A report issued by a committee of the National Research Council shows that oxygen additives used to reformulate gasoline, required since 1990 by the Clean Air Act, have had little effect in reducing ozone pollution. The U.S. Environmental Protection Agency sponsored a study by the National Research Council, chaired by William Chameides of the Georgia Institute of Technology, to assess the effects of reformulated gasoline on ozone pollution levels. Dr. Chameides said in a council press release that while motor vehicle emissions have decreased in the past 10 years, the improvement is largely due to "...better emissions control equipment andcomponents of reformulated gasolines-other than oxygen additives."