As someone who avoids cooking with plastic, I've always wondered... what makes people think it's safe? Does it not occur to most people that plastics can break down through the heat they're subjected to, or do they assume the plastics in question have been specifically designed to adequately withstand that?
Generally I assume that I consume microscopic inedible dirt/mineral/etc particles all the time without know it and they most likely pass through my digestive system. I know of course that digestion is complex and that many of these likely are absorbed to varying degrees. I try to not cook with plastic generally but I also do not go out of my way too much to avoid it - same as me not trying to eat vegetables with dirt on them but not being anal about making sure all vegetables I consume are dirt-free