1. SERUM AND LIVER TISSUE HYDROCARBONS CONTENTS OF MALE RATS ORALLY EXPOSED TO BONNY LIGHT CRUDE OIL. PRESENTED BY SAVIOUR U. UFOT, Ph.D MBA BIOCHEMISTRY DEPARTMENT FACULTY OF BASIC MEDICAL SCIENCES UNIVERSITY OF CALABAR CALABAR - NIGERIA E-mail: sufot2001@yahoo.com

2. INTRODUCTION: Polycyclic aromatic hydrocarbons (PAH) are among the hydrocarbons constituents in crude oil with most dangerous environmental contaminants (Adeyemi et al., 2008, 2009). Exploration and exploitation of crude oil have caused several environmental problems arising from spillage of the oil and flaring of gas.

3. INTRODUCTION: Georgewill (2012) reported that large volumes of crude oil are spilled annually into the Niger delta creeks, thereby polluting the soil and water within the environment. The adverse effects caused by oil spillage on humans and other organisms within the affected area(s) may be attributed to the consumption of oil polluted water, contaminated agricultural produce and sea foods.

4. It has been reported that some Traditional Medicine Practioners in Nigeria claimed that crude oil has an analgesic effect that is comparable to the analgesic effect of aspirin (Orisakwe et al., 2000). Literature report indicates that crude oil may provide remedy for different types of ailments, including disorders of the gastrointestinal tract, certain types of burns, ulcers of the leg, “foot rots” as well as antidote for poisoning; and that it has the ability to drive away witchcraft (Dienye et al., 2012).

5. Direct exposure to crude oil has been reported to have an adverse effect on some biochemical and haematological properties in experimental animals. According to Dienye et al. (2012), exposure to crude oil produces a variety of complications in different organs, including liver, lungs, kidneys and the skin. Introduction Cont’d

6. It has been reported that several petroleum and petroleum products induced toxicity effects are attributed to hydrocarbon constituents of these products (Orisakwe et al., 2000; Uboh et al 2012). However, there is scarcity of information on the specific hydrocarbon constituents of Nigerian Bonny Light crude oil accumulated in the blood following oral exposures.

7. The study aimed at assessing the types and concentration of hydrocarbons accumulated in the serum and liver tissues of male rats orally exposed to bonny light crude oil.

8. MATERIALS AND METHODS: Animal Handling and Treatment: Twenty male albino Wistar rats (180–200g) were used in this study. The rats were distributed into two groups (control and test groups), with ten rats each. The test animals were orally gavaged 60mg/kg bwt of Bonny Light Crude oil (BLCO), once daily for twenty eight days, while the control animals were given distilled water.

9. MATERIALS AND METHODS: The animals, housed in plastic cages with metallic top, were kept under the prevailing normal room temperature and humidity, and a 12-h light/dark cycle.. The animals were allowed free access to standard laboratory animal pellets (Guinea Feeds, Benin, Nigeria) and water ad libitum.

10. MATERIALS AND METHODS: The BLCO used in this study was obtained from the NNPC/TOTAL/SHELL Joint venture in Port Harcourt through procedural authorization from the Department of Petroleum Resources Zonal Office, Port Harcourt, Nigeria. Animals handling and treatments in this study followed the guidelines of the Institution’s Animal Handling Ethical Committee. All the chemicals used were of analytical grade.

11. After twenty-four hours from the last exposure, the animals in both groups were sacrificed under chloroform anaesthesia, blood and liver tissues collected for analyses. The whole blood samples were collected by cardiac puncture, allowed to clot, and serum separated after centrifugation.

12. The serum and digested liver tissue samples were extracted and analysed for hydrocarbon types and concentrations. using Gas Chromatographic (GC) – Mass Spectrometry (MS) techniques as described by Tunsaringkarn et al. (2004)

13. Data Analysis: Data generated from this research work were reported as the mean values and standard deviations. The data were further computed and analyzed using one way “ANOVA” and unpaired “Student’s t-test”. The data were analyzed with the help of a statistical package, SPSS version 18.0 for Windows, and considered significant at p<0.05.

14. Group Treatment Number of Rats Males 1Distilled Water (control)10 260mg/kg body weight of crude oil10 TABLE 1 Distribution and treatment of animals in the respective groups

15. RESULTS:

20. RESULT & DISCUSION: The results showed that benzene, toluene, ethylmethylene, xylene, BTEX, pyrene, naphthalene and total polycyclic aromatic hydrocarbons (PAH) in the serum and liver tissues of rats exposed to BLCO were significantly (p<0.05) higher, compared to respectively with the concentrations in the serum and liver tissues of control rats. However, there was no significant difference (p<0.05) between the serum and liver concentrations of these hydrocarbons in both the control and test animals.

21. The reports of ATSDR (1990, 1991) and Ritchie et al. (2001) demonstrated that benzene, toluene, ethylbenzene and xylene (BTEX) are among the major aromatic hydrocarbon constituents of most petroleum products, including gasoline. NIOSH (1990), ATSDR (2007), Weisel (2010) and McHale et al. (2012) reported that most of these hydrocarbons are biotransformed into reactive metabolites by hepatic tissues metabolizing system.

22. Also, Schaumburg and Spencer (1978) earlier reported that the aliphatic and aromatic hydrocarbons which are the major constituents of petroleum products are metabolized in the liver tissue. Several tissue toxicities have been reported for petroleum polycyclic aromatic hydrocarbons in humans and experimental animals (Otitoloju and Olagoke, 2011; King et al., 2012; Osuala, 2012).

23. The results of this study indicate that these hydrocarbons, on absorption within the GIT, are relatively distributed equally within the serum and liver tissues. The results also suggest that the hydrocarbons, and/or their metabolites, are implicated in the different tissue toxicity effects reported for petroleum and petroleum products in humans and experimental animals.

24. Appreciation. To OMICS Organising Committee for the opportunity to present the result of my studies. To Associate Professor Dr. F. E. UBOH, Professors Patrick E. Ebong and Eyong U. Eyong for their guidance and support during the course of the study.

25. THANK YOU