If you’re like many British Columbians and enjoy the province’s delicious and bountiful seafood, especially mollusks such as mussels, there is a good chance you’ve ingested microplastics. Recent research by TRU marine biology professor Louis Gosselin and his students has found that the majority of mussels off B.C.’s coast have microplastic particles in them. To one of Gosselin’s students in particular, Mae Frank, such findings are quite shocking.
“You hear about these things and you’re like, ‘Oh, it’s bad’ and you think of the big things like sea turtles or whales with stomachs full of plastic,” she said. “But since seeing that plastics are at the bottom of the food chain and also in things that I normally eat, and it is more sustainable to eat unlike red meat, it was kind of shocking to me.
While the knowledge of microplastics isn’t new, their existence has been known for at least twenty years, much of the research on plastics in our oceans has had to do with macroplastics, Gosselin went on to say.
“Everything bigger than about 5 mm in size is called a macroplastic and everything smaller than 5 mm in size is what we call microplastics. So at the high end of microplastics, if you had them in the palm of your hand you could see them, but then they go right down to nanometers,” Gosselin said. “The reason that we break it down and don’t call it all plastics, microplastics it’s not just a matter of seeing it, when you get to those small sizes they’re a size that small animals can swallow and ingest quite easily.”
Though Gosselin still isn’t quite sure whether microplastics are actually having a detrimental effect on marine life and the ocean ecosystem, he maintains that filter feeders such as mussels and other mollusks are the animals most affected by microplastics.
“There are a lot of animals in the ocean that we call filter feeders, they are not predators that chase big prey or eat kelp or algae. They filter water through little filters and capture microscopic particles and they ingest those. Mostly what they feed off are little microscopic algae and little animals we call plankton. Those microplastics are in the same size range as those,” he said. “We don’t really have a solid handle on whether or not these plastics are actually causing damage. We’re not even at that part. We know for sure that these animals have plastics in their bodies.”
So how exactly do these microplastics get into our oceans, rivers and other waterways? Though they are now banned in many countries, including Canada, microbeads in toiletries such as bath and body products, skin cleansers and toothpaste were previously a large contributor.
Another cause is the eventual “breaking down” of large plastic items through wear-and-tear and UV radiation. As plastics are exposed to light and air, and rub up against each other, they get brittle and break into continually smaller pieces.
Yet perhaps the most surprising contributor to microplastics in our oceans is the fabric industry.
“More and more of your clothes are made up of plastic fibres,” Gosselin said. “If you ever buy a fleece or something with microfibres, it could be clothing, it could be linen for your bed. Most of our clothing, even cotton clothing very often has it, even some portion of polyesters.”
When you put your clothing in the wash, these plastic fibres naturally wear off and make their way into the sewer system, then rivers and eventually the ocean. Though we have only known about microplastics for the past twenty years, we have been producing them much longer. As such, they can now be found in the most remote parts of the world.
“We have been doing this for long enough that by the time people realized that there are microplastics everywhere in the world,” Gosselin said. “Places that don’t produce any microplastics at all have them there. They are pretty much everywhere and they are the right size that these little animals can filter them out and consume them.”
Though Gosselin still isn’t sure whether these particles could be damaging, he does have a few theories on the problems that they could potentially present.
“They two ways they could cause problems is one, physical: where they damage the gut or tissues, or they just block the gut and don’t get digested. Another possibility is that these plastics tend to absorb chemicals,” he said.
Yet microplastics in our oceans aren’t the only problem. During fieldwork on Vancouver Island, Frank found that some of their samples had been contaminated by microplastics in the air.
“[It] would be an interesting thing to go forward with, looking at them in the air, because we are definitely breathing them in anytime we wear any type of synthetic clothing,” she said. “It is all over our bodies, it’s in our lungs. It has also helped me to think more and be more conscious of what I’m wearing.”
So what exactly can be done to mitigate the number of microplastics headed to our oceans? While Gosselin believes better government regulations are key to reducing microplastics, that isn’t the only option.
“One of the things we could do is change our municipal filtering systems to take account for those,” he said. “The other one is perhaps to approach the clothing industry. Those are the key to making changes, we have made so many changes over the years to different aspects when we’ve realized pollutants were a problem.”