Assessment of Pollution Load And Its Ecological and Societal Impacts Along the Ona River, Ibadan, Nigeria

Abstract: This study investigates the impact of pollution load on the aquatic ecosystem of the Ona River in southwestern Nigeria, as well as the associated risks to the surrounding riverine communities. The Ona River, a vital freshwater resource traversing densely populated and industrialised zones, receives diverse effluents from industrial, agricultural, and domestic activities. A stratified sampling strategy was employed across nine sites, with water samples analysed for physicochemical and microbiological parameters, including heavy metals. The Pollution Load Index (PLI) was used to quantify the levels of contamination. Results revealed significant concentrations of heavy metals, notably lead (0.008–0.028 mg/L), iron (0.115–0.396 mg/L), arsenic (0.04 ± 0.02 mg/L), and chromium (0.06 ± 0.03 mg/L), several of which exceeded World Health Organisation (WHO) permissible limits. These contaminants pose substantial ecological risks by threatening aquatic biodiversity and disrupting ecosystem services, while also presenting severe public health concerns such as neurotoxicity, carcinogenesis, and organ dysfunction. Statistical analysis indicated uniform distribution of pollutants across sites, suggesting persistent pollution sources. The findings underscore the urgent need for regular monitoring, stringent pollution control, and targeted remediation strategies, including phytoremediation and the use of constructed wetlands. This research contributes to sustainable river management by providing empirical evidence to inform policy interventions that safeguard both ecological integrity and human health.

Phytoremediation, Carcinogenesis, Neurotoxicity, Biodiversity, Remediation

1. Ahmad, W., Alharthy, R. D., Zubair, M., Ahmed, M., Hameed, A., & Rafique, S. (2021). Toxic and heavy metals contamination assessment in soil and water to evaluate human health risk. Scientific reports, 11(1), 17006. [Google Scholar] [Crossref]

2. Akande, A. A. (2025). Assessment Of the Seasonal and Temporal Trends of Physicochemical Parameters and Nutrients of Ona River, Ibadan, Oyo State, Nigeria. Renewable natural resources management and use: a path to sustainable development. [Google Scholar] [Crossref]

3. Ali, S., Naseer, S., Rehman, M., & Wei, Z. (2024). Recent trends and sources of lead toxicity: a review of state-of-the-art nano-remediation strategies. Journal of Nanoparticle Research, 26(7), 168. [Google Scholar] [Crossref]

4. Bhat, A., Ravi, K., Tian, F., & Singh, B. (2024). Arsenic contamination needs serious attention: an opinion and global scenario. Pollutants, 4(2), 196-211. [Google Scholar] [Crossref]

5. Bulbul Ali, A., & Mishra, A. (2022). Effects of dissolved oxygen concentration on freshwater fish: A review. International Journal of Fisheries and Aquatic Studies, 10(4), 113-127. [Google Scholar] [Crossref]

6. Fayiga, A. O., Ipinmoroti, M. O., & Chirenje, T. (2018). Environmental pollution in Africa. Environment, development and sustainability, 20(1), 41-73. [Google Scholar] [Crossref]

7. Ganiyu, S. A., Mabunmi, A. A., Olurin, O. T., Adeyemi, A. A., Jegede, O. A., & Okeh, A. (2021). Assessment of microbial and heavy metal contamination in shallow hand-dug wells bordering Ona River, Southwest Nigeria. Environmental Monitoring and Assessment, 193(3), 126. [Google Scholar] [Crossref]

8. Giri, S. (2021). Water quality prospective in Twenty First Century: Status of water quality in major river basins, contemporary strategies and impediments: A review. Environmental Pollution, 271, 116332. [Google Scholar] [Crossref]

9. Koki, I. B., Bayero, A. S., Umar, A., & Yusuf, S. (2015). Health risk assessment of heavy metals in water, air, soil and fish. African journal of pure and applied chemistry, 9(11), 204-210. [Google Scholar] [Crossref]

