Valuation of the toxicity profile of benthic sediment of Western region in sub-Saharan Africa.

Abstract

Sediments in water ecology play an important part in affecting the contamination state since they can perform as both pollutants' carriers and bases in an aquatic ecosystem. The sediment samples of River Okhuaihe were examined to reveal its level of pollution. Sediment samples gotten from 4 stations were analyzed for 28 physical and chemical parameters using the standard methods. A high P < 0.01 (significant difference) was detected in nitrate, electrical conductivity, available phosphorus, zinc, lead, chromium, and total hydrocarbon content, while cadmium, manganese, potassium, total nitrogen, and total organic carbon were P < 0.05 (significantly different) across the studied stations. The Duncan multiple range test showed that station 3 was the source of variance for these parameters. All other parameters showed no P > 0.05 (significant difference) across the studied stations. Temporal examination revealed disparities in the arid and rainy periods, for all studied parameters. The mean heavy metal concentrations in the study dwindled in this order: Fe > Zn > Mn > Cd > Cu > Pb > Cr > Ni > V. The principal component analysis results revealed two components that influenced the sediment characteristic of River Okhuaihe, with eigenvalues > 1 accounting for 96.811% of the sum variance. The pollution load index of stations 1, 2, 3, and 4 was 3.54, 2.60, 4.07, and 4.02, respectively, which were greater than the threshold, showing high contamination. This shows that River Okhuaihe is highly polluted with specific sources of organic wastes from farming activities which in turn influence the pH and metal solubility contents of the water body. Therefore, there is a dire need to do regular monitoring of the discharged wastes into the river by water researchers and regulatory bodies to maintain and enhance its natural integrity against unforeseen health issues for the present and future users.