Toxicological Evaluation of Palm Kernel Oil (PKO) Biodiesel-Contaminated Catfish on Kidney of Albino Rats

Aim: To assess the toxicological and histopathological effects of feed formulated with catfish (Clarias gariepinus) exposed to palm kernel oil (PKO) biodiesel on kidney in albino rat.

Study Design: Randomized experimental controlled study

Place and Duration of Study: The study was carried out in Environmental Science laboratory of Federal University of Petroleum Resources Effurun between February and June, 2014.

Methodology: A total of 30 albino rats weighing 49 to 53 g and within the age range of 4-6 weeks were used for this study. Experimental rats were grouped into three, namely; Control, BD0.1 and BD0.25 placed on feed formulated with catfish exposed to borehole water mixed with different concentrations of PKO biodiesel (0 %v/v, 0.1 %v/v, 0.25 %v/v) for 30 days. Haematological properties, indices of oxidative stress, some enzymes of the kidney and selected serum indices of kidney functions (urea, creatinine, Na+ and K+) were measured. Tissue activity of ALP, ACP, LDH, CAT, GST and SOD were also estimated using conventional methods. Analyses were carried out using the SPSS software package (version11.5) and the results are expressed as mean ± SEM.

Results: The study showed that animals fed with fish exposed to PKO biodiesel significantly had reduced relative kidney weight while serum levels of Na+, K+, urea, creatinine and kidney concentration of malodialdehyde (MDA) were elevated significantly (p<0.05) when compared with the controls. Activities of selected enzymes of kidney studied were significantly lower in BD0.1 and BD0.25 rats relative to the control. Particularly, the kidney activity of alkaline phosphatase (ALP) of control, and rats fed with feed formulated with BD0.1 and BD0.25 are 188.24 ± 6.68, 156.88 ± 9.84, 149.02 ± 6.77 U/mg protein, respectively. Histological examination revealed proliferation of inflammatory cells in the kidney of experimental rat.

Conclusion: Data from this study suggested that consumption of catfish exposed to PKO biodiesel can compromise renal integrity, reduce renal performance, subject the kidney to oxidative stress and inflict varying degree of inflammation on cellular architecture of the kidney.