Public-health risks from tea drinking: Fluoride exposure.

Aims: Due to new evidence on fluoride neurotoxicity during early life, this study examined maternal exposure to fluoride through tea consumption in a low-fluoride region and measured fluoride releases from commercially available teas (tea bags and loose teas) to determine the need to limit fluoride exposure.

Methods: Maternal urine fluoride (MUF) concentrations were measured in spot urine samples (=118) from first-trimester pregnant women and in prepared tea infusions made with deionised water from 33 brand teas and 57 loose-tea products, as determined by the direct method of using a fluoride-selective electrode.

Results: The fluoride concentration in the local drinking water supplies ranged from 0.10 to 0.18 mg/L, and the creatinine-adjusted MUF ranged from 0.09 to 1.57 mg/L. Seventeen per cent of the women were daily tea drinkers, and their MUFs were higher than those with no consumption (=0.002). The fluoride concentration from tea bags ranged from 0.34 to 2.67 mg/L, while loose teas showed 0.72-4.50 mg/L (black), 0.56-1.58 mg/L (oolong), 1.28-1.50 mg/L (green), and 0.33-1.17 mg/L (white tea).

Conclusions: