Switching from gasoline to ethanol may actually create dirtier air and slightly more smog-related deaths, according to a recent study reported on by the Associated Press. The “green alternative fuel” may cause nearly 200 more people to die yearly from respiratory problems if all vehicles in the United States ran on a mostly ethanol fuel blend by 2020, the research concludes. Yet, the study author acknowledges that such a quick and monumental shift to plant-based fuels is next to impossible. Each year, about 4,700 people, according to the study’s author, die from respiratory problems from ozone, the unseen component of smog along with small particles. Ethanol would raise ozone levels, particularly in certain regions of the country, including the Northeast and Los Angeles. The study by Mark Jacobson, a Stanford University civil and environmental engineering professor, troubles some environmentalists. Roland Hwang of the Natural Resources Defense Council, said that ethanol, which cuts one of the key ingredients of smog and produces fewer greenhouse gases, is an important part of reducing all kinds of air pollution. The AP reports that Hwang, an engineer who used to work for California’s state pollution control agency says “There’s nothing in here that means we should throw away ethanol.”