Highlights from Day Three of the Symposium: Apples to oranges? Scientists are having a hard time comparing their research findings on marine plastic

There is no standard method for analysing plastic pollution in the oceans – and no agreement on how much standardization is needed

If you look for plastic in the oceans, you will find it, and in alarming quantities. That much has become apparent during the first two days of the International Symposium on Plastics in the Arctic and Sub-Arctic Region. During day three, on Thursday, the discussion turned to the need for scientists to narrow down the ways they measure the plastic they are finding, especially microplastics.

The study of plastics in the oceans is a newish field. Plastics themselves only became widespread in the 1960s, and it wasn’t until 2004 and the publication of a paper titled “Lost at Sea: Where Is All the Plastic?” that the research wheels were set in motion.

Early on, scientists primarily used one method to study microplastics in water. The method – collecting samples, separating plastics according to their density, studying them under a microscope, analyzing them with a spectroscope, and then comparing their signatures to known values – became the gold standard. 

It is still used, but nowadays scientists also employ a number of other techniques for everything from the way they capture plastic to the way they determine what it is and then describe how much they have found. Jes Vollertsen, a professor of environmental engineering at Denmark’s Aalborg University, captured some of these techniques in the following flow chart that he shared during his symposium presentation, giving a sense of how diversified this field has become.

In part, the growth in the number of analytical methods reflects the fact that the more scientists learn about plastic in the environment, the more questions they want to ask about it.

“How you analyse for microplastics depends on what you want to get out of it,” says Vollertsen. He then rolls off a long list of things those in the field would like to know: source, size, shape, composition and far more.

With increasing interest comes increasing research, and with increasing research comes a growth in the number of publications. Last year, 2,000 papers about marine microplastics were published, and that 2004 paper was cited 80,000 times. But, with so much being discussed, and so few studies discussing the matter in the same way, the result has been not just insight but also confusion.

A 2019 paper went so far, according to Vollertsen, as to declare that most of the new research findings coming out of this exponential boom in publications could not even be compared to each other.

“This is still a major problem,” he says. “We cannot compare different studies.”

A part of this can be chalked up the field’s age; it takes time to come up with standards everyone agrees on. And when there is no consensus on standards, everyone believes their own preferred standards are best, scientists lament.

“We need to find one method that is pretty simple so that you can actually use it everywhere,” says Vegard Stürzinger, a marine biologist. “Right now, everybody is just doing what they want to do.”

Do we need more standardization – or less?

Not everyone agrees that divergent analytical methods are a problem, and even those who do suggest that the quest for harmonization can go too far. If one of the mantras of the symposium so far has been that “plastic is everywhere,” another is that “there is no one-size-fits-all approach” to studying it.

This is especially true when the talk turns to studying the effect that plastics have on marine life. The northern fulmar, a species of seabird whose intake of plastic is widely studied, may be as close as scientists come to having a standard, but it is by no means the proverbial canary in the coal mine that would tell us everything we need to know, according to Jen Provencher, a research scientist with Environment and Climate Change Canada, a federal ministry.

Indeed, rather than rushing to standardize a single technique for studying plastics, it is necessary, she believes, to let scientists take the approaches that best suit their ends.

“People want to know more,” she says. “There is no silver bullet. We need to think about all of the pieces and about what we want to know about in order to select the species or compartments” that are best suited to a study.

Compartments are parts of an ecosystem, and Provencher was involved in an effort to identify which compartments of the Arctic marine environment scientists should focus on when studying plastic litter. The group started with 11. It ended up with four: water, sediments, beaches and shorelines, and seabirds.

That decision disappointed those in the field who wanted to be given a single place to look, but narrowing it down even to two, Provencher argues, would have oversimplified a situation that we still do not fully understand.

There is, in fact, an argument to be made for looking at more parts of the picture, not fewer, according to Douglas Causey, a professor at the University of Alaska Anchorage who is affiliated with the Harvard University Belfer Center for Science and International Affairs.

In the early years of studying plastics in the Arctic, for example, most research was conducted on seabirds. Nowadays there are more papers about the effects of plastics on fish. But, Causey says, just because we are studying fish more does not mean we are studying birds less.

“We know so little about the effects of plastics in the marine environment that what is happening isn’t so much a shift from seabirds to fish as it is adding other components of the food web,” he says. There is still so much to be learned.

The symposium will resume on Monday 8 March with Day Four, when the discussion will turn to efforts to monitor plastics in the marine environment and their effects on ecosystems. The focus of the final day on Tuesday will be ways forward, with conversations about how to clean up plastics and how to prevent them from entering the environment in the first place. 

