Fluoride content of infant formulae in Australia

Abstract

The prevalence of dental fluorosis in Australia and the United States of America has increased in both optimally fluoridated and non-fluoridated areas. This has been attributed to an increase in the fluoride level of food and beverages through processing with fluoridated water, inadvertent ingestion of fluoride toothpaste, and the inappropriate use of dietary supplements. A major source of fluoride in infancy is considered to be infant formula which has been implicated as a risk factor for fluorosis in a number of studies. In this study the fluoride content of the infant formulae commonly used in Australia was determined. The acid diffusible fluoride of each powdered formula was isolated by microdiffusion and measured using a fluoride ion-specific electrode. The fluoride content of milk-based formulae ranged from 0.23 to 3.71 micrograms F/g and for soy-based formulae from 1.08 to 2.86 micrograms F/g. When reconstituted, according to the manufacturer's directions, with water not containing fluoride, the formulae ranged in fluoride content from 0.031 to 0.532 ppm, with the average fluoride content 0.240 ppm. Using average infant body masses and suggested volumes of formula consumption for infants 1-12 months of age, possible fluoride ingestion per kg body mass was estimated. None of the formulae, if reconstituted using water containing up to 0.1 ppm F, should provide a daily fluoride intake above the suggested threshold for fluorosis of 0.1 mg F/kg body mass. However, if reconstituted with water containing 1.0 ppm F they should all provide a daily fluoride intake of above the suggested threshold for fluorosis with intakes up to 2-3 times the recommended upper 'optimal' limit of 0.07 mg/kg body mass. Under these conditions the water used to reconstitute the formulae would provide 65-97 percent of the fluoride ingested. These figures are likely to be overestimates due to the intake of nutrients from other sources reducing formulae consumption and also due to the lower bioavailability of fluoride from milk-based formulae. Further, it is generally believed that the maturation stage of enamel formation is the critical period for fluorosis development by chronic, above-threshold fluoride exposure. The maturation stage for the anterior permanent teeth, however, is after the first twelve months of life where fluoride intake from infant formula consumption per kg body mass is highest. The level of fluoride in the commonly used Australian formulae would suggest that infant formula consumption alone is unlikely to be a risk factor for dental fluorosis in a non-fluoridated community, but could make a major contribution to an infant's daily fluoride intake. However, prolonged consumption (beyond 12 months of age) of infant formula reconstituted with optimally-fluoridated water could result in excessive amounts of fluoride being ingested during enamel development of the anterior permanent teeth and therefore may be a risk factor for fluorosis of these teeth.

Fluoride Analysis of Foods for Infants and Estimation of Daily Fluoride Intake

“…In planning fluoride applications for oral health, the daily fluoride intakes (DFIs) 2) from drinking water and food stuffs must be evaluated as basic data for human body as an index of routine fluoride intake. In Western countries, DFIs from foods and drinking water are evaluated for many years and monitored regularly in terms of fluoride exposure, especially in considering the occurrence of dental fluorosis 5,9,15,16,[19][20][21][22][23][24]29,30,34,35,45) . The fluoride intake of the Japanese population has been investigated by several groups since the 1950's, but the studies have been focused primarily on adults 13,32,33,36,43,44) .…”

Fluorine content of several brands of chocolate bars and chocolate cookies found in Brazil

“…This is also a critical time for ensuring that the optimal levels of ingested fluoride are not exceeded. Several previous studies have determined the fluoride content of children foods, such as milk 1,3,14,15,26,30 , dinners and desserts 6,12,21,22,25,31 and beverages 1,13,16 . However, these studies have been limited mainly to products manufactured in North America.…”

Concentração de flúor em medicamentos pediátricos e risco de fluorose dentária

“…A fluorose dentária se caracteriza por uma alteração na estrutura do esmalte, provocada pela intoxicação sistêmica de íons flúor, durante a fase de formação do esmalte 1, 5, 9,17,20,39,77,94,153,162,171,181 . Portanto, a má formação ocorre somente durante a amelogênese, e é de caráter irreversível.…”

“…Portanto, a concentração final de flúor dependerá da concentração presente na água usada para diluição. Já para as fórmulas em pó, a concentração média de flúor ocorre em torno de 0,69 ppm para os produtos à base de leite, sendo um pouco mais alta para os produtos à base de soja, devido ao maior nível endógeno de flúor no extrato da soja e à ligação do flúor ao fitato e ao fosfato tricálcio 20,21,64,89,96,110,153 . Para a reconstituição do produto, adiciona-se em média, 145 g de pó a 880 mL de água.…”

“…Os diferentes graus de comprometimento, desde asma até transplante de medula, e variados protocolos terapêuticos, requerem o uso diário de uma série de medicamentos, seja de maneira simples ou associados, até mesmo várias vezes ao dia, por um longo período de tempo ou com recorrência 41 , que precisam ser avaliados quanto ao teor de flúor. Os medicamentos prescritos são na grande maioria apresentados na forma líquida e têm sido associados, por inúmeros estudos, com a maior ocorrência da cárie dentária em quem os utiliza regularmente 41,53,145,146,154 , por conter principalmente a sacarose em sua composição e pela sua relação 19,24,30,70,71,96,98,100,101,110,123,135,148,153 .Nas condições experimentais deste estudo, considerando-se apenas os Assim, um alerta ao possível efeito colateral na área odontológica, de característica irreversível, deve ser dado ao fabricante, para que averigüe e/ou reformule tal medicamento, sem contudo modificar sua principal finalidade.Atualmente a criança é exposta a muitas fontes de flúor, além da água, principalmente devido ao uso de dentifrícios fluoretados e ao consumo de suplementos dietéticos, fórmulas infantis e alimentos e bebidas manufaturados, além da existência do "efeito halo" 69,88,117,148,168 . Oral Sci., Basel, Karger, p.24-9, 1996.…”