The Commissioner of Food and Drugs has concluded that it is in the interest of the public health to limit the addition of fluorine compounds to foods (a) to that resulting from the fluoridation of public water supplies, (b) to that resulting from the fluoridation of bottled water within the limitation established in § 165.110(d) of this chapter, and (c) to that authorized by regulations (40 CFR part 180) under section 408 of the Act.