Tobias I Ndubuisi Ezejiofor obtained a BSc degree in Medical Laboratory Sciences (Rivers State University of Science & Technology, Port Harcourt), MSc Applied Biochemistry (Nnamdi Azikiwe University, Awka), and PhD Environmental Health Biology (Federal University of Technology, Owerri(FUTO), Nigeria. He is licensed by Environmental Health Officers Registration and Medical Laboratory Science Councils of Nigeria. A member of many professional associations and learned societies, he is a Fellow of the College of Biomedical Engineering and Technology (FCBET), Nigeria. He is a senior Lecturer and heads the Occupational and Environmental Toxicology Research laboratory of the Department of Biotechnology, FUTO, Nigeria. He has published over 25 papers in reputed journals, and serving as reviewer to many such international journals. He had given several conference papers locally and internationally.


Exposures in chemically hostile environments often result in generation of oxidative stress within the body, on account of excessive production of free radicals. The success of the body in dousing the cascade of ill-events associated with the presence of free radicals depends on the availability of equally potent agents that provide counteractive effects to the activities of free radicals. These agents also known as antioxidants give protection to the body by successfully mopping up excess free radicals in the body. Excess of the radicals over that of the body’s antioxidants reserve, as may happen following exposure to toxic organic pollutants in an industrial environment, often favours the establishment of sundry health effects. This study was designed to examine the status of oxidative stress parameters as possible markers of exposure to toxic organic pollutants among petroleum distribution industry workers in Nigeria. Blood sample (5ml) was collected from each of the 50 study participants consisting of 35 oil workers (exposed), and 15 non oil workers (referents). Standard assay methods were adopted for analyses of the parameters of interest. Result of the study showed that for oil workers, Malondialdehyde(MDA),37.9-96.70(59.31±11.90 mg/dl), Vitamin C, 0.35-1.52 (0.78±0.28 mg/dl),Vitamin E, 0.22-0.51(0.31±0.06mg/dl), Reduced glutathione (GSH) ranged 0.2-0.8 with a mean of 0.49±0.20mg/dl; while among the non-oil workers the values were as follows: MDA, 30.3-60.7(49.58±8.12 mg/dl), Vitamin C, 0.41-2.22 (1.26±0.42 mg/dl), Vitamin E, 0.24-1.99(0.44±0.43 mg/dl), GSH, 0.4-1.7 (mean= 0.83±0.32 mg/dl) respectively. A review of the results show that, among the oil workers, the lipid peroxidation substance, MDA was significantly higher (P=0.006) while the antioxidant parameters were significantly lower (p<0.0001), whereas the reverse was the case among the non-oil workers, because MDA was significantly lower in them (P<0.001) even as most of the antioxidant parameters were significantly higher in them. Higher lipid peroxidation substance (MDA) and a dwindling antioxidants status as found among the oil workers gives a clear signal of a higher presence of free radicals that is depleting the antioxidants reserves in the oil workers as compared with the reverse situation among their non-oil work referents, indicating that relative to the referents, the oil workers were most likely to be affected by adverse conditions associated with oxidative stress including a greater tendency to sundry health effects. The results also showed that oxidative stress markers can indeed serve as putative markers of exposure to toxic organic pollutants in the oil and gas industry.