Back in the day, cotton farmers had access to Timik, a potent organophosphate poison that was deadly on 'yotes, hogs, gators, buzzards, etc. It caused critters to foam at the mouth and choke on their secretions. The antidote is atropine, which dries up the secretions. Timik is now hard to get, is a controlled substance.
I don't think nitrite hangs around in the tissue. It affects the hog's blood, making methemaglobin which the hog can't metabolize very well. Their organs smother becaue hemaglobin in replaced by methemagloving, oxygen starving tissues and they die. Other critters aren't as sensitive to nitrites as hogs.
Nitrites, ironically, are used in curing bacon. Ingested by a hog, nitrites will "cure their bacon" before their bacon gets cured...
DF
