Fluoride Action Network


Fluoride is an environmental chemical that has adverse effects on articular cartilage, probably increasing osteoarthritis (OA) risk. However, this association still needs more epidemiological evidence to clarify. The aim of this study was to determine the relationships between chronic fluoride exposure and OA risk among the residents living in Tongyu County, China, 2019, with a frequency-matched case–control study (186 OA patients and 186 healthy participants). The results showed that urinary fluoride (UF) (2.73?±?1.18 mg/L) was significantly higher in OA patients compared to the controls (2.35?±?1.24 mg/L) (p?<?0.002). After adjustment, the odds ratios (ORs) with 95% confidence intervals (95% CIs) between the OA risk and fluoride were calculated by the unconditional logistic regression. In full sample analysis, a 1 mg/L increase in UF level was associated with a 27% higher risk of OA (1.06–1.52, p?=?0.008), and 4th quarter’s participants were associated with higher risk when compared to 1st quarter (OR: 2.46, 95% CI: 1.34–4.57, p?=?0.003). In stratified analysis, compared to 1st quarter, 4th quarter’s participants were 4 times more likely to have OA (1.86–8.82, p?<?0.001) in the non-obese group and 7.7 times more likely to have OA (2.58–25.05, p?<?0.001) among adults???60 years. In conclusion, excessive exposure of water fluoride may increase OA risk, and could have more impact on the specific population such as non-obese, and adult aged???60 years.

Supplementary Information

Below is the link to the electronic supplementary material.

Supplementary file1 (DOCX 25 KB)

*Original abstract online at https://link.springer.com/article/10.1007%2Fs12011-021-02937-2

Data availability

The dataset used and analyzed in this study is available from the authors in reasonable request.


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We would like to thank the residents of Tongyu County especially those participants that have been included in this study. We are grateful to the authorities of Baicheng city and of the local Center of Endemic Disease Control for their supports and assistance. The authors also wish to thank Dr. Justina Ucheojor Onwuka, Dr.  Michael Boah and Ms Caselia Akiti for their comments on the draft manuscript.


This work was supported by the National Natural Science Foundation of China (81773468 and 811302389), the Wu Liande Science Foundation of Harbin Medical University (grant no. WLD-QN1703), and Postdoctoral Scientific Research Developmental Fund of Heilongjiang Province (LBH-Q17092).

Author information



AS—contributed to study design, investigation, UF measurement, statistical analysis, writing (original draft), and interpretation. XM—contributed to investigation, UF measurement, and project management. NZ and YM—contributed to investigation and UF measurement. AL, JW, and HL—contributed to statistical analysis and verification. JP and YG—contributed to conceptualization, resources, funding acquisition, writing (review and editing), and supervision. All authors discussed the results, gave comments, and approved the final manuscript.

Corresponding authors

Correspondence to Junrui Pei or Yanhui Gao.

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Ethics approval

The study was approved by the Ethical Review Board of Harbin Medical University (HMUIRB20120021). Written informed consent was obtained from each participant of the study population. The study was performed according to the Declaration of Helsinki.

Competing interests

The authors declare no competing interests.

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