I'm surprised (ok, not really, it's USA Today) that the article doesn't mention the hygroscopic nature of ethanol. Gasoline, being composed of various hydrocar

I'm surprised (ok, not really, it's USA Today) that the article doesn't mention the hygroscopic nature of ethanol. Gasoline, being composed of various hydrocarbons, doesn't mix with water, nor will it absorb water under normal circumstances. Ethanol is miscible with water, meaning you can mix any quantity of ethanol with any quantity of water and they won't separate. (A good example is alcoholic drinks: 2% beer and 190 proof liquor both are stable solutions.) A side-effect of being miscible with water is that ethanol is hygroscopic: it will absorb water from the air. When you mix ethanol with gasoline, the ethanol retains its hygroscopic nature, and will absorb water. This is not good. Under the right circumstances (eg marine use) the ethanol will absorb enough water to come out of solution. This is not good for engines.