I stopped worrying about it some time ago. Read this the other day, I am not worried.
"The dose makes the poison"
Fermcap-S Safe level is 13g/day, at 2 drops per carboy the per glass rate you would get is 0.009g/glass. I can't drink that much beer! 1400 pints day.
Source the "Homebrew Toxicology" presentation by Paul Hanlon, NHC 2015.
Alcohol is the most toxic thing we are ingesting.
Agreed, but why not limit what you can? I've had no trouble living with drastically reduced of Fermcap.
I would likely have to stop brewing without Fermcap. I boil 4 gallons (with the lid on until I get up to a rolling boil) in a 5 gallon pot on my stove. If I boiled over with any great frequency the wife would cut me off.
I realize that you are not trying to tell anyone to stop using Fermcap. I'm not trying to force it down anyone's throats myself. But as a pharmacist I will say that there is no medical or toxicological reason to limit your use or exposure to Fermcap. The stuff is perfectly safe and nontoxic even if used at much higher levels than as described on the label. And you are likely already exposed to this stuff on a frequent basis from other food/cosmetic products already.
Again, I understand your sentiment, but the phrase "why not limit what you can?" implies that there is a reason to limit Fermcap exposure, and there is no good reason outside of "personal choice". There is more reason to limit beer altogether than Fermcap, at least from a medical/toxicological viewpoint.