Biochemical and histologic changes in albino rats in response to charcoal powder exposure

Abstract

Background. In developing and under-developed countries, charcoal production predisposes workers to charcoal dust. This is a common occurrence as workers in this field are not properly protected and as such are exposed to charcoal dust through inhalation and skin contact. Charcoal comprises many components such as polycyclic aromatic hydrocarbons (PAHs). Due to the possible health risk associated with such exposure, this study was designed to determine the effects of charcoal powder of particle size 125 µm - 150 µm on certain biomarkers in male albino rats. Albino rats were used because of their similar physiology to humans. Materials and Methods. 20 albino rats weighing between 250 g and 300 g were used for this study; they were randomly distributed in 4 groups (5 rats each) and the charcoal powder was incorporated into their feed at different percentages; control, group 1 (10 % charcoal), group 2 (30 % charcoal) and group 3 (charcoal powder bedding) for 50 days. Using standard procedures and methods, the following parameters were tested: Hematological parameters, semen parameters, liver enzymes, renal function, hormones and lung histology. Results. The results indicated a decrease in the level of liver enzymes AST (IU/L) and ALT (IU/L) in group 1, group 2 and group 3 when compared to the control with the lowest value of 48.75 IU/L and 11.50 IU/L respectively recorded in group 2. Prolactin (mIU/L) had mean values of 1.73, 1.30 and 1.83 in group 1, group 2 and group 3 respectively while the control was 2.10. Testosterone (nmol/L) had a mean value of 1.18, 0.53 and 0.25 in group 1, group 2 and group 3, respectively, while the control was 0.90 with a significant difference (P<0.05). Creatinine (µmol/L) increased in group 1 and group 2 with a slight reduction in group 3 when compared to control (1.04) with a value of 1.35, 1.40 and 1.23, respectively. Total sperm count (´105/mL) had a mean value of 58.33, 50.00 and 43.25 in group 1, group 2 and group 3, respectively, while the control was 100.50. The lung histology for the treated groups revealed infiltration of inflammatory cells and thickening of inter-alveolar walls. Conclusion. Long term exposure to charcoal powder through nasal or oral route had serious effects on rats’ health, such as kidney damages, inflammation of the lungs and decrease in fertility in males primarily due to the presence of PAHs in charcoal.