I wonder about all the take out containers. Is paper/cardboard is safe? Like the ones Chipotle uses? Or are they coated with some plastic/toxin that we are not

I wonder about all the take out containers. Is paper/cardboard is safe? Like the ones Chipotle uses? Or are they coated with some plastic/toxin that we are not aware of? And the bowls for soup, they seem to be coated with something.