Garbage patch
A garbage patch is a gyre of marine debris particles caused by the effects of ocean currents and increasing plastic pollution by human populations.
These human-caused collections of plastic and other debris are responsible for ecosystem and environmental problems that affect marine life, contaminate oceans with toxic chemicals, and contribute to greenhouse gas emissions.
Within garbage patches, the waste is not compact, and although most of it is near the surface of the ocean, it can be found up to more than 30 metres (100 ft) deep in the water.
[2] The 10 largest emitters of oceanic plastic pollution worldwide are, from the most to the least, China, Indonesia, Philippines, Vietnam, Sri Lanka, Thailand, Egypt, Malaysia, Nigeria, and Bangladesh,[3] largely through the rivers Yangtze, Indus, Yellow, Hai, Nile, Ganges, Pearl, Amur, Niger, and the Mekong, and accounting for "90 percent of all the plastic that reaches the world's oceans".
[8] Researchers collected a total of 3070 samples across the world to identify hot spots of surface level plastic pollution.
[11] Despite the common public perception of the patch existing as giant islands of floating garbage, its low density (4 particles per cubic metre (3.1/cu yd)) prevents detection by satellite imagery, or even by casual boaters or divers in the area.
This is because the patch is a widely dispersed area consisting primarily of suspended "fingernail-sized or smaller"—often microscopic—particles in the upper water column known as microplastics.
[40] The North Atlantic patch is one of several oceanic regions where researchers have studied the effects and impact of plastic photodegradation in the neustonic layer of water.
[43] Unlike organic debris, which biodegrades, plastic disintegrates into ever smaller pieces while remaining a polymer (without changing chemically).
[44] Some plastics decompose within a year of entering the water, releasing potentially toxic chemicals such as bisphenol A, PCBs and derivatives of polystyrene.
Plastic pollution affects at least 700 marine species, including sea turtles, seals, seabirds, fish, whales, and dolphins.
[53] Since as much as 70% of the trash is estimated to be on the ocean floor, and microplastics are only millimeters wide, sealife at nearly every level of the food chain is affected.
[53][58] Larger animals are also affected by plastic consumption because they feed on fish, and are indirectly consuming microplastics already trapped inside their prey.
