Cadmium (Cd) is a heavy metal that exerts a variety of toxic effects, chronic and acute, in exposed organisms. The aim of this study was to investigate the carcinogenic potential of Cd in the palatal and gingival epithelium of Wistar rats. Two groups of animals were studied: group 1 consisted of 5 rats exposed to cadmium chloride (CdCl2) in drinking water (300 mg/L) for 6 months; group 2 also consisted of 5 rats placed in the same conditions as those of group 1, but kept free of Cd for 6 additional months. Two other groups (C1 and C2) with the same number of animals, but not exposed to CdCl2, were used as a control for groups 1 and 2, respectively. All animals were weighed before and after the experimental period. After animals being killed, tissues of interest were fixed in solution of 10% formalin, processed by standard histologic techniques, stained with HE, and analyzed under light microscopy using karyometric and stereologic parameters. Loss of body weight, atrophy of the gingiva and soft-palate epithelium were the principal findings of this study, and verified only in the group 1 (p < 0.05). In conclusion, at the concentration tested, Cd presented no carcinogenic effect on the oral tissues within the experimental time period.
Cadmium chloride; Ooral cancer; Carcinogenesis; Rat
