However, during this visit, Bush Lula made clear that Washington will maintain in effect a tariff of 54 cents that Americans charged for each gallon of ethanol imported from Brazil. Lula did not mention the U.S. rate, but upheld his claim on industrialized countries to eliminate the heavy subsidies which give their farmers. Alcohol Some studies consulted show that the use of ethanol (alcohol) has the potential to produce less pollutant emissions for life on Earth, under this precedent, Brazil has catapulted into the development and use of these resources, aiming at contributing to the global sanitation and the effects of global warming, and strengthen a stronger economic position internationally. But other studies ensure that the combustion of ethanol produces more greenhouse gases than gasoline, per gigajoule (International System unit for measuring energy and work), produced by the combustion of ethanol is produced 71.35 kilograms dioxide carbon, unlike gasoline, made by pure octane, which produces 67.05 kilograms per gigajoule.
(Wikipedia) In other words, the use of pure ethanol in vehicles produces 6 percent more carbon dioxide per kilometer. If there is a reduction of polluting gases, may be due to agricultural practices and biofuel production also is used as an additive for gasoline oxygenate standard, to replace methyl tert-butyl ether, responsible for the contamination of soils and groundwater. Considering this, it remains important to the environmental impact that may have the manufacture of ethanol. In 2002, monitoring conducted at ethanol plants showed that the levels of volatile organic compounds were much higher than anticipated.