Plastic can be recycled. Adding high quality synthetic oil into poor quality plastic can completely restore it's potential for use. HOWEVER! The main and mind consuming problem with plastic: plants can't grow in microplatics. Test it out, grind up plastic, put it in a bowl, and plant a seed in it, use growth hormones, use plant food, use whatever you like. The plant will sprout and die shortly after. It will never flower. Meaning once the Earths soil becomes statistically enough microplastic particles, crops won't grow, any new plants in nature will never reach maturity. Complete decaying death of the natural world because a purified compound that is incompatible with life, has been ground up and spread all over the globe. That's the fear of microplastics. That and the long term impact on people that get exposed to high enough concentrations that plants can't grow... Likely dehydrate to death as the body won't be able to absorb micro plastic laden water. You can also test that at home, but I do not recommend drinking micro plastic heavy water to see what it might be like for your grand kids.