I like to look up stuff, even if I’m not remotely qualified to understand the results.
Tartrazine induces structural and functional aberrations and genotoxic effects in vivo
Is tartrazine really safe? In silico and ex vivo toxicological studies in human leukocytes: a question of dose
My (thin) grasp of things is that even though it’s a food additive, it’s not heavily studied, and not at higher doses, but the two studies above don’t paint a great picture. And slathering it on your skin is definitely more than you’d come into contact with than what’s needed to color food.
So, yeah - not a parlor trick I’d do to gross out my friends.
Maintaining a policy of radical annoyance, I see.