Alcohol kills germs, right? That’s why they put it in mouthwash, yes? Well, Cool Mint Listerine mouthwash breaks out its ingredients list by “active ingredients” and “inactive ingredients”. Active ingredients include 0.092% eucalyptol, 0.042% methol, and a couple other things, each less than 0.1%.
But then under “inactive ingredients”, the number one ingredient is water, but the number 2 ingredient is alcohol – 21.6%. That’s over 40 proof! My vodka isn’t even that strong.
How is alcohol in 40 proof concentration not an “active ingredient” in mouthwash? Are they claiming 0.042% menthol is actively fighting germs, but 21.6% alcohol is inactively fighting it? What’s the definition of an “active ingredient” then?
Your cite doesn’t quite say that. It says 70% is better than 100%.
I’m curious why mouthwash contains any alcohol if it isn’t considered an active ingredient. Could it be keeping germs from growing in the mouthwash while it’s in the bottle?
There’s a lot of truth to this. It’s why laundry soap is blue, and why blue ketchup and clear Coca-cola tend to sell poorly. People expect certain products to look and act a certain way, because they always have. We expect ketchup to be red because tomatoes are red, and because ketchup has always *been *red. And people expect good mouthwash to burn the fuck out of their mouths.
Side note: I always dilute the hell out of my listerine with water, or buy mouthwash for kids, because I hate chemical burning my tongue in the morning.
Yes, alcohol is just added as a flavoring agent, for its biting sensation. Alcohol can, in fact, have a negative influence, because it can worsen bad breath. There have also been suggestions in the scientific literature that alcohol in mouthwash could act as a carcinogen, although there’s no consensus. A lot of mouthwashes nowadays are alcohol-free.
In order to wear dentures, I had to have multiple teeth removed; I was told to use alcohol free mouthwash for a few days. I hated the stuff; it just didn’t taste like mouthwash should taste. I believe that alcohol is used in mouthwash just because we are conditioned to expect a certain taste.
After I gave back the alcohol mouthwash in my dentist’s “bag of goodies” for about the millionith time, he ordered a stamp that proclaimed “NO ALCOHOL” in big red letters, which he stamped on the files of all alcoholic and teetotalling patients.
While the active ingredients in mouthwash may (barely) make it into solution in water, they will be freely soluble in 50% alcohol, preventing precipitation, especially in cold climates. Alcohol, when not taxed, is cheap and relatively easy to handle, and the untaxed “specially denatured alcohols” are used for many applications. SDA 37 and 38B are the commonly used SDAs for mouthwash, and SDS 38B-10 already has menthol and eucalyptol in it.
I imagine Procter & Gamble buys that stuff by the tank-car…
Anyway, while early formulations may have made a fuss about the germ-killing properties of the alcohol, I don’t know if they believed it, or if it was just a sales ploy to get people to accept the solubilizer.