Plastics
The impact of plastics on aquatic systems is big news and of major concern these days.
Since 2019, researchers have been conducting experiments of increasing size to explore what happens when plastics get into our lakes.
What are microplastics, and what can we do about them?
Microplastics are tiny particles of plastic that are smaller than 5 mm.
Microplastics come from a variety of sources. While much hype has been made about the presence of microplastics in facial scrubs and cosmetic products (take a look at your scrubs or toothpaste at home—if they list polyethylene in the ingredients, those are microplastics), these sources actually make up a relatively small quantity in most regions.
How much of this stuff is out there?
In 2014, it was estimated that the ocean had approximately 270,000 tonnes of plastic floating on the surface, and we don’t really know how much has settled out. However, somewhere between 5 million and 13 million tonnes is added annually from coastal cities—a shocking number.
In a study on Lake Winnipeg, researchers at Lakehead University, the University of Manitoba, and IISD-ELA found densities of around 1 microplastic particle for every square metre of water, which was comparable to how much was found previously in Lake Erie.
At IISD-ELA, researchers found microplastics in every one of the nine lakes they tested (before they had added any themselves), while 90% of samples taken from the North American Great Lakes found unsafe levels of microplastics.
Even our groceries aren’t safe; 90 percent of the items we find in our fridges and grocery stores—from burgers and steaks to chicken and even plant-based foods—contain microplastics.
Why should we care?
For starters, plastic is a manufactured product—it does not occur naturally, so anywhere we find it in nature is directly because of us. In the case of microplastics, there are few applications where one can say it was intentionally added to ecosystems, so this represents a waste product of our current lifestyle, which relies heavily on plastic products.
Secondly, there is evidence that these particles can act as vectors of contaminants and carry harmful substances from the water column into the organisms that consume them, such as fish.
There is also increasing evidence that fish do ingest these microplastics. While this contaminant transfer has been demonstrated in the lab, a lot of work is needed to figure out the effects on fish in the wild that are exposed to the levels of plastics that we are currently observing.
What is IISD-ELA doing to tackle the problem?
Experts on plastics
Related projects
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