For example, it takes 12 hours to eliminate the ethanol in a bottle of wine, giving 12 hours or more of acetaldehyde exposure. A study of 818 heavy drinkers found that those who are exposed to more acetaldehyde than normal through a defect in the gene for alcohol dehydrogenase are at greater risk of developing cancers of the upper gastrointestinal tract and liver.[8] There are many associations between alcohol drinking and different types of cancer. Data from 2009 indicated 3.5 percent of cancer deaths in the U.S. were due to consumption of alcohol.[9]