Answer: Mouth alcohol is when you have unabsorbed alcohol that gets exhaled in a breath sample. That occurs when either you have recently consumed alcohol and there is still some small amount left in your mouth. And that can particularly happen if there is something in your mouth, which has held onto unabsorbed alcohol. Sometimes people will have chew, they will have gum, even things like food stuck in your teeth can hold a small amount of alcohol. Mouth alcohol can also occur when unabsorbed alcohol is brought back up into the mouth from the stomach. For example, with burping is a pretty common example.
People who suffer from GERD or other serious heartburn issues are likely to be bringing up alcohol from the stomach. But that can occur at other times with burping or things like that. So, that’s when you see mouth alcohol. It can be a viable defense in Wisconsin; it does have to be handled pretty carefully. The machine, the Intoximeter II that we use here, is programmed to recognize the proper slope for an alcohol reading. It will miss mouth alcohol under specific circumstances.
If you have some alcohol that has been absorbed into your system and you also have some mouth alcohol, some unabsorbed alcohol that is being exhaled, the slope detector will not recognize that and you’re going to have a higher reading because of that unabsorbed alcohol being breathed into the machine. Even a very small amount of unabsorbed alcohol can make a large difference in a test result because the machine is looking for tiny, tiny, tiny amounts of alcohol and even a molecule of unabsorbed alcohol being breathed into the machine would drastically change the results.