A study from the University of California Riverside’s College of Engineering Center For Environmental Research and Technology found that increasing the ethanol content in California’s gasoline from the allowable 10 percent to 15 percent will cut harmful vehicle emissions in the state.
The study showed that emissions of carbon monoxide, total hydrocarbons, and non-methane hydrocarbons declined with E15. The study said emissions of particulate matter — tiny airborne particles that pose significant health risks — also dropped significantly when cars used E15.
The study’s lead author, Georgios Karavalakis, said : “Ethanol helps provide a much cleaner combustion because it has oxygen. That’s why you have reductions in particulate emissions and in ultrafine particles, which are the very, very small particles that can be easily inhaled. They can also penetrate very deep in your respiratory system.”
Read more about the study here