During the deepest human sea dive ever, 35,853 feet/10,928 meters down to the bottom of the western Pacific's Mariana Trench in a one-person submarine, underwater adventurer Victor Vescovo found what may be newly discovered species of marine life along with candy wrappers and a plastic bag. This is the third plastic bag that divers have found in the Mariana Trench, considered the deepest natural trench on Earth. From National Geographic:
A study released in October 2018 documented what is still the deepest known piece of plastic—a flimsy shopping bag—found at a depth of 36,000 feet inside the Mariana Trench….
Single-use plastics are virtually everywhere, and they may take hundreds of years or more to break down once in the wild. The Mariana Trench has higher levels of overall pollution in certain regions than some of the most polluted rivers in China, according to a study in February 2017. The study's authors theorized that the chemical pollutants in the trench may have come in part from the breakdown of plastic in the water column.