The Competitive Enterprise Institute has published a study by Frances B. Smith on the unintended consequences of government policies to subsidize and mandate ethanol use. Actual or likely unwanted effects of political programs to promote ethanol production and consumption include:

• Spikes in food and feed costs
• Spikes in land costs
• Reduced competitiveness of U.S. farm exports
• Reduced global food security
• Loss of wildlife habitat
• Increased emissions of the carcinogen acetaldehyde

A copy of the study may be obtained here.