Plastic in the oceans now ranks as one of the biggest threats facing our planet.
Plastic does not biodegrade on any practical time scale. Instead plastic photodegrades, breaking down to smaller and smaller pieces, all of which are still plastic polymers.
“Except for a small amount that’s been incinerated, every bit of plastic manufactured in the world for the last 50 years or so still remains. It’s somewhere in the environment.” Anthony Andrady, senior research scientist
The extent and impacts of plastic debris in the oceans are covered in the presentation:
All PDFs of the Oceans PowerPoint presentations are available under “Educational Material”.