Members of Clean Water California were successful in convincing San Francisco and East Bay water municipalities to add an infant formula fluorosis warning to annual water quality statements.
The language is quite guarded (naturally, they're worried about lawsuits) but infant formula fluorosis warnings are an important first step in raising public awareness about the detrimental health effects of water fluoridation.
Fluoridated drinking water contains up to 250 times more fluoride than breast milk (1000 ppb in fluoridated tap water vs. 5-10 ppb in breast milk). This means that babies who ingest infant formula made with fluoridated water have a significantly elevated risk of developing dental fluorosis in their permanent teeth. A baby drinking fluoridated formula receives the highest dosage of fluoride among all age groups in the population, whereas a breast-fed infant receives the lowest. The fluorosis caused by infant exposure will generally appear on the child’s front teeth, the teeth most likely to embarrass and cause anxiety for the child if they have fluorosis stains.
The following are excerpts from studies that have found a link between infant formula made with fluoridated water and dental fluorosis.
“[F]luoride intakes during each of the first 4 years were individually significantly related to fluorosis on maxillary central incisors, with the first year most important (P < 0.01), followed by the second (P < 0.01), third (P < 0.01), and fourth year (P = 0.03).”
SOURCE: Hong L, Levy SM, et al. (2006). Timing of fluoride intake in relation to development of fluorosis on maxillary central incisors. Community Dentistry and Oral Epidemiology 34(4):299-309.
“Our data suggest that the fluoride contribution of water used to reconstitute infant feedings is a major determinant of primary tooth fluorosis."
”SOURCE: Marshall TA, et al. (2004). Associations between Intakes of Fluoride from Beverages during Infancy and Dental Fluorosis of Primary Teeth. Journal of the American College of Nutrition 23:108-16.
“Our results suggest that breastfeeding infants may help to protect against fluorosis. This is consistent with other studies that suggest that consuming infant formula reconstituted with tap water increases the risk for dental fluorosis. Importantly, this study shows that the protective effect of breastfeeding is important not only in fluoridated communities but also in nonfluoridated areas. Parents should therefore be advised that they may be able to protect their children from dental fluorosis by breastfeeding their infant and by extending the duration for which they breastfeed.”
SOURCE: Brothwell D, Limeback H. (2003). Breastfeeding is protective against dental fluorosis in a nonfluoridated rural area of Ontario, Canada. Journal of Human Lactation 19: 386-90.
“The findings of this investigation suggest that nearly 10 percent of the enamel fluorosis cases in optimally fluoridated areas could be explained by having used infant formula in the form of a powdered concentrate during the first year.”
SOURCE: Pendrys DG. (2000). Risk of enamel fluorosis in nonfluoridated and optimally fluoridated populations: considerations for the dental professional. Journal of the American Dental Association 131(6):746-55.
“The findings indicate that early mineralising teeth (central incisors and first molars) are highly susceptible to dental fluorosis if exposed to fluoride from the first and – to a lesser extent – also from the 2nd year of life.”
SOURCE: Bardsen A, Bjorvatn K. (1998). Risk periods in the development of dental fluorosis. Clinical Oral Investigations 2:155-160.
“There was a strong association between mild-to-moderate fluorosis on later forming enamel surfaces and infant formula use in the form of powdered concentrate (OR=10.77, 95% CI 1.89-61.25).”
SOURCE: Pendrys DG, Katz RV. (1998). Risk factors for enamel fluorosis in optimally fluoridated children born after the US manufacturers’ decision to reduce the fluoride concentration of infant formula. American Journal of Epidemiology 148:967-74.
“[T]he odds ratio of fluorosis on enamel zones that began forming during the first year of life was 8.31 (95% CI = 1.84, 38.59) for children exposed since birth or during the first year of life relative to those exposed after 1 year of age. The odds that a child had a maxillary central incisor with fluorosis were 5.69 (95% CI = 1.34, 24.15) times higher if exposure occurred during the first year of life compared with exposure after 1 year of age. Only those exposed to the high-fluoride water during the first year of life developed fluorosis on the mandibular central incisors… The first year of life was a significant period for developing fluorosis on the mandibular and maxillary central incisors.”
SOURCE: Ismail AI, Messer JG. (1996). The risk of fluorosis in students exposed to a higher than optimal concentration of fluoride in well water. Journal of Public Health Dentistry 56:22-7.
“It appears that, at least under some circumstances, high intakes of fluoride during the early months of life may make the difference between developing or failing to develop dental fluorosis. A study conducted in Sweden of 12- and 13-year-old children who had lived since birth in a community with 1.2 ppm of fluoride in the drinking water demonstrated that dental fluorosis was less common in those who had been breast-fed during the first 4 months of life than in those who had been fed powdered formulas reconstituted with tap water (Forsman, 1977). A somewhat similar study in the United States demonstrated that among 7- to 13-year-old children (most of them living in a community with fluoride concentration of the drinking water 1 mg/L), the prevalence of mild enamel fluorosis was significantly greater in those who had been fed concentrated liquid formula diluted with tap water during the first 3 months of life than in those who had been breast-fed during this time (Walton and Messer, 1981). It seems reasonable to conclude that the lower prevalence of fluorosis of the permanent teeth of individuals who were breast-fed during the early months of life is related to the low fluoride concentrations of human milk – concentrations less than 7 ug/L regardless of the concentration of fluoride in the women’s drinking water.”
SOURCE: Ekstrand J, et al. (1994). Absorption and retention of dietary and supplemental fluoride by infants. Advances in Dental Research 8:175-80.