Toxicological assessment of crude oil vapour and the modulating effect of vitamin E on the heart of albino rats

This study investigates the effect of vapour of various concentrations of crude oil and oral co-administration of vitamin E on the heart of albino rats. Thirty (30) albino rats were randomly grouped into six (6) of five (5) rats each and designated A to E. Rats neither exposed to crude oil vapour nor oral administration of vitamin E, rats exposed to oral administration of 15 mg/kg bw vitamin E but not exposed to vapour of crude oil were designated groups A and B. Rats exposed to oral co-administration of vitamin E and vapour of 25%, 50%, 75% and 100% crude oil were designated groups C, D, E and F respectively. Rats’ treatment was over a period of 28 days, after which the rats were euthanized for biochemical analyses. Serum total protein (TP), total cholesterol (CHOL) and triglycerides (TRIG) levels were determined. Standard enzyme assay was conducted for alanine transaminase (ALT), aspartate transaminase (AST), gamma glutamyl transferase and lactate dehydrogenase (LDH) of the heart. Generally, the concentration of TP of serum of other groups of rats, except group B, was significantly higher relative to the Control (p≤0.05). Serum CHOL and TRIG levels increased as the concentration of crude oil increased. Heart AST activities of rats in groups A, B and C were not significantly different (p≤0.05), similarly the AST activities of heart of rats in groups D, E and F were not significantly different (p>0.05). There was no significant difference between the gamma glutamyl transferase (GGT) activity of Control rats not exposed to crude oil vapour and not given oral administration of vitamin E (A) and the Control in Group B (given oral administration of vitamin E but not exposed to crude oil vapour). The specific activity of lactate dehydrogenase (LDH) of heart of both control rats and those of rats exposed to the vapour of various concentrations of crude oil were not significantly different (p>0.05). Experimental evidence from this study revealed that vapour of crude oil can induce biochemical changes in the heart of rats while oral co-administration of vitamin E could reduce the risk posed by exposure to vapour of crude oil by 50%.