sciences, 3(5), 14–20.
Bello, A., & Amadi, J. (2019). Oil pollution and biodiversity conservation in Nigeria: An assessment of legal framework. Journal of Geoscience and Environment Protection, 7(8), 354-371. https://doi.org/10.4236/gep.2019.78024
Emoyan, O. O., Akpoborie, I. A., & Akporhonor, E. E. (2008). The oil and gas industry and the Niger-Delta: Implications for the environment. Journal of Applied Sciences and Environmental Management, 12(3), 29-37.
Jaishankar, M., Tseten, T., Anbalagan, N., Mathew, B. B., & Beeregowda, K. N. (2014). Toxicity, mechanism and health effects of some heavy metals. Interdisciplinary Toxicology, 7(2), 60–72. https://doi.org/10.2478/intox-2014-0009
Landrigan, P. J., Fuller, R., Acosta, N. J. R., Adeyi, O., Arnold, R., Baldé, A. B., ... & Flahault, A. (2018). The Lancet Commission on pollution and health. The Lancet, 391(10119), 462–512. https://doi.org/10.1016/S0140-6736(17)32345-0
Lanphear, B. P., Hornung, R., Khoury, J., Yolton, K., Baghurst, P., Bellinger, D. C., ... & Roberts, R. (2005). Low-level environmental lead exposure and children's intellectual function: An international pooled analysis. Environmental Health Perspectives, 113(7), 894–899.
Namdari, S., Valizade, K., Rasuly, A., & Chehregosha, N. (2016). Spatio-temporal analysis of MODIS AOD over western part of Iran. Arabian Journal of Geosciences, 9, Article 191. https://doi.org/10.1007/s12517-015-2029-7
Ogundele, L. T., Adejoro, I. A., & Ayeku, P. O. (2019). Health risk assessment of heavy metals in soil samples from an abandoned industrial waste dumpsite in Ibadan, Nigeria. Environmental Monitoring and Assessment, 191(5), Article 290. https://doi.org/10.1007/s10661-019-7454-8
Ordinioha, B., & Brisibe, S. (2013). The human health implications of crude oil spills in the Niger Delta, Nigeria: An interpretation of published studies. Nigerian Medical Journal, 54(1), 10–16. https://doi.org/10.4103/0300-1652.108887
Short, K. C., & Stauble, A. J. (1967). Outline of geology of Niger Delta. AAPG Bulletin, 51(5), 761–779.
Siddique, M. A. B., Khan, R., Islam, A. R. M. T., Al-Amin, H. O., Akbor, M. A., & Rahman, M. M. (2021). Quality assessment of freshwaters from a coastal city of southern Bangladesh: Irrigation feasibility and preliminary health risks appraisal. Environmental Nanotechnology, Monitoring & Management, 16, 100524. https://doi.org/10.1016/j.enmm.2021.100524
Standards Organisation of Nigeria. (2015). Nigerian Standard for Drinking Water Quality (NSDWQ), NIS 554:2015.
Tchounwou, P. B., Yedjou, C. G., Patlolla, A. K., & Sutton, D. J. (2012). Heavy metal toxicity and the environment. In Experientia Supplementum (Vol. 101, pp. 133–164). https://doi.org/10.1007/978-3-7643-8340-4_6
United Nations Development Programme. (2006). Niger Delta Human Development Report.
United States Environmental Protection Agency. (2004). Risk assessment guidance for Superfund volume I: Human health evaluation manual (Part E, supplemental guidance for dermal risk assessment) (EPA/540/R/99/005). Office of Superfund Remediation and Technology Innovation.
United States Environmental Protection Agency. (2009). National primary drinking water regulations (EPA 816-F-09-004). Office of Water.
United States Environmental Protection Agency. (2011). Exposure factors handbook: 2011 edition (EPA/600/R-09/052F).
United States Environmental Protection Agency. (2023). Integrated Risk Information System (IRIS). Retrieved November 21, 2025, from https://www.epa.gov/iris
UN-Water. (2018). Sustainable Development Goal 6 Synthesis Report on Water and Sanitation. United Nations.
World Health Organization. (2006). Principles for evaluating health risks in children associated with exposure to chemicals (Environmental Health Criteria 237).
World Health Organization. (2017). Guidelines for drinking-water quality: Fourth edition incorporating the first addendum.
 
  • Receive Date 22 November 2025
  • Revise Date 26 February 2026
  • Accept Date 22 April 2026
  • Publish Date 01 May 2026

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