According to a new study conducted by Life Cycle Associates, using E15 ethanol blends rather than regular gas will reduce cancer-causing pollutants and smog in Chicago’s air. The research examined and aggregated a wide range of research to assess changes in the emissions from E15 tailpipe and evaporative emissions, compared to regular gasoline. The following factors were considered for the study: ethanol blend composition; vehicle tailpipe emissions; storage and fueling with ethanol blends; changes in evaporative and exhaust emissions; human health impacts; ozone potential; and life cycle greenhouse gas emissions.

To determine how much E15 reduces the risk of cancer, the study looked at several cancer-causing pollutants found in vehicle exhaust and found that using E15 shows a projected reduction in cancer risk because the ethanol in E15 displaces carcinogens like benzene and 1,3 butadiene.

“The most significant changes from a change … to E15 include a reduction in cancer risk from vehicle exhaust and evaporative emissions, a reduction in the potential to form ozone or photochemical smog, and a reduction in greenhouse gas (GHG) emissions,” the study reported.

The study found:

• The renewable fuel in E15 displaces cancer causing emissions from gasoline, resulting in a net decrease in cancer risk of 6.6% compared to regular gas.
• The smog forming potential from E15 is lower than in regular gas.
• Using E15 gasoline with 15 percent ethanol results in a 1.5% reduction in greenhouse gas emissions compared to regular gasoline which contains 10% ethanol.

Adding ethanol also displaces gasoline components with higher smog forming potential, resulting in a lower smog forming potential for E15 blends than regular gasoline, according to the paper. In addition, the study reviewed extensive research on E15’s influence on greenhouse gas emissions, finding a reduction of 1.5 percent in E15 gasoline compared to regular, E10 gasoline. However, E15 has had difficulty gaining traction in the marketplace due to infrastructure challenges.

Those discoveries have significant implications for Chicago, which suffers from poor air quality and increased risk from disease-causing pollutants, particularly on the South Side. This study shows how the availability of E15 gasoline could help to solve those problems.

The report was supported by the Department of Energy (DOE), National Renewable Energy Laboratory (NREL), California Air Resources Board (CARB), Coordinating Research Council, Oak Ridge National Laboratory, the University of Illinois and several other institutions.