Fluoride in our water...What are the health effects?

Fluoride Compromises Brain Function

Ding Y, Gao Y, Sun H, Han H, Wang W, Ji X, Liu X, Sun D. 2010. The relationships
between low levels of urine fluoride on children's intelligence, dental fluorosis in
endemic fluorosis areas in Hulunbuir, Inner Mongolia, China.
Journal of Hazardous Materials doi:10.1016/j.jhazmat.2010.12.097.

Liu YJ, Gao Q, Wu CX, Guan ZZ. 2010. Alterations of nAChRs and ERK1/2 in the
brains of rats with chronic fluorosis and their connections with the decreased capacity
of learning and memory. Toxicology Letters 192: 324-329.

Also observed was an inverse association between urine fluoride levels and IQ: a 0.59-point decrease in IQ was observed for each 1 mg/L increase in urine fluoride. Thus, low levels of fluoride in drinking water, even within the range of levels currently allowed, negatively impact children's intelligence and dental health.

Increased risk of fluorosis from infant formula reconstituted with fluoridated water

Levy SM, Broffitt B, Marshall TA, Eichenberger-Gilmore JM, Warren JJ. 2010.
Associations between fluorosis of permanent incisors and fluoride intake from
infant formula, other dietary sources and dentifrice during early childhood.
Journal of the American Dental Association 141(10): 1190-1201.

According to the authors, fluorosis was associated with "higher consumption of powdered concentrate formula and higher fluoride levels in the water used to reconstitute the formula." The majority of participants in this study lived in areas with "optimally" fluoridated water. The authors state that formula prepared with "low-fluoride-content water would result in much less fluoride ingestion and, presumably, substantially less or milder dental fluorosis." Also reported was an increased risk of fluorosis due to higher intake of fluoridated toothpastes between 16-36 months

Fluoride decreases bone strength

Chachra D, Limeback H, Willett TL, Grynpas MD. 2010. The long-term effects of
water fluoridation on the human skeleton. Journal of Dental Research 89(11):
1219-1223.

UCS and yield stress declined with increasing fluoride content of bone, indicating that bone strength decreases with increasing bone fluoride level.

Fluoride increases serum lead concentrations

Sawan RMM, Leite GAS, Saraiva MCP, Barbosa Jr. F, Tanus-Santos JE, Gerlach RF. 2010.
Fluoride increases lead concentrations in whole blood and in calcified tissues from lead-exposed rats.
Toxicology 271(1-2): 21-26.

After 81 days there were significantly higher blood lead concentrations, and two- to threefold higher lead concentrations in calcified tissues, in the F+Pb Group compared to the Pb Group. Thus, a biological effect not yet recognized may underlie the association between water fluoridation and increased blood lead levels observed in children.

Fluoride disrupts cardiac function

Varol E, Akcay S, Ersoy IH, Koroglu BK, Varol S. 2010a. Impact of chronic fluorosis on left
ventricular diastolic and global functions. Science of the Total Environment 408(11): 2295-2298.
Varol E, Akcay S, Ersoy H, Ozaydin M, Korogly BK, Varol S. 2010b. Aortic elasticity is impaired in
patients with endemic fluorosis. Biol Trace Elem Res 133: 121-127.

Elevated levels of fluoride in the blood lower the availability of calcium to the body, which can impair cardiac function. In cases of acute fluoride poisoning, for example, the levels of available calcium can be so low as to cause cardiac arrest. Exposure to sub-acute levels of fluoride may have more subtle effects on the heart. Research by Varol et al. (2010a) found that fluorosis patients had significantly higher urine fluoride levels than controls, as expected. In addition, left ventricular myocardial performance index (MPI), calculated as (isovolumic contraction time+isovolumic relaxation time)/aortic ejection time, was also significantly higher in fluorosis patients than in matched controls, suggesting that patients with endemic fluorosis have left ventricular diastolic and global dysfunctions.

A related study by Varol et al. (2010b) found significantly lower aortic strain (AS) and aortic distensibility (AD), but significantly higher aortic strain index (ASI) in endemic fluorosis patients than in controls, indicating that the elastic properties of the ascending aorta are impaired in patients with endemic fluorosis. Thus sub-acute exposures to fluoride may manifest as cardiac dysfunction, potentially increasing future risks of cardiac-related problems.

Fluoride as a pro-inflammatory factor

Gutowska I, Baranowska-Bosiacha I, Baskiewicz M, Milo B, Siennicka A, Marchiewicz M,
Wiszniewska B, Machalinski B, Stachowska E. 2010. Fluoride as a pro-inflammatory factor
and inhibitor of ATP bioavailability in differentiated human THP1 monocytic cells.
Toxicology Letters 196: 74-79.

Thus fluoride may be considered pro-atherogenic and pro-apoptotic, and long-term exposure to low concentrations of fluoride may lead to harmful changes in cellular metabolism.

Source:  http://fluoridealert.org/fan.2010.review.html