EBI is a collaboration of UC Berkeley, the Lawrence Berkeley National Laboratory, the University of Illinois, and BP. Today, the biofuel ethanol represents approximately 8% of the nation’s gasoline supply.
Researchers note that understanding health impacts are equally important as calculating environmental impacts. The researchers underscore this importance related to our reliance on petroleum-based gasoline.
“Just think, if we had done a life cycle impact assessment on the human health effects of gasoline years ago we might not be in the situation we’re facing today,” said one of the lead researchers, Thomas McKone, an expert on health risk assessments who holds a joint appointment with Berkeley Lab’s Environmental Energy Technologies Division and the University of California Berkeley’s School of Public Health.
For years, ethanol has been used in urban areas and other geographic locations to reduce smog-forming and other dangerous pollutants as a result of gasoline combustion. Research comparing ethanol and gasoline emissions of dangerous pollutants such as carbon monoxide and benzene demonstrates a clear health benefit when using ethanol.
“Understanding the importance of biofuels and the dangers of continued oil dependence requires a holistic approach,” said Geoff Cooper, Vice President of Research for the Renewable Fuels Association, the nation’s leading ethanol trade group. “The current debate over ethanol’s benefits often fails to see the forest through the trees. Taken in totality, the economic, environmental, and health benefits of biofuels make a compelling case for accelerated production and use of these renewable fuels.”
Ethanol in gasoline can favorably impact mobile source emissions in at least four main air quality areas: fine particulate matter (e.g., PM2.5), carbon monoxide, toxics, and global warming.
Fine Particulate Matter (PM2.5): A Colorado study finds that with 3.5 percent oxygen (the amount found in E10 blends), the PM reduction is 36 percent for the normal fleet and 64.6 percent for the high emitters studied.
Carbon Monoxide (CO): A statistical analysis of ambient CO concentrations in areas using oxyfuels (those containing an oxygenate such as ethanol) indicates that these fuels appear to reduce local CO by an average of 14 percent nationally.
Toxics: Benzene appears to be the most significant toxic compound emitted from vehicles. EPA models indicate that a 10 percent ethanol blend can reduce benzene by 25 percent compared to conventional gasoline. In addition to a 25 percent benzene reduction, the use of 10 percent ethanol is shown by the EPA to reduce total toxic mass emissions by 13 percent.
Global Warming Emissions: According to a 2009 study by the University of Nebraska, direct effect greenhouse gas emissions were estimated to be equivalent to a 48% to 59% reduction compared to gasoline, a twofold to threefold greater reduction than reported in previous studies.