Volunteers in orange life vests row through a sea of floating debris and plastic bottles while trying to clear a clog at Vacha dam near Krichim, Bulgaria.
Empty bottles will eventually fill with water and sink. The polystyrene bottle caps will float for decades.
"Manufacturers say PET is green because it's 100 percent recyclable," says the Plastic Pollution Coalition's Russo. "But nobody's able to collect 100 percent of the plastic. The problem is that these bottles are meant to be thrown away."
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