Actually, I have 3 bottles of McCormick Red food coloring that list the ingredients as Red 40 and Red 3. They are a couple years old now and the current McCormick formula may have changed. Regardless, if you want to use food dye for emulsion purposes, I agree that the Neon coloring would be a better choice.
As an aside, the Red #3 food dye I got from the nice lady on eBay appears in all respects to be exactly the same as the Erythrosine B I ordered from Magancol in the UK. Have not done any emulsion test yet, which would be the real confirmation. However, my first ortho emulsion is sitting halfway done in the fridge now waiting to be noodle washed. (In other words, at this point I have not yet had a chance to try out ANY ortho emulsion just yet.)
I'm glad to see the Formulary is making the Erythrosine available. That really helps to take some of the angst out of the process for those interested in trying.