[MostlyStable]

The article extensively talks about the amount produced. While it has not been tested against breathalyzers, it is producing so little alcohol that it seems unlikely to be a problem. The claim in the article is that, across 24 hours, you might consume a few miligrams of alcohol, as compared to "if you swallowed 1/10th of your mouthwash, that would be ~200 milligrams of alcohol". So across the entire day, you are producing a couple orders of magnitude less alcohol than is in 1/10th of a mouthwash treatment (or 1/5th I guess if you use it twice a day).