Are you giving someone bad blood in that case?

The negative health effects of PFAS are completely irrelevant if the alternative to this "bad blood" is death.

Generally agree, but that could be true of many other things like lead too. So we have to be careful not to take it to the extreme.

I can direct you to answers I got a couple weeks ago when I asked a similar question: https://news.ycombinator.com/item?id=36261100

Well, assuming they likely have some PFAS already in their system, you might just be giving them blood with the same concentration of PFAS that they already have.

Not always, as quite often the donation is on hand, but not necessarily used.

Also: better to save a life and either average down whatever PFA count they have, or bolster their blood volume so they can start producing their own lower PFA infested hemoglobin.

Lesser of evils, and kind of a win win: if everyone was blood letting for the safety and humanity of others.

If you're donating because you know your levels are elevated then I'd agree with this thought.

(While also agreeing with those in the thread saying that high-PFAS donations are likely often better than no donations)