Estimation of the fraction of an ingested dose of fluoride excreted through urine in pre-school children

Abstract

Objective: To determine the fraction of an ingested fluoride dose of 1 mg in 50 mL orange juice that is excreted through the urine (FUEF) of children aged 3-5 years. Methods: Eighty-eight controlled determinations involving 24-hour urinary collections from a total of 48 children were carried out during consecutive control and test days. Net fluoride urinary excretion due to the ingested dose was calculated as the difference between the total amount of fluoride excreted by each child on test and control days. Results: Excretion of the fluoride ingested from the single fluoride dose presented an average value of 30.7% (95% CI: 28.9-32.5%). No significant associations were found between individual FUEF values with either anthropometrical variables or urinary pH values. The average FUEF value found in the present study lies between previously reported values for infants and young adults. The epidemiological usefulness of the FUEF values in estimating daily fluoride dose in pre-school children is discussed.