The possibility that either dental fluorosis (Chapter 4) or the delayed tooth eruption noted with high fluoride intake (Chapter 4;
see also Short 1944) may be attributable at least in part to an effect of fluoride on thyroid function has not been studied. (NRC 2006, page 236)
This has been studied since the early 1900s.
The NRC Review itself cites research that has shown clear evidence that fluoride and thyroid hormones have "mutually interacting
effects" €ťon dental fluorosis (i.e Zhao et al, 1998).
Already in 1940 Floyd De Eds from the US Department of Agriculture at Stanford University showed that TSH was able to produce dental
fluorosis in rats (De Eds et al., 1940).
In another rat experiment De Eds and Wilson (1940) described the synergistic action of fluoride and thyroid upon dental fluorosis as "strikingly clearcut".
See also comment: Delayed Eruption
DeEds F, Wilson RH, Cutting WC - "Thyrotropic hormone and fluorine activity" Endocrinology 26(6):1053-1056 (1940)
DeEds F - "Insecticides, pest control, agents and spray residues in relation to the public health: fluorine toxicity"
Proceedings of the Sixth Pacific Science Congress of the Pacific Science Association, University of California, Berkeley, Stanford University, and San Francisco, July 24th to August 12th, 1939 , Page 178 - 183
DeEds F - "Factors in the etiology of mottled enamel" J Am Dental Assoc 28:1804-14 (1941)
Lin Fa-Fu, Aihaiti, Zhao Hong-Xin, Lin Jin, Jiang Ji-Yong, Maimaiti, and Aiken - "The Relationship of a Low-Iodine and High-Fluoride Environment
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McKay, FS - "Progress of the year in the investigation of mottled enamel with
special reference to its association with artesian water" J Natl Dental Assn 5:721 (1918)
Phillips PH, English H, Hart NB -"The augmentation of fluorosis in the chick by feeding desiccated thyroid" J Nutrition 10:399 (1935)
http://jn.nutrition.org/content/10/4/399.full.pdf (accessed Dec 2015)
Steyn DG - "Once More - Fluoridation" Review, University of Pretoria NUWE REEKS No.24 (1964)
Yang Y, Wang X, Guo X - "Effects of high iodine and high fluorine on children's intelligence and the metabolism of iodine and
fluorine" Chinese Journal of Epidemiology 15(5):296-8 (1994)
Wilson RH, DeEds F -"The Synergistic Action Of Thyroid On Fluoride Toxicity" Endocrinology 26:851 (1940)
Zhao W, Zhu H, Yu Z, Aoki K, Misumi J, Zhang X - "Long-term Effects of Various Iodine and Fluorine Doses on the Thyroid and Fluorosis
in Mice" Endocr Regul 32 (2):63-70 (1998)
Zhao WY -"A preliminary study of the interaction of iodide and fluoride in experimental iodide-goiter and fluorosis" Chung Hua
Yu Fang I Hsueh Tsa Chih 22(3):146-8 (1988)
Schuld A - "Is Dental Fluorosis Caused By Thyroid Hormone Disturbances? Fluoride 38(2)91-94 (2005)