While I think you're bringing up a very good point, the article says that at least in this particular study > Out of 13 lung samples, a staggering 11 contained

While I think you're bringing up a very good point, the article says that at least in this particular study > Out of 13 lung samples, a staggering 11 contained microplastics, with the most common types being pieces of PET, used to make drinks bottles; polypropylene, used for plastic packaging and pipes; and resin, often used as an adhesive or sealant.