European Journal of Biomedical and Pharmaceutical Sciences

ASSESSMENT OF THE IMPACT OF INHALED TOLUENE IN VAPOUR EXPOSURE CHAMBER ON RENAL AND LIVER FUNCTIONS AND OXIDATIVE STRESS IN RATS

*Olorunfemi O.J., Amah-Tariah F.S. Asara Azibalua A., Banigo Tamunotonye

ABSTRACT

This study assessed the effect of toluene inhalation on kidney and liver functions and markers of oxidative stress in rats. Twenty-four rats were grouped randomly into four groups – each group having six rats. Group 1 (control), group 2 (exposed to toluene vapour at concentration of 8,200 ppm for 14 days), group 3 (exposed to toluene vapour at concentration of 4,100 ppm for 28 days), and group 4 (exposed to toluene vapour at concentration of 2,050 ppm for 56 days). Using a whole-body vapour exposure chamber, animals in groups 2 – 4 were put through toluene vapour exposure challenge. Blood samples from rats in all groups were examined to determine the concentration of urea, creatinine, and electrolytes in serum. Likewise examined were the levels of alkaline phosphatase (ALP), aspartate transaminase (AST), and alanine transaminase (ALT) enzymes, alongside total protein and albumin in serum. The concentration in serum of markers of oxidative stress; malondialdehyde (MDA), reduced glutathione (GSH), superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT)were estimated. Data showed that when compared with the control, in the 14-day group; inhaled toluene significantly increased (p ≤ 0.05) potassium ion concentration, chloride ion concentration, and the level of urea and ALT enzyme. Also, the level of GSH and MDA (11.16±2.66) significantly increased (p ≤ 0.05) while albumin level significantly decreased (p ≤ 0.05). In the 28-day group, chloride ion concentration, urea level and AST enzyme level significantly increased (p ≤ 0.05). Additionally, the level of GSH and MDA (10.59±0.58) significantly increased (p ≤ 0.05) while ALP enzyme level significantly decreased (p ≤ 0.05).In the 56-day group, in comparison with the control, albumin level significantly decreased (p ≤ 0.05). However, no statistically significant change was observed in the concentration of potassium and chloride ions, urea, ALT, AST, and ALP levels, and in the level of GSH and MDA (1.63±0.35). These outcomes thus demonstrate a strong connection between observed concentration and duration dependent toluene vapour toxicity in the kidneys and liver, and the existence of severe oxidative stress-related tissue injury following exposure to toluene vapour.

Keywords: Toluene, Inhalation, Oxidative Stress, Vapour Toxicity, Tissue Injury.