Cosmic boys and girls

What is a plastic. This sounds like an easy question, but in practice it is a lot more complicated. And yet another one: which plastics other than the most common PE are in cosmetic products? Or, what do we put on our bodies and do we flush away when we shower?

Ban the Bead is lobbying for a ban on plastic in cosmetics. If this ban would become reality, which substances are we talking about and what would be the impact?