The potential negative effects of microplastics on humans and the environment has been the subject of research for some time now. However, a group of researchers led by the University of Massachusetts Amherst has found a new wrinkle to the microplastic problem. According to research reported in Nature Nanotechnology, tiny organisms called rotifers are capable of chewing up microplastics and spitting out even smaller nanoplastics at an alarming rate.
There’s a lot of plastic debris in the ocean and plastic pieces less than five millimeters long are known as microplastics. These microplastics can originate from small plastic waste (such as the microbeads often included in exfoliants) as well as larger pieces of plastic that have broken down over time. So far, we don’t know the full effects of microplastic on the environment, or what effect these plastics have on humans. However, their prevalence has many concerned.
The authors of the study were curious about how these microplastics break down into even smaller particles, called nanoplastics. More specifically, they wanted to find out what role living organisms played into the production of nanoplastics. To do so, they studied rotifers, a kind of microscopic zooplankton common in both fresh and ocean water around the world. What the researchers found is that rotifers could ingest microplastics of up to 10 micrometers in size, rapidly grind them down into smaller particles and release them back into the environment. Furthermore, the paper states that the data collected “suggest the ubiquitous occurrence of microplastic fragmentation by different rotifer species in natural aquatic environments of both primary and secondary microplastics of various polymer compositions.”
“This is a newly discovered route to produce and generate nanoplastics in both freshwater and seawater systems worldwide, in addition to well-known physical and photochemical fragmentations,” Jian Zhao, professor of environmental science and engineering at the Ocean University of China and the paper’s lead author, told the University of Massachussetts. “This finding is helpful for accurately evaluating the global flux of nanoplastics. In addition, it is known that nanoplastics can not only be potentially toxic to various organisms, they can also serve as carriers for other contaminants in the environment. Furthermore, the release of chemical additives in the plastic can be enhanced during and after the fragmentation.”