E.P.A.
ORG
E.P.A.
The 12-member panel, which spent almost three years studying the issue at the request of the Environmental Protection Agency, did not address the health effects of the much smaller amounts of fluoride added to the drinking water of 160 million Americans to prevent tooth decay. Besides the 200,000 whose levels are four parts per million or higher, 1.4 million more are drinking water with two parts per million, a so-called secondary limit set by the E.P.A. to protect against cosmetic dental discoloration and other effects.