Publication:

Fluorosis and its impact on thyroid hormones: a cross-sectional study in Bankura District, West Bengal, India

Background Fluorosis is an important public health problem in India. Fluoride ions can interact with iodide which can leads to abnormal thyroid function.

Methods The present descriptive, community based study was conducted over a period of 1 year and 6 months in the endemic and non-endemic areas of Bankura district with the sample size of 200. High serum fluoride level (≥0.02 mg/L) was also noted in fluorosis endemic areas (39%) with respect to non-endemic areas (3%). Thyroid profiles were investigated among the participants.

Results Hypothyroidism was found to be higher in proportion in endemic regions (34%) with respect to non-endemic regions (20%). The levels of serum TSH, fT4 and fluoride in endemic areas were correlated significantly with non-endemic areas. Fluoride level was found to be in significant positive correlation with TSH level and in negative significant correlation with fT4 and fT3.

Conclusions High fluoride level could produce hypofunctioning of thyroid gland and so hypothyroidism was found to be higher in proportion in fluorosis endemic areas in respect to non-endemic areas.