The use of ethanol in gasoline has a long and sordid history ("Food or fuel?" Aug. 3). By the early 1990s, EPA regulations had reduced tailpipe emissions from new cars by over 95 percent of 970s levels, and only about 3 percent of the hydrocarbons in the atmosphere were from automobile exhausts. Nevertheless the government legislated the use of reformulated gasolines containing oxygen to facilitate complete combustion. This lead to the inclusion of MTBE in gasolines.