Effect of long-term exposure to fluoride in drinking water on risks of bone fractures

J Bone Miner Res. 2001 May;16(5):932-9. doi: 10.1359/jbmr.2001.16.5.932.

Abstract

Findings on the risk of bone fractures associated with long-term fluoride exposure from drinking water have been contradictory. The purpose of this study was to determine the prevalence of bone fracture, including hip fracture, in six Chinese populations with water fluoride concentrations ranging from 0.25 to 7.97 parts per million (ppm). A total of 8266 male and female subjects > or =50 years of age were enrolled. Parameters evaluated included fluoride exposure, prevalence of bone fractures, demographics, medical history, physical activity, cigarette smoking, and alcohol consumption. The results confirmed that drinking water was the only major source of fluoride exposure in the study populations. A U-shaped pattern was detected for the relationship between the prevalence of bone fracture and water fluoride level. The prevalence of overall bone fracture was lowest in the population of 1.00-1.06 ppm fluoride in drinking water, which was significantly lower (p < 0.05) than that of the groups exposed to water fluoride levels > or =4.32 and < or =0.34 ppm. The prevalence of hip fractures was highest in the group with the highest water fluoride (4.32-7.97 ppm). The value is significantly higher than the population with 1.00-1.06 ppm water fluoride, which had the lowest prevalence rate. It is concluded that long-term fluoride exposure from drinking water containing > or =4.32 ppm increases the risk of overall fractures as well as hip fractures. Water fluoride levels at 1.00-1.06 ppm decrease the risk of overall fractures relative to negligible fluoride in water; however, there does not appear to be similar protective benefits for the risk of hip fractures.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Aged
  • Asian Continental Ancestry Group*
  • Bone Density
  • China / epidemiology
  • Female
  • Fluoridation / adverse effects
  • Fluorides / adverse effects*
  • Fractures, Bone / chemically induced
  • Fractures, Bone / epidemiology*
  • Hip Fractures / chemically induced
  • Hip Fractures / epidemiology
  • Humans
  • Male
  • Middle Aged
  • Prevalence
  • Risk Factors
  • Spinal Fractures / chemically induced
  • Spinal Fractures / epidemiology
  • Time Factors

Substances

  • Fluorides