Swirling plastic pools as large as countries have long collected in our oceans, but now researchers have found that the Great Lakes face a similar problem, Discovery reports. While on a recent outing with students, environmental chemist Sherri Mason wondered whether plastic might be floating in the world’s largest freshwater system, so she and other researchers returned with a large trawl and a mesh net that traps anything larger than one third of a millimeter. They took 21 samples from Lakes Superior, Erie and Huron, which revealed that in some places there are up to 650,000 bits of plastic in a square kilometer.
“The reality is that all the plastic we see in the environment makes its way into the water, which means it’s making its way ultimately into us,” Mason told Discovery. “What we find in the lakes is coming from us, so we’re the problem but we’re also the solution.
Right now, it isn’t certain where the plastic is coming from, where it’s going or how it is being shared between the lakes and between the lakes and other waterways. While it takes hundreds of years for plastic to completely biodegrade, tiny bits chip off from plastic caps, boats, and even the microbeads in commercial face cleansers and make their way into lakes, rivers and oceans. These pieces tend to congregate where currents collide, although other bits can be found floating elsewhere as well.
Mason’s samples showed inconsistencies in concentration. Despite the high concentration in some parts of the lake, other parts only had 600 bits of plastic in a square kilometer. Either way, this means that plastic has entered the Great Lakes’ food chain. Phytoplankton, fish and humans unwittingly feed on these tiny pieces that are invisible to the naked eye, along with a cocktail of toxic chemicals. This is the first time that scientists have thought to test the Great Lakes for plastic pollution and the study is in the process of being shared with peers.
Via Discovery News
Image of Lake Superior, Shutterstock