Ethanol won't hurt engines, what it does hurt is the ole fuel lines in auto and boats that won't hold up to it, but we change them out with what will hold up. What hurts is that ethanol adsorbs moisture and can settle in a fuel tank (at the station also) or carburetor bowl (causing corrosion), so, every so often, drain your fuel bowl. Do not store for long periods of time. Now what is bad and as far as I see a crime, is that it cost more (uses more energy) to produce ethanol then the available power it produces. Mileage is lower (per GPM), so you have to burn even more. Farmers selling corn for ethanol drives up prices on all the products that corn is used for.
In 2011 an estimated 13.8 billion gallons of ethanol were produced, 3.7 billion gallons of it at 41 plants in Iowa. Ethanol production now consumes 5 billion bushels of the 12.4-billion-bushel U.S. corn crop.
So in the guise of saving the air quality, we degrade our water quality.