Highlights from Day Two of the symposium: Plastic microfibres illustrate the challenges of fighting marine litter

Avoiding use of plastic might seem like an obvious approach, but good luck convincing fleece lovers in cold climates

Scientists have accumulated ample evidence that plastic pollution is a dire problem in Arctic waters and along the region’s coastlines, as discussed during the first day of the International Symposium on Plastics in the Arctic and the Sub-Arctic Region. Presentations during the second day of the symposium gave a sense of how challenging it will be to address the problem.

Consider just one of many sources of marine plastic litter: your clothing.

In a lot of places, clothing is something that we, for at least part of the year, choose based on its ability to keep us warm. And, depending on your fashion sensibilities, you probably prefer that it lasts for several seasons. For the oceans, that is bad news.

That’s because most of our modern winter clothes are made from artificial fibres, essentially a form of plastic that is spun into thread and woven into cloth. These fabrics provide numerous benefits: they are lightweight, quick drying, highly insulating, and remarkably resistant to wear. But those benefits come at a cost to the natural environment.

Your typical five-kilogram load of laundry releases perhaps 6 million microfibres, tiny bits of fabric that your clothing sheds while being washed. Depending on how conscientious you are (you can buy a filter for your washing machine) or where you live (some cities remove microfibres from their wastewater), the actual number of microfibres that reach the sea varies. And laundry is not the only way for microfibres to make their way into wastewater.

If cities do take steps to remove microfibres from wastewater, it can make a dramatic difference, according to Dorte Herzke, an environmental chemist and senior researcher with the Norwegian Institute for Air Research. A recent study she conducted looking at untreated water released by the waste system in Longyearbyen, Svalbard, found that its 2,400 residents sent some 21 billion microscopic particles of plastic into the adjacent fjord each year. Comparisons are hard to come by, she says, but the city of Vancouver, Canada, with 675,000 residents, which does filter its sewerage for microplastics, was found to release 30 billion particles a year — dramatically fewer per capita. In the Arctic, it is the norm that wastewater is only treated for microbial contamination, if that.

The precise source of Svalbard’s microplastic pollution is not known, but Herzke told the symposium on Wednesday that the main suspected culprit is laundry, given the type of particles she collected and that much of the release coincided with times that people were likely to be doing the wash.

Encouraging people to use different kinds of fabrics, or treating existing fabrics differently, might help reduce microfibre pollution, but she cautions that it would be a hard sell to get the people of Longyearbyen and places like it to accept lower-performing fabrics.

“We have to remember that people in the Arctic really like their fleeces and their wool to keep them warm,” she says.

Artificial fabrics, and indeed all sorts of plastic products, do what they are supposed to do on land, but once they hit the water they become a scourge.

“The question is what do you want from a fabric,” says Lisbet Sørensen, a chemist with SINTEF, a Norwegian research outfit, who has studied how artificial fibres break down. “Do you want it to be durable, or do you want it to degrade fast once the particles get into the environment?”

(Wool-lovers don’t get off the hook entirely: The dyes and other chemicals used to turn wool into yarn and yarn into clothing are themselves types of pollutants.)

The most obvious way to keep plastic out of the water is to not use it all, reckons A.N. de Vries, a resource-management specialist with the University Centre of the Westfjords. “But that’s not possible, because we are still going to need it in so many ways,” she says.  

Instead, de Vries suggests addressing plastic pollution at the points where it enters natural environments. Rivers, which are big contributors to plastic marine litter because they can transport large amounts of waste of all sizes over long distances, should get particular attention, she believes.

Another approach, recommends Georg Hanke, a scientific officer with the European Commission, is for scientists to make sure that lawmakers know when a situation requires their attention, and what the costs of doing something (or not doing something) will be.

The EU already employs what he calls “triggers for action.” These, he explains, are things like threshold values that indicate when scientists believe political attention is warranted. One of the EU’s triggers, for example, is a limit of 20 pieces of litter on a 100-metre stretch of coastline. Arctic countries, he says, ought to consider setting their own limits.

“Policy needs evidence,” Hanke says. “Whatever the measure, there will be some costs, so policymakers need to be sure it is the right thing to do.”

Highlights from Day One of the symposium: Plastic, plastic everywhere

Plastic is piling up in the Arctic. Scientists are just starting to get a handle on what that means.

Marine plastic pollution is fouling the Arctic as well as posing a broader planetary crisis. But scientists still have much to learn about the problem, which a senior United Nations official on Tuesday ranked as a top global concern alongside climate degradation.

“Carried by the currents, waves, and wind, plastic pollution is found on Arctic beaches, in the water column, in the sea ice, in the sediments, in Arctic birds, in mammals,” said Inger Andersen, executive director of the UN Environmental Programme.

Andersen’s comments came during the opening session of the International Symposium on Plastics in the Arctic and the Sub-Arctic Region, organized as part of the Icelandic Chairmanship of the Arctic Council.

