According to a study published in theProceedings of the National Academy of Sciences, instead of the millions of tons of plastic debris the research team was expecting to find, they calculated that, at the most, only 40,000 tons are floating on the water's surface. In other words, 99 percent of the ocean's plastic is unaccounted for. As the study itself puts it, "the abundance and the distribution of plastic debris in the open ocean are still unknown."
This, however, does not mean the plastic has disappeared. Instead, scientists have discovered that at least part of it has been breaking up into smaller and smaller pieces until the plastic bits are small enough to be eaten by tiny fish. Specifically, the very same research team has found plastic in the stomachs of fish like the lantern fish, the National Geographic reports: "Because lantern fish serve as a primary food source for commercially harvested fish, including tuna and swordfish, any plastic they eat ends up in the food chain," the publication wrote. Yes, our food chain.
Other possibilities hypothesized by oceanographers include the tides washing the plastic ashore, or else it dissolving so much that it's not being detected. Organisms could be "sticking to and growing on the plastic are dragging the junk beneath the ocean’s surface, either suspending it in the water column or sinking it all the way to the sea floor" The American Association for the Advancement of Sciences wrote. "Microbes may even be eating the stuff. Best-case scenario for the fate of the missing plastic? It’s sinking from the weight of organisms sticking to it or in animal feces and getting buried on the ocean floor."
In an effort to solve this mind boggling mystery, National Geographic has teamed up with the study's researchers to map the plastic they have found already. We're guessing some of them stopped ordering sushi.