I stopped for gas today and saw these taped to the posts holding up the canape.

[RC]

48. What it really does is change the pollution produced. Ethanol is not really cleaner.

Want to Reduce Air Pollution? Don't Rely on Ethanol Necessarily

Fueling the automobile fleet primarily with ethanol rather than gasoline might increase air pollution, a new study finds

Ethanol as a fuel offers a host of potential benefits, according to its supporters. It can be grown and refined primarily in the U.S., whether made from corn, switchgrass or cellulose. It is already being used as a fuel additive—to help gasoline burn more completely and, thus, cut down on air pollution. And, because it is made from plants that pull carbon dioxide from the air, it does not add additional greenhouse gases to the atmosphere, which are driving climate change. But a new study shows that it will not help clear the nation's skies of smog; on the contrary, it could increase the levels of that dangerous pollution.

Environmental engineer Mark Jacobson of Stanford University used a computer model to assess how the air pollution in the U.S. would react if vehicles remained primarily fueled by gasoline in 2020 or if the fleet transferred to a fuel that was a blend of 85 percent ethanol and 15 percent gasoline, so-called E85. Under the latter scenario, levels of the cancer-causing agents benzene and butadiene dropped, whereas those of formaldehyde and acetaldehyde rose: In other words, it was a wash.

Because burning ethanol can potentially add more smog-forming pollution to the atmosphere, however, it can also exacerbate the ill effects of such air pollution. According to Jacobson, burning ethanol adds 22 percent more hydrocarbons to the atmosphere than does burning gasoline and this would lead to a nearly two parts per billion increase in tropospheric ozone. This surface ozone, which has been linked to inflamed lungs, impaired immune systems and heart disease by prior research, would in turn lead to a 4 percent increase in the number of ground level ozone-related deaths, or roughly 200 extra deaths a year. "Due to its ozone effects, future E85 may be a greater overall public health risk than gasoline," Jacobson writes in the study published in Environmental Science & Technology. "It can be concluded with confidence only that E85 is unlikely to improve air quality over future gasoline vehicles."

http://www.scientificamerican.com/article.cfm?id=reduce-air-pollution-do-not-rely-on-ethanol