Have you heard of the Great Pacific Garbage Patch? That is a name coined to describe the vast amounts of plastic bits and other marine debris floating in the North Pacific Subtropical Gyre, one of five major ocean gyres in the world. Sadly, all the gyres seem to have their garbage patch.
Plastic stays around for hundreds of years can be a hazard to wildlife and leaches toxins into the environment. Stop using so much plastic. Buy things with less packaging, don't use disposable items and use reusable bags instead of plastic ones wherever possible.