ABSTRACT

Formaldehyde is a  highly toxic gas with a characteristic pungent smell. It is colorless and is usually stored as aqueous solutions (formalin). It is used widely as a tissue preservative in laboratories, as a sterilizing agent, and as a disinfectant, and it's considered an occupational indoor air pollutant because it is highly volatile. The study aim to investigate the effect of formaldehyde inhalation on oxidative stress in the liver tissue of adult male wistar rats. The rats were randomly divided into four groups (A, B, C, and D) for a period of four weeks. Group A (control group) had nil exposure to formaldehyde gas. Group B animals were exposed to formaldehyde gas for a duration of 2 hours daily, Group C was exposed to formaldehyde gas for a duration of 4 hours daily and Group D was exposed to formaldehyde gas for a duration of 8 hours daily, for a period of 4 weeks respectively. At the end of the experiment, the animals were anesthetized and thereafter the liver tissues were harvested, and placed in phosphate buffer and thereafter sent for analysis of catalase, superoxide dismutase and malondialdehyde. Statistical analysis was done using graph pad prism version 8.0.1. Results were presented as mean ± standard error of mean. Analysis of variance was used to compare the means of tests and control value while post hoc test was done using Dunnett's multiple comparison test and a P-value of less than 0.05 was considered statistically significant. The results obtained from this research revealed that formaldehyde inhalation has an effect on lipid peroxidation product (malondialdehyde) and antioxidant enzyme activities (superoxide dismutase and catalase) and oxidative stress occurred in the liver tissue of the test animals in group B which had 2 hours exposure.