Q: Why does Tacoma Water add fluoride to the drinking water supply?
A: Some water supplies contain naturally occurring fluoride. Tacoma Water’s sources do not contain a significant amount of natural fluoride. Therefore, after a vote of the people, we began to add fluoride to the Green River water supply in 1994 to help promote healthy teeth. The amount of fluoride we add is based upon HHS guidance and Washington State Department of Health (WSDOH) regulations.
Q: What changes have been made regarding the fluoride in our water supply?
A: HHS now recommends that utilities reduce their fluoride levels from a range of 0.7 mg/L (milligrams per liter) to 1.2 mg/L, to 0.7 mg/L.
Q: Why were the changes recommended?
A: The federal recommendation is based on the latest science and reflects a more conservative approach at balancing the benefits fluoride provides in protecting teeth against the risk of discoloring them.
Q: Why is Tacoma Water fluoridating to a level of 0.8 mg/L instead of the recommended dose of 0.7 mg/L?
A: WSDOH regulations require utilities that add fluoride to maintain a dose between 0.8 mg/L and 1.3 mg/L. In response to the revised federal recommendations, WSDOH recommends utilities in Washington lower their fluoride dose to 0.8 mg/L. WSDOH is evaluating options for allowing a further reduction to 0.7 mg/L.
Q: Is the former dose of 1.0 mg/L dangerous?
A: No. The level is not a danger to public health.