مشخصات پژوهش

Cadmium (Cd) is one of the heavy metals that, due to its toxicity, bio-accumulative nature, and long biological half-life, is considered a priority environmental pollutant worldwide and a serious threat to both human health and wildlife. Although its use has been significantly restricted in many developed countries, cadmium is still employed in specific industrial applications. Among its biological targets, the male reproductive system is particularly vulnerable and directly targets sperm cells, rendering them dysfunctional, immotile, or dead. Despite existing literature, limited attention has been given to the time-dependent nature of these effects at a defined concentration. Building on this gap, the present study investigates time-dependent changes in sperm viability following cadmium exposure. Sperm samples obtained from adult male mice were exposed to a single concentration of 170 µM CdCl2 for 30, 60, 90, and 120 minutes in an in vitro culture system. Sperm viability was assessed using the Eosin-Nigrosine staining method. The results indicated that sperm viability remained relatively unchanged during the first 30 minutes of cadmium exposure compared to the control. However, a marked decline of approximately 40% in viability was observed after 60 minutes. At 90 and 120 minutes, nearly 80% of the sperm cells were non-viable, indicating a progressive time-dependent cytotoxic effect. The present study demonstrates a clear time-dependent toxic effect of cadmium on the viability of mouse sperm. These findings emphasize the importance of considering exposure duration in toxicological evaluations. Therefore, it is essential to reassess the duration of exposure to this metal and to investigate molecular pathways in future studies.