Genotoxicity Of Petroleum Refinery Waste Water In Nigeria

Abstract

The genotoxicity of petroleum refinery wastewater was investigated with the Allium test. 10 medium – sized Allium cepa L. bulbs of the pink variety were induced to sprout roots in distilled water and variously assaulted for 48 hours with different concentrations (v/v) of wastewater from the refinery. Serial dilutions of 20%, 40%. 60%, 80% and 100% were used while distilled water served as control. After the assault, roots were harvested from each treatment sample and assayed for genotoxic effects with the acetocarmine squash technique. Results showed that the wastewater induced statistically highly significant (P ≤ 0.001) mitodepressive effects which were dose-dependent, culminating in total mitotic inhibition at 100% v/v concentration. Other aberrations including stickiness of chromosomes, erosion of chromatin, vagrant chromosomes, fragments and anaphase bridges were induced at higher concentrations (60%-80%) of wastewater. Lower concentrations (20%-40%) induced c-mitosis as the major aberration. The advantages of genotoxicity screening over general toxicity testing in environmental monitoring was highlighted.

Key Words: Allium test, pollution, genotoxicity, chromosome, wastewater.

Global Journal of Environmental Sciences Vol.3(1&2) 2004: 55-58