Let your elected representatives know that you want to keep corn-based ethanol out of your vehicles.

The EPA is considering allowing a higher amount of corn-based ethanol in gasoline.

RODALE NEWS, EMMAUS, PA—If you own a car, a boat, a motorcycle, a moped, a gas-powered lawnmower, or any other vehicle that runs off gasoline, you might want to shoot an email to your senators and congressmen. The U.S. Environmental Protection Agency (EPA) is considering a proposal to increase the allowable amount of ethanol in gasoline from the current 10 percent limit to 15 percent. And while, in light of the horrific oil leak in the Gulf of Mexico, that may sound like a good way to ease our dependence on oil, environmentalists and vehicle manufacturers alike are fighting the proposal. Their concerns, respectively: creating corn-based ethanol adds to climate change, and burning it can seriously gum up gasoline engines.

THE DETAILS: The proposed increase actually came from an ethanol lobbying group called Growth Energy back in March 2009, at which point the EPA told the group that tests needed to be conducted to see if all gasoline-powered engines could tolerate a higher blend of ethanol. EPA first delayed a final decision in December 2009 and, at the end of June 2010, delayed the decision again, stating that the agency still had not completed its testing. However, the EPA is now estimating that the Department of Energy will complete its tests of 15-percent ethanol blends (also called E15) in vehicles manufactured before 2007 by the end of September; newer vehicles can already tolerate higher ethanol blends, according to the EPA.

WHAT IT MEANS: Stopping the EPA from bowing to Growth Energy's attempts to increase ethanol concentrations is one hope where environmentalists and auto companies can find common ground. "The way it's produced right now, corn ethanol contributes more to global warming pollution than gasoline," says Kate McMahon, energy policy campaigner for the environmental nonprofit Friends of the Earth, which has been studying the dangers of ethanol for a few years. "Despite its reputation as a homegrown 'renewable fuel,'" she says, "it's not necessarily cleaner." Producing ethanol from corn requires thousands of pounds of petroleum-based fertilizers, the process of converting it into gasoline is extremely energy-intensive (and often powered by polluting coal), and it's a less-efficient fuel than gasoline. A gallon of ethanol has a third less energy than a gallon of gasoline, McMahon says. The EPA has even conducted studies finding that global-warming emissions would increase if the use of ethanol increased. All this says nothing of what ethanol does to the Gulf of Mexico. "As horrible as the tragedy in the Gulf is today, it was already in pretty bad shape before the oil spill," she says. Nitrogen-heavy fertilizers used on corn frequently run off into the Mississippi River, she notes, which then carries oxygen-deprived water to the Gulf, creating a massive dead zone there where no wildlife can survive.