Earlier quoted context omitted.
In this case PCP = post consumer plastic. Think micro plastic particles from ocean debris and trash washed off short.
And particularly worrisome are the little plastic beads that make your ex-foliating shower scrub so pretty looking. They're also made of plastic, and all of it goes down the sewer. In insane quantities. https://en.wikipedia.org/wiki/Microbead https://en.wikipedia.org/wiki/Plastic_particle_water_polluti...
Fwiw those are in the process of being phased out in the U.S. (as the Wikipedia article notes). A ban on their use in rinse-off cosmetics (shampoos, toothpaste, body washes, etc.) was passed in December 2015. But the phase-out lasts through 2019. The unusually short and readable bill is here: https://www.congress.gov/bill/114th-congress/house-bill/1321...