Opinion of the Scientific Panel on Contaminants in the Food Chain on a request of the Commission related to concentration limits for boron and fluoride in natural mineral waters

The Panel has been asked to advise on maximum concentrations of boron and fluoride in natural mineral waters that will not pose a health risk to consumers. The Scientific Panel on Dietetic Products, Nutrition, and Allergies (NDA) recently issued two opinions on the tolerable upper intake level (UL) for boron and fluoride. The CONTAM Panel based its advice on these UL values and did not re-evaluate these. High consumption of mineral water ranges from 0.5 up to about 2 litres per day, based on data from 3 EU countries. The CONTAM Panel noted that for mineral water, brand loyalty of consumers is a key element to be taken into consideration and it has to be assumed that always the same brand is consumed by the same individual. Therefore, even when a brand represents a limited percentage of the market share, this brand may be consumed by a limited number of consumers that will include individuals with a high intake according to the distribution of intake seen for mineral water generally. Taking into account the UL values of 10 mg boron per day for adults and 3, 4, 5, 7 and 9 mg boron per day for children aged 1-3, 4-6, 7-10 11-14 and 15-17 years, respectively, the CONTAM Panel concluded that it is very unlikely that intake by the general population including children older than 14 years would exceed these levels even at the highest reported levels in bottled water. For children from 1 to 14 years of age, a maximum limit of 1.5 mg boron/l in bottled water would protect these children from exceeding the UL. Calculating the dietary exposure of fluoride by combining a realistic high intake of mineral water of 1 litre/day with the maximum reported fluoride concentration (8 mg/l), the CONTAM Panel noted that the estimated exposure would exceed the UL for adults of 7 mg/person. The UL for a child of 1 to 3 years of age (1.4 mg/day) would be reached with the consumption of 200 ml of mineral water containing 8 mg/l. The Panel described scenarios for maximum limits for fluoride in mineral water. When a maximum limit of 1 mg/l is chosen, exposure to fluoride from bottled water in the whole population including young children would be unlikely to reach the UL values. When 5 mg/l is chosen as a maximum limit for fluoride, only the population of 15 years and older would be protected from exceeding the UL and only if exposure from other sources for this population would be negligible.