Well personally, I think that the plastic manufacturing will be a big problem in the environment, because plastic is non-biodegradable. We already reached the limit of plastic the world can hold in August of 2017.
Since plastics aren't able to disintegrate, I'm sure many plants, animals, and humans will die because they've eaten plastic particles. 90 percent of our water has plastic in it, even if it's "filtered", and even if you can't see it. As I said before, plastic is biodegradable, which means it doesn't compost, but slowly breaks into smaller and smaller pieces.
Hope this helps!:)