Researchers race to find the source of microplastics choking the world’s oceans
Groundbreaking research into one of the world’s most complex pollution problems is underway at B.C. labs
Scientists are growing increasingly concerned about microplastics in water and in the food chain, but they face some daunting challenges in the race to uncover the sources of the problem.
“We’re encountering a pollutant unlike any pollutant we’ve ever seen before,” says Dr. Peter Ross, director of ocean pollution research at the Vancouver Aquarium. “This is not a chemical pollutant, it’s a structural pollutant.”
Recent samples his team have taken off the B.C. coast contained up to 25,000 plastic particles and fibres in just one cubic metre of water.
Yes, some of it comes from plastic bags, foam packaging, cigarette butts and other remnants of the millions of tonnes of plastic debris slowly breaking down in the world’s oceans.
But there are some surprising sources, too, like laundry.
“A single sweater could release as much as 10,000 particles of microplastic fibres,” said Ross.
“That’s getting into the wastewater stream, and you have a million or two million people doing such laundry — it adds up.”
Sewage treatment plants may hold answers
But no one knows yet how washing your favourite fleece jacket fits into the bigger picture.
To find out, Ross is working with sewage treatment plants to measure the number and types of fibres in the water coming in, and later sampling the treated water as it flows out into the Fraser River to compare.
What they find could lead to changes in filtering techniques at treatment plants.
Water sampling is also being done out in the open ocean, revealing a mix of fibres and other microplastics, defined as anything smaller than five millimetres in size.
It’s a global issue, so everyone has an interest in reducing the amount of plastic being added to the world’s waterways. One estimate puts it at the equivalent of a garbage truckload every minute. At this rate, by 2050 there will be more plastic in the ocean than fish.
To home in on the problem, technicians at the Vancouver Aquarium lab recently began using a $325,000 infrared spectrometer like the kind usually found in crime labs.
It can identify the type of plastic from tiny samples.
‘It’s not going to give us the exact fingerprint,” says Ross. “It won’t say ‘Walmart fleece made in China,’ but it will confirm it is plastic, give us the category, tell us about additives and sometimes actually a manufacturer.”
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This water sample taken by researchers in B.C.’s Strait of Georgia contained an average of 3,200 plastic particles per cubic metre of ocean. Other samples off Vancouver contained up to 25,000 particles. (Vancouver Aquarium)
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B.C. researchers race to find the source of microplastics choking the world’s oceans
By Greg Rasmussen, CBC NEWS, March 11, 2017