Total Fluoride Intake by Children from a Tropical Brazilian City

Abstract

The main sources of fluoride intake by children are fluoridated water and toothpaste. Little has been studied regarding fluoride intake from these sources in regions with tropical climates and high temperatures throughout the year. This study aimed to determine the amount of fluoride ingested from diet and tooth brushing by children who live in a city with a tropical climate. Sixty-seven children from Teresina, Piauí, Brazil, took part in this study. The city's water supply was optimally fluoridated. The duplicate-diet method was used to determine the fluoride intake from diet. The intake of fluoride from dentifrice was determined by subtracting the amount of fluoride placed on the toothbrush and that recovered after brushing. The concentration of fluoride was measured using an ion-specific electrode and is expressed as milligrams/kilogram of body weight/day. The mean (±SD) total amount was 0.071 ± 0.036 mg F/kg body weight/day, and the relative contributions of diet and toothpaste were 0.025 ± 0.010 and 0.046 ± 0.035, respectively. The factors associated with fluoride intake from toothpaste were: use of children's toothpaste (p = 0.003), use of large amounts of toothpaste (p < 0.001), and a high frequency of tooth brushing (p = 0.003). Sixty-four percent of children had an intake of less than 0.07 mg F/kg body weight/day, which is considered the upper limit for an aesthetically tolerable fluorosis risk. The results suggest that the amount of fluoride ingested by most children who live in a Brazilian city with a tropical climate is considered safe in terms of the risk of dental fluorosis.

Is the fluoride intake by diet and toothpaste in children living in tropical semi-arid city safe?

“…This result is in disagreement with other studies conducted in Northeastern Brazil 8,10 as well as in other Brazilian regions, 6,18,19,23,24 where higher values were observed. In the present study, flavored toothpaste was the most frequently used and almost all children brushed at least twice a day, factors that have been cited in the literature as associated with the risk of fluorosis.…”

“…al. 10 , who found that dentifrice was the largest source in a sample of the same city. A study is therefore needed to assess the total fluoride intake in children of low socioeconomic status, as they may be exposed to higher levels of fluoride.…”

“…One of the limitations of this study was that it was performed on two non-consecutive days, with an interval of two months between each collection, unlike other studies that collected data on two consecutive days 6,10,18,22 to improve the accuracy of the information. An attempt to reduce this limitation was made by collecting food samples on days that parents were at home, as was done in the study by Oganessian et al 31 Another advantage is diet stability, since on consecutive days the type of food eaten can be similar.…”

“…8,9,10 Omena et al 8 evaluated fluoride intake from drinking water and from fluoride toothpaste, without considering Declaration of Interests: The authors certify that they have no commercial or associative interest that represents a conflict of interest in connection with the manuscript.…”

“…9 reported fluoride intake from the entire diet (water, other beverages and solid foods) and fluoride toothpaste in a city with naturally fluoridated water. In addition, Lima et al 10 evaluated fluoride intake from diet (liquid and solid foods) and fluoride toothpaste in a city with artificially fluoridated water; however, the authors reported a low intake of water maybe because children spent most of their time in the classroom. Furthermore, another study developed in a city with tropical semi-arid climate found an increase in cases of dental fluorosis with esthetically undesirable appearance.…”