The global use of plastics has been found in our water supply and oceans with a disastrous effect on the environment. There fact that plastics do not decompose and will continue to plague the ecosystem makes the issue even more imperative for our generation to act now. Then negative impact to human and animal life due to plastics, has already been noted.
Plastic is not our greatest threat to the ecosystem, but it is still a great threat! We still have methane gas to contend with, air pollution from factories exuding waste and overfishing. In actual fact, you could say that our greatest threat to the ecosystem is a whole is us!
The greatest threat to our ecosystem is not plastic, but humans and their behavior. If we outlaw plastic, they will just invent something else just as dangerous or more maybe even more dangerous. Humans have an incredible capacity for self-destruction that probably won't be vanquished until we are all dead.
Plastic is not a big threat to our ecosystem. I believe that as more and more people recycle their plastic in different ways that it will become a non-issue. I also believe that as we learn new ways to make plastic from bio-degradable materials that we will eventually make a complete transition.