Petroleum Hydrocarbon-induced Changes in Juice of Citrus sinensis following Chronic Exposure.

Aim: The aim of this study was to investigate the effect of chronic exposure to petroleum hydrocarbon pollution (PHC) on some biochemical parameters of the fruit juice of Citrus sinensis. Place and Duration of study: This study was carried out at Ebocha-Egbema and Uvuru Mbaise in Imo state (Niger Delta Area), Nigeria between October 2008 and October 2011. Methodology: Acidity (pH), concentrations of ascorbic acid (AA), glutathione (GSH), citric acid, glucose and the activity of lactate dehydrogenase (LDH) in the juice of just-ripe orange fruits (Citrus sinensis) from the two environments were investigated by standard methods. The estimated values were analyzed using student t-test and the results expressed as mean ± standard deviation. Results: The results obtained revealed that there was no significant (p≥0.05) difference in the mean pH values, ascorbic acid and glucose concentrations of the fruit juice from the two areas studied. Mean concentrations of glutathione and citric acid in the juice from Ebocha (0.44±0.09 and 18.80±1.14mg/l) were significantly (p≤0.05) lower than the values in the juice from Uvuru (0.66±0.10 and 21.43±2.02 mg/l), respectively. The results also showed that the mean activity of lactate dehydrogenase was significantly higher in the juice from Ebocha (7.033+/-1.73 U/l) than in that from Uvuru (5.344±1.74 U/l). Conclusion: The findings of this study are suggestive of a possible alteration in the metabolic activities of Citrus sinensis trees evident in its fruit juice due to the PHC pollution in Ebocha in the Niger Delta.

Effect of Chronic Exposure to Petroleum Hydrocarbon Pollution on Oxidative Stress Parameters and Histology of Liver Tissues of Native Fowl (Gallus domesticus).

The effect of chronic exposure to petroleum hydrocarbon (PHC) pollution on the concentrations of glucose, serum and liver malondialdehyde (MDA), protein carbonyl and the histology of liver tissues of the native fowl (Gallus domesticus) from Egbema in the Niger Delta Area (NDA) was studied. Identical fowls from an unpolluted area of Mbaise served as the control. Results showed no significant difference (P<0.05) in the mean glucose concentration obtained for fowls from both environments. The values obtained for serum and liver MDA and protein carbonyl for the test and control fowls were found to be significantly (P<0.05) different. There were elevated concentrations of MDA, protein carbonyl in the serum as well as MDA from liver homogenates of fowls from Egbema when compared to those of fowls from Mbaise. Histological changes were also observed in the liver sections of fowls from Egbema as against none in the liver sections of fowls from Mbaise. These changes were characteristically necrotic and inflammatory. Thus, the findings from this study show, in clear terms, that PHC pollution (crude oil and gas flaring) markedly affected the Egbema environment and induced changes in tissues of the native fowl whose nativity and ancestry are from there.

Laboratory scale bioremediation of petroleum hydrocarbon – polluted mangrove swamps in the Niger Delta using cow dung

Aims: The aim of the study was to carry-out laboratory–scale bioremediation of petroleum hydrocarbon polluted mangrove swamps using cow dung as source of limiting of nutrients. Methodology and Results: In a 70 days study, the cow dung treated polluted soil had its total culturable hydrocarbon utilising bacterial/fungi, heterotrophic bacterial and fungal counts increased progressively from the 28th day to the 70th day. The control set- up showed very slight increment in its microbial growth. Alkaline pH was observed in all the treatments and control during the study period. The conductivity values of cow dung decreased progressively. In the cow dung treatment option, the nitrate concentration decreased from 35.44 mg/kg to 14.28 mg/kg. Phosphate concentration of cow dung option decreased from 25.41 mg/kg to 9.31mg/kg. The control had the nitrate decreased from 8.42 mg/kg to 6.98 mg/kg. Percentage total organic carbon (% TOC) in the cow dung option decreased from 4.06% to 0.96%. Control experiment had the % TOC decreased from 3.32% to 2.99%. Studies using Gas chromatographic analyses showed that 0%, 49.88%, and 69.85% of Total petroleum hydrocarbon (TPH) were lost at zero hour, 28th day and 70th day respectively in the cow dung option. In addition, in the control experimental set-up, 0%, 7.14% and 13.42% of TPH were lost at zero hour, 28th day and 70th day respectively. Conclusion, significance and impact of study: The use of organic nutrient sources such as cow dung has shown good promises in bioremediation of crude oil impacted Mangrove Swamps in the Niger Delta. The next line of action is to transfer the technology to pilot scale study.