Nutritional, biochemical, and histopathological study on dose and time dependent effects in fluoride exposed rats

Aim of this study was to observe the effect of fluoride (F) in Wistar rats in a dose and time-dependent manner. Male rats (n=36) were taken and were randomly divided into six groups (group I: control, group II: 5 mg/L F, group III: 10 mg/L F, group IV: 15 mg/L F, group V: 50 mg/L F, and group VI: 100 mg/L F). Animals were examined at 3-time points of 30, 60, and 90 days for F toxicity changes. The results indicated that the F induced dose and time-dependent diet intake, body weight gain, food efficiency ratio, dental fluorosis, F level in urinary, serum, bone and teeth, and histopathological changes in the tissues of liver and kidney. The significant increase in exposure of F through water in groups V and VI as compared to other groups has shown alterations in their food efficiency ratio, body weight gain, and the significant increase in the urinary, serum, teeth, bone, liver and kidney F levels. Histopathology of the kidney revealed few dilated tubules in the kidney of animals of group VI as compared to animals of all other groups. Whereas histopathology of the liver showed microvacuolation in groups V and VI compared to groups I, II, and IV. However, there were no significant differences between the organ weight ratios among all the groups. In conclusion, the dose -dependent effect of F starts at 100, 50, and 15mg/L from first, second, and third months, respectively.However, there were no significant differences in 5 and 10 mg/L F groups after 3 months.