Objective: To explore the influence of high fluoride exposure on reproductive hormones in male living in endemic fluorosis villages in China.
Methods: A cross sectional study was conducted in Tongxu county in Henan Province, China. Endemic fluorosis villages and control villages were selected by random sampling according to fluoride concentration in drinking water and the prevalence of endemic fluorosis. Local male residents aged from 18 to 50 years old who were born and grew up in the investigated villages were recruited as subjects by cluster sampling. Fasting blood and urine samples were collected. The serum level of GnRH was detected using ELISA. The serum level of luteinizing hormone (LH), follicle-stimulating hormone (FSH), estradiol (E2), and testosterone (T) were determined by chemiluminesence immunoassay (CLIA).
Results: The serum levels of FSH were 7.82 mlU/ml, 10.20 mIU/ml and 9.57 mIU/ml in male from defluoridation villages (DFPG), high fluoride villages (HFG) and control villages (CG) respectively. FSH level in male from DFPG was significant lower than that from HFG and CG (P<0.05). The serum levels of E2 were 33.67 ng/mL, 29.17 ng/mL and 28.99 ng/mL in DPFG, HFG and CG respectively. E2 level in male from DFPG was significant higher than that from HFG and CG (P<0.05). Serum levels of E2 in CG were associated with LH (r=0.343, P=0.000), age (r=0.195, P=0.015), and inversely associated with serum FSH (r=-0.237, P=0.003), whereas this correlation was not observed for serum E2 level in DFPG and HFG.
Conclusion: Long-term fluoride exposure in drinking water may influence the reproductive hormones in males living in endemic fluorosis villages.