Dr Osikemekha Anani Anthony and Daniel Ikudayisi Olorunfemi, John Ovie Olomukoro   (Published 2015)

Dr Anani Anthony
See Profile Page


The effect of toxic substances on aquatic lives from a wastewater indiscriminately discharged into the environment during oil and gas exploration activities in Nigeria is the focus of this study. A plant bioassay, the Allium cepa test, was used for the cytogenotoxicity screening of process water on root growth inhibition and chromosome abnormalities in the meristematic roots of the plant. Results of the physicochemical analysis of the wastewater collected from Nigerian Agip Oil Company (NAOC) facility at Ogboinbiri in Bayelsa State at the point of discharge into
the environment showed that it had an unpleasant odour, was slightly alkaline (pH 7.72) and had high electrical conductivity (2793.33 ?S/cm). Lead, manganese, iron, chromium and nickel were present at amounts (0.13, 0.33, 4.47, 0.17 and 0.10 mg/l respectively) above national (NESREA) and international (USEPA) limits for effluent
discharge. Macroscopic evaluation of A. cepa cultivated in the wastewater resulted in significant (p<0.05) concentration-dependent root growth inhibition with an EC
50 value of 14.8 % at 96 h. Root tip cells of the onion bulbs processed for cytological studies by the aceto-orcein squash technique after exposure to the wastewater for 48 h at concentrations of 0.5, 1.0, 2.5, 5.0, and 10% (v/v; wastewater/tap water) showed chromosomal aberrations at all concentrations. Statistical analysis of microscopic results show significant (p<0.05) concentration-dependent frequency of aberrant chromosomes and reduction of mitotic index. The findings in this study calls for proper treatment of process water before its discharge into water bodies to avoid cyto-genetic damages to aquatic lives.

Item Type: Journal article(non-copyrighted)
Format: PDF document,   364.93 KB
Copyright: Creative Commons LicenseCreative Commons license
Keywords: Toxicity, chromosome aberration, Allium cepa, process water
Department: Natural Science
Field of Study: Biology
Uploaded By: Enoyoze Esosa
Date Added: 08 Feb 2019 7:11am
Last Modified: 08 Feb 2019
Journal URL:

Google Docs     Print     Download