The U.S. Department of Health and Human Services (HHS) recently announced its revised recommendations for the optimal fluoride level in drinking water to prevent tooth decay.   The HHS is now advising a fluoride level of 0.7 mg per liter of water instead of the once suggested 0.7 to 1.2 mg range.  The new fluoride levels were recommended because individuals have access to more sources of fluoride such as toothpaste and mouth rinses, than when water fluoridation was first introduced.