Determination of Fluoride Intake from Urinary Fluoride Excretion Data in Children Drinking Fluoridated School Milk

Twenty–four–hour urine samples were collected from each of thirteen 5– to 6–year–old children both under customary conditions of fluoride intake (i.e. usual diet including milk containing 0.5 mg fluoride and usual oral hygiene procedures with fluoride toothpaste) and during a 4–day study period in which their customary fluoride intake was replaced with standard fluoride doses. The 24–hour fluoride excretion under customary conditions of fluoride intake was 0.30 mg and in response to fluoride doses in the range of 0.5–2.0 mg it was in the range 0.26–0.61 mg. Using data obtained during the study period for all subjects combined, the fluoride intake from all sources under customary conditions was estimated as 0.76 mg, representing a fractional fluoride excretion of 39%. It is concluded that these children are possibly receiving suboptimal amounts of fluoride.