Analysis of Fish Samples for Heavy Metals And Total Hydrocarbon Content From Okrika And Bonny Rivers In Rivers State, Nigeria
Keywords:
Fish, Heavy Metal, Total Hydrocarbon, Okrika and Bonny, Rivers StateAbstract
This study examines the concentrations of heavy metals (cadmium [Cd), chromium [Cr), lead (Pb), arsenic (As), and nickel (Ni) and total hydrocarbon content (THC) in three fish species (Illish, Mullet, and Tilapia) from Okrika and Bonny Rivers in Rivers State, Nigeria. Fresh fish samples were collected and analyzed to assess their contamination levels. Heavy metals were determined using Atomic Absorption Spectrophotometry (AAS), while THC was analyzed using standard extraction techniques and Gas Chromatography-Mass Spectrometry (GC-MS). The results revealed that the concentrations of heavy metals in fish species exceeded permissible limits set by the Food and Agriculture Organization (FAO) and World Health Organization (WHO) in several instances. Notably, Mullet Fish from Okrika River exhibited significantly elevated levels of Cd (2.0±0.36 mg/kg), Cr (2.02±0.12 mg/kg), Pb (10.25±1.03 mg/kg), and As (2.5±0.37 mg/kg). Similarly, fish from Bonny River also displayed high levels of contaminants, albeit generally lower than those from Okrika River. The THC levels, while below the Department of Petroleum Resources (DPR) threshold of 50 mg/kg, reflected ongoing hydrocarbon pollution, with Mullet Fish from Okrika River recording 3.08±0.06 mg/kg. Comparative analysis with existing literature highlights the severe pollution levels in these rivers, likely driven by industrial discharges, urban runoff, and oil-related activities. Species-specific trends indicate higher contaminant bioaccumulation in Mullet Fish, attributed to their benthic feeding habits. The study underscores significant environmental and public health concerns, given the reliance of local communities on these rivers for fish consumption. Urgent interventions, including stricter pollution control, sustainable waste management, and regular monitoring, are recommended to mitigate the risks posed by heavy metal and hydrocarbon contamination in aquatic ecosystems.
References
Alloway, B. J. (2013). Heavy metals in soils: Trace metals and metalloids in soils and their bioavailability (3rd ed.). Springer
Adebisi, N. O., Adeyemi, O. O., Kalumba, D., Chebet, F. C., & Osinowo, V. O. (2021). Corrosion potential and geotechnical properties of subsoils from offshore Niger Delta, southern Nigeria. Arabian Journal of Geosciences, 14(14), 1–18.
Asuquo, F. E., Ewa-Oboho, I., Asuquo, E. F., & Udo, P. J. (2004). Fish species used as biomarkers for heavy metal and hydrocarbon contamination for Cross River, Nigeria. Environmentalist, 24(1), 29–37.
Avenant-Oldewage, A., & Marx, H. M. (2000). Bioaccumulation of chromium, copper and iron in the organs and tissues of Clarias gariepinus in the Olifants River, Kruger National Park. Water SA, 26(4), 569–582.
Chikodiri, E., Adondua, M. A., Olawale, O., Yohann, R., & Han, Z. S. (2022). Ecological risk assessment of heavy metals in fish samples from Donga River, Taraba State, Nigeria. Asian Journal of Applied Sciences, 15(1), 24–28.
Edokpayi, J. N., Odiyo, J. O., Popoola, E. O., & Msagati, T. A. M. (2017). Evaluation of temporary seasonal variation of heavy metals and their potential ecological risk in Nzhelele River, South Africa. Open Chemistry, 15(1), 272–282
Eneji, I. S., Sha’Ato, R., & Annune, P. A. (2012). An assessment of heavy metals loading in River Benue in the Makurdi Metropolitan Area in Central Nigeria. Environmental Monitoring and Assessment, 184(1), 201–207.
Inengite, A. K., Oforka, N. C., & Osuji, L. C. (2010). Evaluation of polycyclic aromatic hydrocarbons in sediment of Kolo Creek in the Niger Delta. International Journal of Applied Environmental Sciences, 5(1), 127–134.
Izadiyar, M. H., & Yargholi, B. (2010). Study of cadmium absorption and accumulation in different parts of four forages. Journal of Agriculture and Environmental Sciences, 9(3), 53–62.
Ndimele, P. E., Saba, A. O., Ojo, D. O., Ndimele, C. C., Anetekhai, M. A., & Erondu, E. S. (2018). Remediation of crude oil spillage. In The political ecology of oil and gas activities in the Nigerian aquatic ecosystem (379–397). Academic Press.
Osuagwu, E. S., & Olaifa, E. (2018). Effects of oil spills on fish production in the Niger Delta. PLoS ONE, 13(10), 1–12.
Verma, R., & Dwivedi, P. (2013). Heavy metal water pollution: A case study. Science and Technology, 5(5), 98–99.
