Fluoride Action Network


1. Fluoride toxicosis was induced in young rats of the Long-Evans strain. Ten rats received a total of 406.47 mg. each of sodium fluoride injected intraperitoneally over a fifteen-day period, to induce acute poisoning. Seven rats survived, of which six were analyzed for this study. Ten others received a total of 1131.65 mg. each in 100 days, under which chronic regimen five survived.

2. Weight gain of the animals, their appearance, and the gross structure of the liver, kidney, pancreas, adrenal, and thyroid were not significantly different from those in the sodium chloride-injected controls.

3. Histologically, the kidney was the site of greatest damage and showed interstitial edema, tubular destruction, and hyperemia (glomerular and medullary). The pancreas showed increased width of connective tissue septa and evidence of increased mitosis of acinar cells. The thyroid gland was mildly atrophic. In the acutely fluorosed rats there was evidence of adrenal cortical hypertrophy, and the adrenal gland weight was increased in both groups. The liver remained histologically unchanged.