Arguably the most beautiful and treasured gem of our state, Lake Superior has been silently contributing to the pollution of Lake Erie, at our direct command.
By what phenomenon? Microbeads. Prized for their assumed exfoliating and cleaning power in toothpaste and facial cleanser, these tiny plastic pieces (1 millimeter or less) have become ingrained in our daily routines — although recently they have received quite the beating.
A bill was introduced in the Minnesota Legislature in February that calls for plastics to be removed from personal care products, with regulations beginning in 2017. Many states have introduced similar legislation.
So what is the cost of these small, exfoliating heroes?
The University of Auckland first outlined the consequences of plastic microbeads in a 2009 study. It found evidence of plastic microbeads flowing directly into rivers and lakes, unstoppable by water-treatment plants. Microbeads float in water and are often mistaken as tasty fish eggs by hungry fish such as perch. So now plastic from a cosmetic we use is found in the fish we eat — but what the plastic contains is even worse.
Microbeads act as a sponge for organic pollutants, so as we eat fish that have eaten microbeads, we are also ingesting chemicals such as PCBs and DDT, as found by the Ohio Department of Natural Resources' Fairport Fisheries Research Station. There's no denying it: Microbeads and their associated dangers are entering the human food chain. Furthermore, microbeads never biodegrade, so once they enter our waters, they stay and continue to wreak havoc in the ecosystem.
The scale of microbead infiltration of our natural waters is not completely known, but microbeads in the Great Lakes have been heavily studied. Lake Erie contains 90 percent of the plastic in the Great Lakes, and there are 1 million microbeads per square mile. Fish in Lake Erie have been found with microbeads in their guts. According to Beat the Microbead, an international campaign against the use of microbeads in cosmetics, 11 percent of the recorded cases of marine animal harm by marine debris were caused by microplastics.
Now to Lake Superior, which is the least polluted of the Great Lakes. Lake Erie is downstream from Lake Superior, so water from Superior eventually flows into Erie via Lake Huron. Not surprisingly, Lake Huron has intermediate levels of microbeads, while Lake Superior has low levels. However, microbeads have been found in the sediment of Lake Superior, indicating that microbeads also can sink. Those microbeads that do not sink, however, will float downstream from Lake Superior to Lake Huron.