Loudoun County Health Department

• Frequently Asked Questions

Typically, groundwater is clean and safe for everyone to drink. Occasionally, naturally occurring constituents such as fluoride can be present in groundwater at levels that may pose either a cosmetic or health concern.

In drinking water, fluoride concentrations less than two milligrams per liter can be beneficial in helping prevent dental cavities. Fluoride concentrations above two milligrams per liter can cause tooth discoloration in children. Fluoride concentrations above four milligrams per liter in drinking water can cause health problems, such as bone disease and mottled teeth; at this level fluoride is considered a primary contaminant and should be treated prior to use as drinking water.

Fluoride concentrations in most private drinking water wells in Loudoun County are so low that they cannot be detected. However, fluoride concentrations in a few water wells have been above two milligrams per liter and, in very few wells, have shown a fluoride concentration of greater than four milligrams per liter.

Dr. David Goodfriend, Director of the Loudoun County Health Department, says everyone should know the quality of water they're drinking. The Health Department recommends that well owners know what is in their water and to consider testing their water for fluoride every three years. The cost of testing water for fluoride ranges from $15 to $75. A list of testing laboratories is available here:

• Area Fluoride Testing Labs

Residents who are served by public or community water system should contact their water supplier if they have questions about fluoride in the drinking water.

Contact Information

For more information, contact the Environmental Health Division of the Loudoun County Health Department:

Loudoun County Health Department
Environmental Health Information
1 Harrison Street, S.E., 2nd floor
Leesburg VA 20175
Phone: 703-777-0234