There is an island in the middle of the Pacific Ocean, just between Hawaii and California. But no beaches, natural uncontaminated landscapes or astonishing panoramas: it is the Great Pacific Garbage Patch, the largest of the five offshore plastic accumulation zones in the world’s oceans. This floating mass of debris, mainly plastics, is formed by the enormous amount of litter that each day ends up in oceans, seas, and other large bodies of water. The numbers are shocking: according to most recent estimations, from 1.15 to 2.41 million tonnes of plastic are entering the ocean each year. And since most of plastic materials are very  resistant and less dense of water, they persist at the sea surface, transported by the currents and finally accumulating in the patch. Once these plastics enter the gyre (the circular ocean currents formed by the Earth’s wind patterns and the forces created by the rotation of the planet) they are unlikely to leave the area. So you have your Plastic Island. Which covers a surface of 1.6 million square kilometers, an area twice the size of Texas or three times the size of France.
The estimated mass of the plastic in the Great Pacific Garbage Patch is approximately 80,000 tonnes , for a total of 1.8 trillion floating plastic pieces.
The vast majority of the debris retrieved were made of polyethylene (PE) or polypropylene (PP), or derelict fishing gear. Since these materials are not biodegradable, the exposure to sun, waves, marine life and temperature changes break them down into smaller pieces, the microplastics, which are less than 5 mm in diameter. Recently the presence and the effects of microplastics have drawn great attention among scientists, researchers and organizations because of the high and not fully understood environmental impact of these materials. The main concern regards the biological integration into marine organisms and the consequent bioaccumulation: chemicals in plastics will enter the body of the animal feeding on the plastic, and as the feeder becomes prey, the chemicals will pass to the predator – making their way up the food web that includes humans. It is terrible, but probably you have already eaten a delicious plastic-tuna or a tasty microplastic-swordfish.

For more info: https://www.theoceancleanup.com/great-pacific-garbage-patch/