Aye, this is the exact problem that early sunglasses that didn’t block UV light had. Wear ones that offer UV protection! https://www.aao.org/eye-health/tips-prevention/sun https://www.aao.org/newsroom/news-releases/detail/seven-myths-about-sunglasses-could-damage-vision
Those water flavor squirts, mio or crystal light type stuff. I’ll drink plain water over just about everything else (egg nog is the weakness and exception right now…), but the various lemonades or fruit flavors are always nice to have around. I wouldn’t be surprised if something in their composition is not good for you.
A slightly more titillating answer would be lube. You’re putting something on a mucous membrane, and it’s almost guaranteed that some will be absorbed or ingested.