Scientists have been watching trash pile up in the world's oceans for about a half-century, when plastics came into widespread use. Since plastics don't biodegrade, or do so very slowly, the trash tends to remain in the ocean, where circling currents collect the material in several marine "garbage patches.

One of these trashy areas is said to be roughly the size of Texas. The water in these at-sea landfills is thick like a plastic soup, oceanographers told CNN.
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Plastics and cigarette butts are the most common types of ocean litter, with plastic making up about 80 percent of the ocean trash collected in some areas of the world, a U.N. news release says.