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

Abstract

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.

Urinary Fluoride Excretion in 6- to 7-Year-Olds Ingesting Milk Containing 0.5 or 0.9 mg Fluoride

“…The lack of a clear dose-response effect was most probably because of the overwhelming effect of F intake from toothpaste ingestion, which represented 51% (range 2-97%) of total weight of toothpaste dispensed at baseline [Zohoori et al, 2012]. Although in a slightly younger age group, a mean increase of 0.14 mg in UFE has been reported for 4-to 5-year-old British children when they received a 0.5-mg F tablet [Ketley and Lennon, 2001]. When considered on a weight basis, the higher increase in UFE in the latter study compared with the corresponding value in the present study for 0.5 mg F milk could be explained by the higher bioavailability of F from a sodium F tablet dose form compared with fluoridated milk, since a tablet is likely to be consumed on its own or with water and more readily absorbed from the gastrointestinal tract than when ingested in milk [Duff, 1981].…”

“…This may occur before the introduction of such a scheme when low UFE rates indicate the need for a programme [Baez et al, 2007], or during a currently active systemic fluoridation scheme when optimal usage needs to be demonstrated [Warpeha and Marthaler, 1995;Sharkov, 1999;Ketley and Lennon, 2001;Ketley et al, 2002;Phantumvanit et al, 2007]. In addition, there may be situations when there is no formal systemic fluoridation scheme but there may be concern that a community's total daily F intake, being from a number of sources (e.g.…”

“…Analysis of 24-hour urine samples obtained from 8 children aged 4-5 years, under customary dietary conditions and participating in the fluoridated milk scheme in St Helens, showed mean (SD) UFE to be 0.33 (0.15) mg F/day [Ketley and Lennon, 2000], which indicated suboptimal usage based on the WHO standard, a UFE of 0.36-0.48 mg F/day being indicative of optimum exposure for 3-to 5-year olds [WHO 1999]. A further study by the same authors in Liverpool showed a mean (SD) UFE of 0.26 (0.08) mg F/day following consumption of fluoridated milk containing 0.5 mg F, by thirteen 5-to 6-year-old children [Ketley and Lennon, 2001]. In agreement with previous studies from these authors, a mean daily UFE of 0.3 (0.10) mg F was estimated for children aged between 1.8 and 3.5 years participating in a fluoridated milk scheme in Knowsley [Ketley et al, 2002], which supports the suggestion that UFE for children participating in fluoridated milk schemes in the UK does not appear to meet the requirements for optimal F intake based on WHO guidelines.…”

Urinary fluoride excretion by preschool children in six European countries

“…However, in Haarlem and in Reykjavik it was only possible to recruit six and four children, respectively. In common with other recent similar studies (13, 14) the study samples were not chosen at random but as maximum co‐operation was essential, this was not considered a disadvantage. It was considered that those children participating in each of the study sites were not sufficiently different from the rest of the population for the sampling procedure to have any influence on the results obtained.…”

The fractional urinary fluoride excretion in young children under stable fluoride intake conditions

“…In addition, no other experimental data on FUEF values -under stable F intake conditions -for the same age group are available in published papers for comparison. There are two recent presentations to Congresses (34,35) that may be considered in this regard. The study of fluoride intake and excretion in Iranian 4-year-old children (34) showed that the average F urinary excretion was higher than 90% of measured F-intake.…”