Method: Using the cluster sampling technique, children aged 1-9 years were chosen from 2,000 randomly selected households in Kuwait. Questionnaires were then administered to their mothers to determine the children’s daily fluid intake. Fluoride concentrations in tap water as well as all brands of bottled water and beverages consumed by the children were measured, using the fluoride ion-specific electrode. Fluoride excretion was determined in 400 randomly selected children, based on fluoride/creatinine ratio.
Result: The mean daily fluid consumption by the children was high, being 1115 - 1545 mL. About 40% of the fluid intake was plain water, and approximately 10% of the children drank bottled water exclusively. Fluoride concentration in tap water was low (0.04 SD 0.02 ppm), but was higher in bottled water (0.28 SD 0.40 ppm). Mean daily fluoride ingestion from fluids was 0.013- 0.018 mg/kg body weight. Even after allowing for fluoride ingestion from other sources, mean daily fluoride ingestion was still below 0.1 mg/kg body weight set by the United States of American Institute of Medicine as the lowest-observed-adverse-effect level for moderate enamel fluorosis in children aged up to 8 years. Furthermore, mean daily urinary fluoride excretion of 128-220 µg was below the provisional standard of 360-480 µg for optimal fluoride usage by children aged 3-5 years.
Conclusion: Fluoride ingestion from fluids and urinary fluoride excretion by the children were below the recommendations for optimal fluoride usage. An upward adjustment of fluoride level in public drinking water supplies in Kuwait is, therefore, suggested as a caries preventive measure. This project was supported by Kuwait Foundation for the Advacement of Sciences, KFAS Project No. 2007-1302-06.