Fluoride and bacterial content of bottled water vs tap water

Arch Fam Med. 2000 Mar;9(3):246-50. doi: 10.1001/archfami.9.3.246.

Abstract

Context: Bottled water has become a status symbol and is frequently used in place of tap water. While both waters are considered safe to drink, is either more beneficial in preventing tooth decay and is there a difference in purity?

Objective: To determine the fluoride level and bacterial content of commercially bottled waters municipal tap water and to compare the results.

Design: Comparative study.

Setting: Cleveland, Ohio.

Sample: Fifty-seven samples of 5 categories of bottled waters were purchased from local stores. Samples of tap water were collected in sterile containers from the 4 local water processing plants. Fluoride levels were determined by an ion-selective electrode method. Water was cultured quantitatively and levels of bacteria were calculated as colony-forming units (CFUs) per milliliter.

Main outcome measure: Fluoride levels and bacterial counts.

Results: Fluoride levels within the range recommended for drinking water by the Ohio Environmental Protection Agency, Cincinnati, 0.80 to 1.30 mg/L, were found in only 3 samples of bottled water tested. The fluoride levels of tap water samples were within 0.04 mg/L of the optimal fluoride level of 1.00 mg/L. The bacterial counts in the bottled water samples ranged from less than 0.01 CFU/mL to 4900 CFUs/mL, including 6 samples with levels substantially above 1000 CFUs/mL. In contrast, bacterial counts in samples of tap water ranged from 0.2 to 2.7 CFUs/mL.

Conclusions: Five percent of the bottled water purchased in Cleveland fell within the required fluoride range recommended by the state, compared with 100% of the tap water samples, all of which were also within 0.04 mg/L of the optimal fluoride level of 1.00 mg/L. Use of bottled water based on the assumption of purity can be misguided. Recently, the Environmental Protection Agency, Washington, DC, published a final ruling that requires community water systems to regularly report to the public on the quality of local tap water; there are no similar proposals to determine the quality of bottled water through labeling.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacteria / growth & development
  • Colony Count, Microbial
  • Consumer Product Safety
  • Dietary Supplements
  • Fluorides / administration & dosage
  • Fluorides / analysis*
  • Humans
  • Mineral Waters / microbiology
  • Ohio
  • United States
  • Water / chemistry*
  • Water Microbiology*

Substances

  • Mineral Waters
  • Water
  • Fluorides