Real-life metal mixtures: the impact on male reproductive health in Wistar rats.

This study examined the effect of a mixture of toxic metals (Cd, Pb, As, Hg, Cr, Ni) on the male reproductive system of Wistar rats. Specifically, the research included the analysis of the level of toxic metals and minerals in testicular tissue, histological analysis of testicular tissue, monitoring of testosterone, FSH and LH levels in serum, as well as measurement of aromatase enzyme activity in testicular tissue. The parameters of oxidative stress and antioxidant defense in the testicular tissue were also investigated, including the analysis of Nrf2 levels after 28 and 90 days of exposure to the mixture. The doses with which the animals were treated were based on a previously conducted human biomonitoring study. After 28 days, increased levels of Cd, Ni, As, and Cr were recorded, while after 90 days, only Cd and As levels increased. Changes in minerals were observed for Ca and Mg. Histological analysis of testicular tissue showed the existence of different morphological changes depending on the dose and length of exposure. Of the examined hormones, the most changes were observed for LH. Significant oxidative stress and antioxidant parameter changes in the testes highlighted Nrf2 signaling's role in maintaining redox balance. Although doses were considered safe, this realistic metal mixture disrupted male reproductive health, emphasizing the need to reevaluate safe exposure levels to improve overall health.