Toxicological Evaluation Of Two Nigerian Refinery Effluents Using Natural Biomonitors

Abstract

Abstract

The present study aimed to evaluate the toxic effects of two Nigerian refineries’ effluents using natural bio-monitors. Standard physicochemical analysis, toxi-chromo test using mutant E. coli and sub-chronic animal toxicity testing with emphasis on tissue heavy metal accumulation, biochemical parameters and histopathology, were adopted during the study. The physicochemical results revealed that the two effluent samples are highly polluted although PH sample was more polluted than the Warri sample. Toxi-chromo testing revealed that the positive control sample (HgCl2) exhibited the most harmful effect on 50% population of mutant E. coli with EC50 value of 1.535 mg/L. The mice model revealed that iron (1.616 mg/kg) and lead (0.169 mg/kg) had the highest accumulation in the Warri exposed liver tissues of the mice. PH sample had the highest values of the biomarkers but statistical analysis showed a significant difference (p<0.05) between the samples and control with R2 value of 0.304. There were non-cancerous changes in the architectural structure and integrity of the observed liver and kidney tissues in comparison to their controls with normal architecture. Hence, adequate and strict measures should be established by government and environmental policymakers to ensure proper treatment and monitoring of these liquid wastes before they are discharged into our terrestrial and aquatic environments.

Keywords: Animal model, E. coli, environmental health, pollution, refinery effluents

Cite this Article

Samson Ogagaoghene Egurefa, Micheal Uchenna Orji and Bright Obidinma Uba. Toxicological Evaluation of Two Nigerian Refinery Effluents using Natural Biomonitors. Research & Reviews: A Journal of Toxicology. 2020; 10(2): 22–31p.