People throw an awful lot of stuff into the oceans, and much of it washes up onto the world's shorelines. But just how much trash accumulates is shocking.
According to a new report released by the Ocean Conservancy, last year volunteers gathered 18 million pounds of garbage from beaches -- an amount that's equivalent to the weight of more than 100 Boeing 737 jetliners.
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The volunteers found a range of discarded items that included 97 television sets, 28 refrigerators, 54 bicycles and 39 toilets. But some of the finds were even more bizarre. Volunteers in Canada found a mailbox, and American beach cleaners discovered a discarded stethoscope. Jamaican volunteers found a toy drum set. Germans found a boomerang.
But most of the trash found were plastic items -- cigarette filters, beverage bottles, food wrappers and other debris, according to the report.
The plethora of plastic trash is a frightening problem, because research has shown that it's mistakenly eaten by sea birds. Already, plastic has been detected in the stomachs of 135 seabird species across the world, and researchers project that by 2050, 99 percent of all aquatic avian species will be consuming plastic.
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The seabirds most at risk are those who live at the Southern Ocean boundary in the Tasman Sea between Australia and New Zealand, the report said.
About 800,000 volunteers from nearly 100 countries participated in the cleanup. In the United States, volunteers from 34 states worked to clean up both coastal shorelines and inland waterways.
Watch: How Much Trash Is In The Ocean?