Fluoride

FL: Fluoride and the Renal System (2010)

• Assessment
  What are the effects of fluoride exposure (intake) on the renal system at different levels (among different age groups)?

  • Conclusion

    Research on the relationship between ingestion of fluoride and renal function is limited by several factors including:

    • Most of the studies were of neutral or negative methodological quality
    • Few studies report precise individual levels of fluoride ingestion
    • None of the studies were of U.S. populations.

    The research suggests that ingestion of lower levels (conservatively, lower than 1 to 1.5ppm) of fluoride in healthy subjects is not associated with renal impairment.

    The very limited research does suggest an association between ingestion of higher levels (2.2ppm in a single study, though there is no clear definition of "higher levels" obtainable from the research) of fluoride in drinking water and fluorotoxic effects in subjects with impaired renal function. However, the research suggests that this association may be the result of impaired fluoride excretion by subjects who already have some form of renal compromise.

  • Grade: III
    • Grade I means there is Good/Strong evidence supporting the statement;
    • Grade II is Fair;
    • Grade III is Limited/Weak;
    • Grade IV is Expert Opinion Only;
    • Grade V is Not Assignable.
    • High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
    • Moderate (B) means we are moderately confident in the effect estimate;
    • Low (C) means our confidence in the effect estimate is limited;
    • Very Low (D) means we have very little confidence in the effect estimate.
    • Ungraded means a grade is not assignable.
  • Evidence Summary: What are the effects of fluoride exposure (intake) on the renal system at different levels (among different age groups)?
    • Detail
    • Quality Rating Summary
      For a summary of the Quality Rating results, click here.
    • Worksheets
      • Coplan MJ, Patch SC, Masters RD, Bachman MS. Confirmation of and explanations for elevated blood lead and other disorders in children exposed to water disinfection and fluoridation chemicals. Neurotoxicology. 2007 Sep; 28 (5): 1,032-1,042
      • Harinarayan CV, Kochupillai N, Madhu SV, Gupta N, Meunier PJ.  Fluorotoxic metabolic bone disease: An osteo-renal syndrome caused by excess fluoride ingestion in the tropics.  Bone. 2006; 39: 907-914.
      • Ludlow M, Luxton G, Mathew T. Effects of fluoridation of community water supplies for people with chronic kidney disease. Nephrol Dial Transplant. 2007; 22: 2,763-2,767.
      • Nicolay A, Bertocchio P, Bargas E, Coudore F, Al Chahin G, Reynier JP. Hyperkalemia risks in hemodialysed patients consuming fluoride-rich water. Clin Chim Acta. 1999; 281(1-2): 29-36.
      • Singh PP, Barjatiya MK, Dhing S, Bhatnagar R, Kothari S, Dhar V. Evidence suggesting that high intake of fluoride provokes nephrolithiasis in tribal populations. Urol Res. 2001; 29(4): 238-244.
      • Torra M, Rodamilans M, Corbella J. Serum and urine fluoride concentration: Relationships to age, sex and renal function in a non-fluoridated population. The Science of the Total Enviornment. 1998; 220: 81-85.
      • Xiong XZ, Liu JL, He WH, Xia T, He P, Chen SM, Yang KD, Wang AG. Dose effect relationship between drinking water fluoride levels and damage to liver and kidney functions in children. Environmental Research. 2007; 103: 112-116.
  • Search Plan and Results: FL: Fluoride and the Renal System 2009