Will I die if I eat "methyl blue?" (Or will my pee turn blue?)
I can remember guzzling food coloring to get the effect, but then I found this.
My question is: Will Methyl Blue give the same effect as Methylene Blue? The MSDS says that methyl blue "may be harmful if swallowed," but that pretty much goes for anything. Wikipedia makes a point to say that "Methyl blue should not be confused with methyl violet or methylene blue, two other stains," and so I know that they are different. How much different is the question here.
Btw, methyl blue is available at your neighborhood pet store in the aquarium section as brown, granular crystals.