Investigating Biomarkers of Oxidative Stress in Liver, Testis, and Hearing Tissues Following Concurrent Exposure to Cadmium and High Noise Levels

Background & objectives:The combined exposure to noise and cadmium is common in industrial environments.This study aimed to assess changes in oxidative stress biomarkers in the liver, testis, and hearing tissues of adult male rats following simultaneous exposure to cadmium and loud noise.Methods: The study involved 32 male Wistar rats divided into four experimental groups (8 rats per group): 1.Control group (no exposure), 2. Group exposed to 100 dB noise (8 hours/day), 3. Group exposed to cadmium, and 4. Group exposed simultaneously to 100 dB noise and cadmium (8 hours/day) over one month.Levels of malondialdehyde (MDA) and glutathione (GSH) in liver, testis, and hearing tissues were measured using standard methods.Hearing loss was evaluated using the ABR test before exposure.Results: After 30 days, the combined exposure group showed a significant increase in MDA levels and a significant decrease in GSH levels in the liver, testis, and hearing tissues.A significant correlation was also found between MDA and GSH levels in the cadmium exposure group and the noise plus cadmium exposure group across the assessed tissues.Conclusion: This research indicated that both noise and cadmium exposure independently cause oxidative stress in rats, but combined exposure significantly heightens oxidative stress in all three tissues.These findings suggest that chemical agents like cadmium in noisy environments can enhance lipid peroxidation and weaken the antioxidant defense system.Further studies are needed to explore the effects of combined noise and cadmium exposure.