ECOLOGICAL ASSESSMENT OF STREAMBED SEDIMENTS AND FRESHWATER FISH SPECIES OF EDE-ONYIMA LAKE, IN OKARKI-ENGENNI, RIVERS STATE, NIGERIA

MCLEAN STANLEY ESSIENE *

Institute of Natural Resources, Environment and Sustainable Development, University of Port Harcourt, Choba, Rivers State, Nigeria.

ADUABOBO IBITORU HART

Institute of Natural Resources, Environment and Sustainable Development, University of Port Harcourt, Choba, Rivers State, Nigeria and Department of Animal and Environmental Biology, University of Port Harcourt, Choba, Rivers State, Nigeria.

LEO CHIGBU OSUJI

Institute of Natural Resources, Environment and Sustainable Development, University of Port Harcourt, Choba, Rivers State, Nigeria, World Bank Africa Centre of Excellence for Oil Field Chemicals Research, Nigeria and Department of Pure and Industrial Chemistry, University of Port Harcourt, Choba, Rivers State, Nigeria.

MUDIAGA CHUKUNEDUM ONOJAKE

World Bank Africa Centre of Excellence for Oil Field Chemicals Research, Nigeria and Department of Pure and Industrial Chemistry, University of Port Harcourt, Choba, Rivers State, Nigeria.

*Author to whom correspondence should be addressed.


Abstract

Aquatic ecosystems are heavily polluted by potentially toxic substances deposited in the sediment as a result of anthropogenic activities. These substances have the potential to enter the food chain, posing significant risks to human health and the environment. Five trace metals such as chromium (Cr), nickel (Ni), cadmium (Cd), lead (Pb) and Polycyclic Aromatic hydrocarbons (PAHs) which are regarded as potentially toxic substances were determined in sediments and soft tissues of three commonly consumed fish species, Ageneiosus ucayalensis, Alestes baremoze, and Clarias gariepinus, collected at six sampling sites in Ede Onyima Creek, Okarki-Engenni, Rivers State, Nigeria. The results of trace metals in sediments showed the following range: Ni (1.25 – 11.90 mg/kg); Pb (0.23 – 20.21 mg/kg), Cd (0.09 – 0.72 mg/kg); Cr (0.25 – 11.96 mg/kg) and PAHs (1.25 – 11.90 mg/kg). The mean whole-body concentration of the analyte in three fish species followed the order: Pb > Ni > Cd > PAHs > Cr. The concentrations of the trace metals in sediment were below the quality guideline values; PAHs, had higher threshold and probable effect concentrations (LEL, TEL-HA28, PEL-HA28), indicating toxicity to benthic organisms. The biota-sediment accumulation factor (BSAF) for the fish species ranked in the following order Cd>Pb> Ni>PAHs> Cr. Trace metal concentrations in the fish species exceeded the international permissible limits, indicating that these species are not suitable for human consumption. The contamination level of analytes was determined using the metal pollution index (MPI), which revealed gross contamination of fish species by Cd and Pb in the order Clarias gariepinus (1.8) > Ageneiosus ucayalensis (1.5) > Alestes baremoze (1.4). Furthermore, the flood event had a significant effect on the sedimentary compartment, remobilizing PTSs availability for fish ingestion while washing away legacy contaminated streambed deposits during baseflow.

Keywords: Pollution index, sediment quality, potentially toxic substances, engenni, bioaccumulation


How to Cite

ESSIENE, M. S., HART, A. I., OSUJI, L. C., & ONOJAKE, M. C. (2022). ECOLOGICAL ASSESSMENT OF STREAMBED SEDIMENTS AND FRESHWATER FISH SPECIES OF EDE-ONYIMA LAKE, IN OKARKI-ENGENNI, RIVERS STATE, NIGERIA. Journal of Basic and Applied Research International, 28(5), 1–15. https://doi.org/10.56557/jobari/2022/v28i57881