here you go.... i got the link....

http://findarticles.com/p/articles/m...0/ai_n19096127

take note of the following paragraphs:

E10 is the most commonly sold ethanol-blended gasoline in the United States. It contains 10-percent ethanol and 90-percent gasoline. Most automobile manufacturers warranty their vehicles to work with E10. At 10 percent, the ethanol generally does not cause corrosion or starting problems. But at higher concentrations, the fuel tank, pump, lines and fuel delivery system--whether a carb or fuel injection--must be designed differently. The same is true for other engines, including outdoor power equipment, though a slight carburetor adjustment may be needed.