Fluoride intake from drinking water and dentifrice by children living in a tropical area of Brazil

Abstract

Objective:To assess fluoride (F-) intake from water and toothpaste by children aged 18 to 36 months and to monitor the F- concentrations in the drinking water system in a tropical city of Brazil.Methods:Children (n=58) aged 18-36 months, all lifetime residents of Penedo, state of Alagoas, Brazil, participated in this study. Water F- analyses were carried out in 7 different occasions at least a week apart. For 2 days all the water drunk by each child was accounted for. Fluoride intake from water for each child was estimated using the mean F- concentration of water in 7 different occasions. Fluoride intake from toothpaste was estimated by subtracting the recovered post-brushing F- from the original amount placed in the toothbrush. The F- intake from water and toothpaste was estimated by dividing the total amount of F- ingested by the weight of each child.Results:The mean F- concentration in the drinking water was 0.94 ppm (mean range 0.78-1.1 ppm), which is above the 0.7 ppm recommended for this area of Brazil. Mean total F- intake from water and toothpaste was 0.128 mg F-/Kg Body Weight/day. The daily means of F- intake from water and toothpaste were 0.021 and 0.107 mg F-/Kg Body Weight, respectively. Ninety six percent of children showed F- intake above 0.07 mg F-/Kg Body Weight/day.Conclusions:Children in Penedo are at risk for developing dental fluorosis due to high F- intake from fluoridated toothpastes. Water fluoridation showed low contribution to the total F- intake. However, high water F- concentrations in the water indicate the need of surveillance of the artificial water fluoridation system.

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.…”

“…Teresina is a city that experiences high temperatures throughout the year and provides fluoridated water supply for collective use; thus, the greatest contribution to fluoride intake is from water, which is confirmed by Rodrigues et al 22 The observed value was similar to the findings of Omena et al, 8 despite differences between the ambient temperatures in the three cities. Teresina is much warmer (33.5°C to 24°C) and the fluoride concentration of the public water supply is lower (0.6 vs. 0.94 mg/ml).…”

“…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.…”

Total Fluoride Intake by Children from a Tropical Brazilian City

“…However, in tropical regions these data have been little explored [Omena et al, 2006;Rodrigues et al, 2009], wherein the first study only evaluated the fluoride intake from water and toothpaste, and the second study only had data on fluoride intake from diet. Thus, this study aimed to determine the daily amount of fluoride ingested from diet and during brushing with fluoridated toothpaste by children who live in a tropical city with high temperatures throughout the year and drink optimally fluoridated water, and to analyze the fluoride intake from toothpaste.…”

Systemic Methods of Fluoride and the Risk for Dental Fluorosis

“…Estimates of infant fluoride intake from Brazilian food are considered to be low and seldom more than 0.25 mg daily. However, in a fluoridated city (0.7 ppm), the estimated fluoride intake including the fluoride products (toothpaste and rinse) may increase and possibly reach the threshold for dental fluorosis according to the fluorosis index for the community (Omena et al, 2006). How much fluoride can result in dental fluorosis?…”