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 ( N=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 ( p=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: Fluoride exposure among pregnant women increases with tea consumption, with likely risks of developmental neurotoxicity to their children. As the fluoride release from tea varies widely, the fluoride concentration should be indicated on tea packages in order to allow consumers to make informed decisions on minimising their fluoride exposure.

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Summary Youth is a crucial period for smoking preventive interventions. School-based interventions targeting the policy level and the sociocultural processes of smoking show promising effects in reducing smoking uptake and prevalence. This study presents findings from the qualitative process evaluation of a smoking preventive intervention, Focus, in the vocational school (VET) setting. Specifically, the study focused on contextual factors affecting the implementation of smoke-free school hours (SFSH). Participant observations and focus groups were conducted in four VETs during the implementation period October–December 2018. The data encompass participant observation field notes (n = 21 school days), student focus groups (n = 8) (aged 16–20), teacher focus groups (n = 5) and semi-structured individual interviews with VET leaders (n = 3). The study found that SFSH was not clearly communicated to students due to the educational structure and chaotic rhythm of the school days, ambivalent attitudes among teachers toward enforcement of smoking rules and lack of clear managerial support. The interplay of these factors counteracted the implementation of SFSH in the VET context. The presented contextual factors are important when interpreting the effectiveness of the Focus intervention and for informing future preventive efforts aiming to reduce smoking among youth in high risk of smoking cigarettes.