title: Urinary fluoride excretion by preschool children in six European countries.
abstract: OBJECTIVE
  To measure and compare 24-h urinary fluoride excretion in children aged 1.5-3.5 years from European study sites and to use these data to estimate the 24-h fluoride intake.
  
  
  METHODS
  Twenty-four-hour urine samples were collected from 3-year-old children (n = 86) who were already participating in a European multicentre study. Samples were collected from Cork, Ireland (n = 19) where the water is fluoridated to a concentration between 0.8 and 1.0 ppm and from five sites with a water fluoride concentration <0.15 ppm: Knowsley, England (n = 18); Oulu, Finland (n = 18); Reykjavik, Iceland (n = 4); Haarlem, the Netherlands (n = 6); Almada/Setubal, Portugal (n = 21). The volume of the samples was measured; they were analysed for fluoride concentration and the 24-h urinary fluoride excretion was calculated. From this an estimate of the daily fluoride intake was made.
  
  
  RESULTS
  It was found that the mean fluoride excretion in response to the usual conditions of fluoride intake in the children in the nonfluoridated areas ranged from 0.16 mg (+/-0.08) in Oulu to 0.33 mg (+/-0.27) in Almada/Setubal with an overall mean of 0.23 mg (+/-0.19). The mean 24-h fluoride excretion in fluoridated Cork was 0.37 mg (+/-0.11). There was a significant difference between the fluoride excretion in the nonfluoridated areas and that in the fluoridated areas, and the data were broadly in agreement with WHO standards.
  
  
  CONCLUSIONS
  The daily urinary fluoride excretion and estimated fluoride intake in these children appeared to be within acceptable limits.
authors.affiliation: Department of Clinical Dental Sciences, The University of Liverpool, Liverpool, UK. C.E.Ketley@liverpool.ac.uk
authors.forename: Clare E
authors.initials: CE
authors.lastname: Ketley
authors.forename: Judith A
authors.initials: JA
authors.lastname: Cochran
authors.forename: W Peter
authors.initials: WP
authors.lastname: Holbrook
authors.forename: Leonor
authors.initials: L
authors.lastname: Sanches
authors.forename: Cor
authors.initials: C
authors.lastname: van Loveren
authors.forename: Anna-Maria
authors.initials: AM
authors.lastname: Oila
authors.forename: Denis M
authors.initials: DM
authors.lastname: O'Mullane
mesh_terms: D002327:Cariostatic Agents / Q000008:administration & dosage*; D002675:Child, Preschool; D004739:England; D005387:Finland; D005457:Fluoridation; D005459:Fluorides / Q000008:administration & dosage* / Q000652:urine*; D006801:Humans; D007055:Iceland; D007494:Ireland; D009426:Netherlands; D011174:Portugal
chemical_list: D002327:Cariostatic Agents; D005459:Fluorides