Ethanol vehicles pose significant health risk – study

Posted by Humphrey Cheung

Stanford (CA) - A new Stanford University study finds that a switch to ethanol vehicles would likely increase the number of respiratory deaths in the United States.  Stanford University scientist Mark Jacobson published his findings in the Environmental Science and Technology Journal and says that ethanol poses an “equal or greater” risk to public health over gasoline.

Jacobson simulated widespread ethanol usage with a mainframe computer, but focused his attention to the Los Angeles area because of its high pollution and population density.  His computer model combined the effects of tailpipe emission chemicals with temperatures, sunlight, clouds and precipitation.  He also calculated wind effects and the ethanol’s reaction with other airborne chemicals.

The simulation calculated two future scenarios set in the year 2020 that compared an all gasoline vehicle fleet versus one fueled by ethanol 85 which is a blend of 85 percent ethanol and 15 percent gasoline.  In the E85 scenario, the levels of the carcinogens benzene and butadiene were reduced, but two others formaldehyde and acetaldehyde rose.  Ozone also significantly increased in some parts of the country.

Jacobson points out that the increase ozone would account for an extra 200 respiratory deaths per year which is about 4 percent more than the deaths that would have been caused by gasoline vehicles.

You can read the abstract of the study here .