The formation of harmful microplastics, litter all around and plastics end up going out to sea are all struggles that can slowly be fixed by using reusable or biodegradable substances.
The effect of these problems:
1) Microplastics: Plastic takes a very long time to disintegrate and when it almost does, microplastics form. These small, microscopic plastics can easily by found in the food that people eat. For instance if some microplastics end up in the ocean, they can be ingested by the fish that humans eat. This increases the risk of plastic to enter our bodies, which isn't good for our health.
2) Plastic in the sea: This effects the marine creatures living below the blue seas negatively since it could lead in them becoming extinct. When marine creatures, more specifically, turtles see a plastic bag, they have the intention that it's a jelly fish and so, they eat it, leading for them to end up choking and so, they die. Furthermore, the plastic in the sea is also a type of water pollution, making the oceans a dirty and unpleasant habitat for the sea creatures to live in. Plus, when humans see large amounts of gathered plastic floating above the sea-water, it wouldn't be such a pleasant sight, resulting in them to not want to go down for a swim and that's just a small patch. Imagine facing a whole, entire island formed by plastic materials.