The symposium was originally scheduled to be held in 2020 but was postponed and then moved online due to the COVID-19 pandemic. In the meantime, the need to address ocean litter did not disappear, according to Andersen. Indeed, the problem, she said, has become even more urgent as vast amounts of face masks, plastic gloves, single-use food packaging, and other throwaway symbols of the pandemic have found their way into the oceans.

“We are not going to make them the enemy, we need them for COVID-19,” she said. “But this plastic waste stream threatens to negate strides that have been made in the public awareness around plastics and the fight against disposable items.”

There is no precise figure for how much marine plastic litter there is; the simple vastness of the oceans makes it impossible to know for certain, as does the wide variety of sizes, types, and locations of plastic debris. Scientists’ best estimate, however, is that there are probably 150 million tons floating around, ranging in size from giant fishing nets to microplastics, tiny fragments of once-larger items. Another 8 million tons are added each year. How much is in the Arctic is unknown, but one recent study found plastic particles in all but one of 97 seawater samples, and sea ice is known to contain extremely high levels of microplastics.

“Plastic litter can be found literally everywhere in our environment, with most of it ending up in our oceans,” Guðlaugur Þór Þórðarson, the Icelandic foreign minister, said. “We cannot continue down this road any longer.”

Focusing leaders’ attention on the plastic crisis

Iceland has made addressing plastic pollution one of the priorities of its two-year Arctic Council chairmanship, which draws to a close in May. At that time, representatives of the eight Arctic countries are expected to agree on standards that will form the basis of improved scientific study of plastics in the region. Þórðarson underscored that research is needed to identify how plastics are reaching the region’s waters.

“Knowing the extent of the problem will bring us closer to developing responses,” he said.

Although it is not possible to determine the origin of much of the plastic that ends up in the Arctic, studies of what can be identified suggest that only some of it entered the water from the Arctic. Often, scientists say, it is transported from other oceans, or, studies suggest, it is deposited there by rivers, many of which pass through urban or industrial areas.

“Plastic waste flows from rivers to the oceans; it has no problems crossing borders,” Krista Mikkonen, the Finnish environment minister, said.

This, she explained, is why the countries of the Nordic Council, which Finland currently heads, are pushing for the UN to agree on a measure that will prevent plastic pollution.

“The world is experiencing a traumatic challenge combatting plastic pollution in the environment,” she said. “Plastic pollution is global problem that requires a strong global response.”

“It’s ubiquitous”

Scientists participating in the first day of the symposium repeatedly expressed surprise at the amount of plastic that studies were revealing. “Basically, it’s ubiquitous,” said Melanie Bergmann, a marine ecologist and senior scientist with Germany’s Alfred Wegener Institute for Polar and Marine Research.

But even as progress has been made identifying the geographic origin of much plastic litter, and, in some cases, which type of activity it stems from, scientists are only starting to understand what growing amounts of plastic litter mean for wildlife, and, ultimately, humans.

In some cases, the effects of plastic are obvious, if disturbing. One of the pictures the symposium is featuring shows a seal with a deep scar around its neck. The injury suggests that it swam into a piece of discarded fishing net as a pup. Unable to free itself, the net gradually tightened as the seal grew, cutting into its flesh. If that is indeed what happened, the seal was lucky it escaped with only a scar; getting stuck in a net can doom a seal to death by gradual strangulation over the course of several years.

Less obvious is the effect on animals that consume plastic. Studies have shown that 70 per cent of northern fulmars, a type of seabird that is common in the Arctic, have plastic in their systems. Samples of their waste indicate that the plastic they consume is not excreted.

“We know plastic is being ingested by lots of Arctic animals, but we know very little about how it is affecting the ecosystem,” said Eivind Farmen of the Norwegian Environment Agency.

Pollution prevention is key

So far, removing plastic pollution is largely limited to occasional beach clean-ups of larger items. Some work is being done to figure out how to remove microplastics from sediment, but, for now, there is little that can be done about it.

Instead, the best use of the few resources that are available for addressing plastic litter would be to prevent it from getting into the water in the first place, reckons Kine Martinussen of Keep Norway Beautiful, a conservancy.

One way to do this, she said, is to take up the matter directly with the fishing industry and owners of commercial vessels, both of which account for large amounts of plastic litter.

“We have a long list of the items of that we find. We have a sort of OK understanding of how they travel,” she said. “But we don’t know what’s happening at the littering moment, or how we can alter the routines and make sure that it doesn’t happen.”

Another thing to do: remind ourselves that, like it or not, we are all litterbugs.

“The media in Norway will sensationalize the find of a bottle from Great Britain on our shores. And that will be in the public imagination for a while,” said Martinussen. “But in Britain they will have the same article, only it was a Norwegian item.”