14 ≥ www.georgianbay.ca GBA UPDATE Fall 2018 ENVIRONMENT Microplastics Threaten Our Water Quality, Drinking Water and… Beer? T here is an unwelcome link between your clothes and your nice cool beer. Almost 80% of clothing manufactured today is estimated to contain artificial fibres such as polyester, nylon, Spandex™ and others. When these fibres are shed from clothing into our water through washing or direct contact like swimming, they don’t biodegrade like natural fibre but begin to slowly accumulate in our aquatic environment. Other sources of microplastics in our water include degrading nylon or polypropylene boat lines, fishing nets, plastic tarps, dock materials, plastic bags, single use plastic utensils, contact lenses and construction materials. According to Lisa Erdle of the University of Toronto’s Rochman Lab, “The influx of plastic into the Great Lakes likely began over half a century ago, when industrial plastic production took off. Now, showing no signs of slowing down, annual plastic production has reached around 300 million metric tons after having doubled in the last 15 years. It is estimated that 60% of all plastics ever produced have either been diverted to landfills or have accumulated in the environment. Much of this plastic garbage is in the form of microplastics – particles derived from plastic debris breaking down into small fragments or entering the environment as microscopic particles.” Where will all the microplastics go? In a lake, they will end up near our shores or sinking, unlike the large floating ocean garbage patches. According to an article by professors from the Rochester Institute of Technology (RIT), computational modelling shows temporary accumulations forming but not persisting in the Great Lakes, instead ending up close to shore. (They noted that volunteers collected 16 tons of plastic from beaches with the Alliance for the Great Lakes in 2017.) Plastic can float or sink. While RIT’s model does not model sinking currently, they point out other studies that indicate high concentrations of plastic in sediment samples from the bottom of the Great Lakes. By David Sweetnam, Executive Director, Georgian Bay Forever, with contributions from Lisa Erdle and Heather Sargeant Rows of microplastics Rochman Lab students picked from samples. While most are impossible to see with the naked eye, each petri dish holds hundreds of these microscopic particles. Photo by Lisa Erdle. Plastic accumulation close to shores is bad news since this is where a great deal of our drinking water is sourced and wildlife biodiversity is located. As more is learned about processes that affect plastic transport in water bodies, our ability to identify plastic accumulation that could impact areas of high biodiversity will improve. 1 In Georgian Bay, high biodiversity areas can be catalogued if GBF’s aquatic biodiversity project in partnership with the University of Guelph receives the required funding.