Effects of Soot Particulate Matter Inhalation on the Cerebral Cortex in Male Wistar Rats

Abstract

Background: Burning fossil fuels releases hazardous pollutants, including soot (carbon particulate matter), nitrogen oxides (NOx), and sulfur oxides (SOx). The cerebral cortex, a critical region for cognitive function, is particularly vulnerable to environmental toxins due to its high metabolic activity. This study investigated the neurotoxic effects of inhaled soot particulate matter on the cerebral cortex of male Wistar rats. Methods: Thirty-two rats were divided into four groups (n=8 per group). Group A served as the unexposed control, while Groups B, C, and D were exposed to varying concentrations of soot (1.221±0.169 mg/m³, 1.290±0.214 mg/m³, and 1.282±0.235 mg/m³, respectively) for 28 days. Brain tissues were collected on days 3 and 28 post-exposure and analyzed histologically using hematoxylin and eosin (H&E) staining. Results: The control group (A) exhibited normal cytoarchitecture with intact neurons, distinct nuclei, and prominent nucleoli. In contrast, soot-exposed groups (B–D) displayed significant pathological changes, including hypoperfusion-induced vascular congestion, neuronal degeneration, excessive vacuolation, pyknosis, and necrosis. Neurodegeneration worsened by day 28, indicating progressive damage. Conclusion: Chronic inhalation of soot particulate matter induces severe and time-dependent neurodegeneration in the cerebral cortex. These findings underscore the potential neurotoxicity of air pollution and highlight the need for stricter environmental regulations to mitigate neurological health risks.