When I was 20 weeks pregnant, we went to a kids sale and bought a bunch of bottles. A friend of ours gave us a bunch, as well. They're all the same type of bottles. The problem is, I don't know if they're bpa free or not. I read somewhere if they have a yellow tinge to them, they are bpa free. I think about 4 of the bottles are yellowish but can that staining occur from formula, as well?

Should I just re-sell them all and buy ones I know are BPA free? I'm thinking that's the way we should go but I wanted opinions.