10. Lanrewaju, A. A., Enitan-Folami, A. M., Sabiu, S., Edokpayi, J. N., & Swalaha, F. M. (2022). Global public health implications of human exposure to viral contaminated water. Frontiers in Microbiology, 13, 981896. [Google Scholar] [Crossref]

11. Lisetskii, F. N., & Buryak, Z. A. (2023). Runoff of water and its quality under the combined impact of agricultural activities and urban development in a small river basin. Water, 15(13), 2443. [Google Scholar] [Crossref]

12. Mokarram, M., Saber, A., & Sheykhi, V. (2020). Effects of heavy metal contamination on river water quality due to release of industrial effluents. Journal of Cleaner Production, 277, 123380. [Google Scholar] [Crossref]

13. Mukherjee, S., Rizvi, S. S., Biswas, G., Paswan, A. K., Vaiphei, S. P., Warsi, T., & Mitran, T. (2023). Aquatic ecosystems under the influence of climate change and anthropogenic activities: potential threats and their mitigation strategies. Hydrogeochemistry of Aquatic Ecosystems, 307–331. [Google Scholar] [Crossref]

14. Obasi, P. N., & Akudinobi, B. B. (2020). Potential health risk and levels of heavy metals in water resources of lead–zinc mining communities of Abakaliki, southeast Nigeria. Applied Water Science, 10(7), 1-23. [Google Scholar] [Crossref]

15. Ogidi, O. I., & Akpan, U. M. (2022). Aquatic biodiversity loss: impacts of pollution and anthropogenic activities and strategies for conservation. In Biodiversity in Africa: potentials, threats and conservation (pp. 421–448). Singapore: Springer Nature Singapore. [Google Scholar] [Crossref]

16. Ojo, O. M. (2018). River water quality assessment: A case study of River Ona, Southwestern, Nigeria. ABUAD Journal of Engineering Research and Development (AJERD), 1(3), 290–294. [Google Scholar] [Crossref]

17. Pasquale, D. M. (2019). Understanding the role of iron in biofilm formation, characterization, and viable but non-culturable state induction and resuscitation in Salmonella spp (Doctoral dissertation, University of British Columbia). [Google Scholar] [Crossref]

18. Schaffner, M., Bader, H. P., & Scheidegger, R. (2009). Modeling the contribution of point sources and non-poinHuang, J. J., & Xiang, W. (2015). Investigation of point source and non-point source pollution for Panjiakou Reservoir in North China by modelling approach. Water Quality Research Journal of Canada, 50(2), 167-181t sources to Thachin River water pollution. Science of the Total Environment, 407(17), 4902-4915. [Google Scholar] [Crossref]

19. Viana, L. F., Crispim, B. D. A., Sposito, J. C. V., Melo, M. P. D., Francisco, L. F. V., Nascimento, V. A. D., & Barufatti, A. (2021). High iron content in river waters: environmental risks for aquatic biota and human health. Revista Ambiente & Água, 16(5), e2751. [Google Scholar] [Crossref]

20. Wanjari, R. N., Hamid, I., Abass, Z., Magloo, A. H., & Ahmad, I. (2024). Ecosystem Services of Aquatic Biodiversity. Food Security, Nutrition and Sustainability Through Aquaculture Technologies, 207. [Google Scholar] [Crossref]

21. World Health Organization (WHO). (2022). Guidelines for drinking-water quality (4th ed., incorporating 1st addendum). WHO Press. [Google Scholar] [Crossref]

22. Yang, D., Yang, Y., & Xia, J. (2021). Hydrological cycle and water resources in a changing world: A review. Geography and Sustainability, 2(2), 115-122. [Google Scholar] [Crossref]

• Decision Tree and Automatic Linear Modeling Approaches to Predict Body Weight in Indigenous Sabi Sheep and Matebele Goat Females of Zimbabwe
• Microcontroller – Based Automatic Railway Crossing Control and Track Obstacle Monitoring System
• Modelling the Role of Absorptive Capacity in Foreign Direct Investment - Economic Growth Nexus: A Focus on South Africa’s Manufacturing Sector
• AI-Powered Wristband for Accurate BAC Monitoring Using Smart Data Fusion
• Climate Change Impacts on Different Regions