Abstract

This study aimed to evaluate fluoride concentrations in a variety of commonly consumed teas and Herbal infusions in Brazil and assess potential Health risks associated with their ingestion. A total of 21 samples were analyzed, including 12 loose-leaf and 9 commercially bagged products. Fluoride quantification was performed using a validated spectrophotometric method, and a deterministic and probabilistic human Health risk assessment was conducted. Fluoride concentrations ranged from 0.5 mg/L (eucalyptus) to 52.8 mg/L (hibiscus) in loose-leaf samples, and from 7.5 mg/L (anis) to 47.9 mg/L (hibiscus) in bagged products. Statistically significant differences (p<0.05) were observed in six of the nine comparable samples between formats. The non-carcinogenic risk assessment revealed that 3 out of 21 samples, hibiscus (both forms) and boldo (loose-leaf), exceeded the acceptable HQ>1. Monte Carlo simulation confirmed these findings, with hibiscus infusions showing HQ>1 in over 90% of the 10,000 iterations. Additionally, the average HI exceeded 1 in six loose-leaf and all bagged samples, with hibiscus reaching a peak HI of 18.06. These findings suggest that the consumption of certain teas and infusions, especially those with high fluoride concentrations, may contribute to excessive fluoride intake and potential health risks. The results support the need for clearer labeling and stricter regulation of fluoride content in tea and infusion products, particularly in countries like Brazil where their consumption is increasing.

Data Availability

Data is provided within the manuscript.

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    Funding

    This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior—Brasil (CAPES)—Finance Code 001 and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Grant 307791/2023–8, Grant 307791/2023-8

    Author information

    Authors and Affiliations

    Contributions

    JOP: Conceptualization; Data curation; Formal analysis; Investigation; Methodology; Roles/Writing – original draft; Writing – review & editing. GOS: Methodology; Writing – review & editing. RLB: Data curation; Formal analysis; Methodology; Writing – review & editing. LSF—Investigation; Methodology; FMRSJ: Conceptualization; Data curation; Formal analysis; Funding acquisition; Investigation; Methodology; Project administration; Resources; Supervision; Visualization; Writing – review & editing.

    Corresponding author

    Correspondence to Flávio Manoel Rodrigues da Silva Júnior.

    Competing interests

    The authors declare no competing interests.

    ABSTRACT ONLINE AT https://link.springer.com/article/10.1007/s12011-025-04817-5