Thirty-two holstein-friesian heifers, divided into groups and fed 10, 25, 50, and 100 ppm sodium fluoride for approximately 71/2 years, were studied to determine the effect of fluoride on the hematopoietic system, liver, and thyroid gland. The composite and individual results of numerous detailed blood studies, identical to those used in evaluating the hematopoietic system in man, established that fluoride, fed daily in concentrations up to 100 ppm for more than seven years, (1) does not show gross, histological, or functional effects on the thyroid gland or liver; (2) does not produce significant changes in the serum calcium, phosphorus, or numerous other blood chemistries studied; (3) had a minimal blood effect in the form of a slightly higher total eosinophil count and a lower level of serum folic acid activity in the 100 ppm group; (4) does not produce anemia or detectable abnormalities of the bone marrow or otherwise affect the hematopoietic system.
Hoogstratten B, Leone NC, Shupe JL, Greenwood DA, Lieberman J. Effect of Fluorides on Hematopoietic System, Liver, and Thyroid Gland in Cattle. JAMA. 1965;192(1):26-32. doi:10.1001/jama.1965.03080140032008