World - Plankton Are Making Ocean Plastic Pollution Even More of a Mess
Microbes tear up plastic into teeny tiny pieces that are even more dangerous to ecosystems
Tiny creatures are gnawing away at plastic we humans are pouring into the environment, making the pollution less visible but potentially more problematic than ever, according to new research.
In that work, published on November 9 in Nature Nanotechnology, scientists fed small pieces of fluorescent plastic to plankton called rotifers and watched to see what happened. Their observations and analysis suggest that in just a single day, one of these tiny animals in a plastic-rich environment can produce more than 300,000 particles of nanoplastic that are smaller than one micron across—a fraction of the size of a human red blood cell.
Nanoplastic is a major concern within the larger problem of microplastics, which cover a wide range of sizes, from one micron to five millimeters. Nanoplastics’ even smaller size could make them particularly harmful to humans and the environment because they can more readily get into the bloodstream and deep into the lungs. They can also be ingested by small animals and become concentrated up the food chain. The new study—which complements a growing body of research showing that plastic pollutionextends from the deepest ocean trenches into the atmosphere—sheds light on how astoundingly quickly plastic can proliferate.
“We know that microplastics eventually become nanoplastics, but you don’t think it’s going to happen that fast,” says Jacqueline Padilla-Gamiño, a marine biologist at the University of Washington, who was not involved in the new research. Other natural forces, most notably sunlight, also break plastic into progressively smaller pieces but act more slowly.
The scientists behind the new research were inspired by a 2018 study that showed that Antarctic krill could break microplastics into nanoplastics. Those animals live in extremely cold—and less polluted—environments, however. The researchers behind the new work wanted to understand whether the same phenomenon also played out in animals that lived in warmer, more plastic-filled waters, says study co-author Baoshan Xing, an environmental and soil scientist at the University of Massachusetts Amherst.