Fluoride and bacterial content of bottled water vs tap water.
BACKGROUND
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.


METHODS
Comparative study.


METHODS
Cleveland, Ohio.


METHODS
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.


METHODS
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.
Lalumandier
J A
JA
Department of Community Dentistry, Case Western Reserve University, School of Dentistry, Cleveland, Ohio, USA. jal10@po.cwru.edu
Ayers
L W
LW
D001419:Bacteria / Q000254:growth & development; D015169:Colony Count, Microbial; D003257:Consumer Product Safety; D019587:Dietary Supplements; D005459:Fluorides / Q000008:administration & dosage / Q000032:analysis*; D006801:Humans; D008900:Mineral Waters / Q000382:microbiology; D009820:Ohio; D014481:United States; D014867:Water / Q000737:chemistry*; D014871:Water Microbiology
D008900:Mineral Waters; D014867:Water; D005459:Fluorides