Low Dose Heterogeneous Chemical Mixture Exposure for the Duration of One Seminiferous Epithelial Cycle Impairs Spermatogenesis and Induce Oxidative Stress in Rat Testis

Testicular toxicity of individual chemicals is well reported, however, the toxic responses may change with the heterogeneous chemical mixture owing to the variable mode of action and interactions among the mixture components. Present study was undertaken to investigate the testicular toxicity of heterogeneous chemical mixture consisting of heavy metals and organicals following low dose exposure in rats. Adult male rats were administered vehicle (corn oil, group II) or 1/100 of LD50 value of each component of heterogeneous chemical mixture consisting of cadmium chloride, chromium trioxide, phthalic acid dibutyl ester and 1, 2-dichlorobenzene (group III) through oral gavage for 12 days to observe the spermatogenic alterations (qualitative and quantitative) and oxidative stress status of testicular tissues. Group I served as untreated control. Prominent histological alterations were noted exhibiting spermatogenesis inhibition. Seminiferous epithelial (SE) stage specific studies showed less severe cellular lesions in the tubules at SE stages V-VIII, while those at SE stages IX-XIV were most affected. Induction of oxidative stress was evidenced by the alterations in the enzymatic and non enzymatic antioxidants. The heterogeneous chemical mixture also impaired the sterodogenic enzyme functions. The studies demonstrate that even at low doses heterogeneous chemical mixture potentially induced testicular toxicity.