<P> The Great Pacific garbage patch has one of the highest levels known of plastic particulate suspended in the upper water column . As a result, it is one of several oceanic regions where researchers have studied the effects and impact of plastic photodegradation in the neustonic layer of water . Unlike organic debris, which biodegrades, the photodegraded plastic disintegrates into ever smaller pieces while remaining a polymer . This process continues down to the molecular level . As the plastic flotsam photodegrades into smaller and smaller pieces, it concentrates in the upper water column . As it disintegrates, the plastic ultimately becomes small enough to be ingested by aquatic organisms that reside near the ocean's surface . In this way, plastic may become concentrated in neuston, thereby entering the food chain . </P> <P> Some plastics decompose within a year of entering the water, leaching potentially toxic chemicals such as bisphenol A, PCBs, and derivatives of polystyrene . </P> <P> The process of disintegration means that the plastic particulate in much of the affected region is too small to be seen . In a 2001 study, researchers (including Charles Moore) found concentrations of plastic particles at 334,721 pieces per km with a mean mass of 5,114 grams (11.27 lbs) per km, in the neuston . Assuming each particle of plastic averaged 5 mm × 5 mm × 1 mm, this would amount to only 8 m per km due to small particulates . Nonetheless, this represents a high amount with respect to the overall ecology of the neuston . In many of the sampled areas, the overall concentration of plastics was seven times greater than the concentration of zooplankton . Samples collected at deeper points in the water column found much lower concentrations of plastic particles (primarily monofilament fishing line pieces). </P> <P> Some of these long - lasting plastics end up in the stomachs of marine animals, and their young, including sea turtles and the black - footed albatross . Midway Atoll receives substantial amounts of marine debris from the patch . Of the 1.5 million Laysan albatrosses that inhabit Midway, nearly all are likely to have plastic in their digestive system . Approximately one - third of their chicks die, and many of those deaths are due to being fed plastic by their parents . Twenty tons of plastic debris washes up on Midway every year with five tons of that debris being fed to albatross chicks . </P>

Where does all the garbage in the great pacific garbage patch come from