What microplastics are doing to seabirds could tell us about their effect on humans

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This week:

• What microplastics are doing to seabirds could tell us about their effect on humans
• Protesting against private jets
• How to keep your pet safe from wildfire smoke

What microplastics are doing to seabirds could tell us about their effect on humans

Some researchers estimate that humans ingest tens of thousands of microplastic particles every year by breathing in indoor air and drinking out of plastic containers. (That works out to around five grams every week, about the same weight as a handful of thumbtacks.)

These plastic fragments are showing up in digestive systems, blood, breast milk, possibly even the brain.

So what are all those tiny plastic bits actually doing to our health? Scientists still aren't sure, although a new study on seabirds, led by a team of international scientists, raises some questions about potential ripple effects on the gut that could apply to humans, too.

The researchers found evidence that microplastics may have altered the gut microbiomes of two wild bird species — the northern fulmar, found in Canada's North, and the Cory's shearwater, found around Portugal. 

The plastic fragments were linked to an increased presence of infectious pathogens and antibiotic-resistant microbes, plus a lower presence of beneficial bacteria found in the intestines that can help protect against infections.

The complex relationship between a microbiome and its host is "essential to host nutrition, physiology, immune function, development and even behaviour, and many diseases have been associated with altered gut microbiomes," the team wrote in their paper, published recently in the journal Nature Ecology & Evolution.

The researchers didn't directly measure the birds' health, but lead author Gloria Fackelmann, from the University of Trento in Italy, said their study is a "first step" toward answering questions around the health impacts of ingesting microplastics in the real world.

"The implications are far-reaching: for one, humans are also exposed to micro- (and nano-) plastics, raising the question of how humans and their (gut) health might be affected by plastic ingestion," her study team wrote.

What makes the study unique is that "we chose two wildlife species because we wanted to get a better picture of how microplastics may be interacting with the microbiomes in wild animals," said Fackelmann. "The seabirds here, they ingested these microplastics as part of their daily lives." 

Dr. Andrew Morris, a professor of medicine at the University of Toronto and the medical director of the Sinai Health-University Health Network Antimicrobial Stewardship Program, stressed that the study wasn't definitive, with much more research needed to understand the links between microplastics and microbiomes. 

The birds being studied were also likely being exposed to chemicals and other factors that could also impact their microbiome, he said.

Still, the scientists' discovery of antibiotic-resistant microbes within the birds' digestive systems is a concerning development, he said, and just one example of how the growing problem of drug resistance could have dire consequences on global health. 

The ongoing adaptation and evolution of harmful bacteria could leave humanity with fewer options to treat serious infections, making antimicrobial resistance a "huge threat" to health care, Morris added. 

Fackelmann said the next research steps include studying the mechanisms behind how microplastics are capable of causing changes in the gut microbiome, and what that means for overall health — for birds and humans alike.

— Lauren Pelley

Reader feedback

Peter Currier:

"Adam Beauchemin's piece on the impending demand crunch for EV battery minerals is a good niche view of the type and number of vehicles that should get the lion's share of them. He gives a nod to recycling used batteries, but I would have liked to have seen mention of the huge eco-degradation that mining, shipping and disposing of EV mineral waste involves."

Brian Gifford:

"I hope part of your conversation about EVs and batteries includes the crazy shift in demand for larger personal vehicles which will require larger batteries. Recent reports say 80 per cent of new vehicles sold are now SUVs and trucks. Advertising only accelerates this trend. GM is ending manufacture of one of the most affordable successful EVs, the Bolt, to focus solely on SUVs and trucks. Policy needs to change this with advertising restrictions and higher incentives for smaller cars."

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The Big Picture: Protesting private jets

When it comes to cutting carbon emissions, air travel is a notoriously stubborn problem. Full electrification is still many years away and just this week, the CEO of Boeing admitted the sheer cost of producing sustainable aviation fuel (SAF) — another highly touted solution — is a huge deterrent to getting off fossil fuels.

Decarbonizing aviation remains an ongoing challenge, but climate protesters drew attention this week to a more specific issue: private jets. On Tuesday, demonstrators hit the tarmac at Geneva Airport and blocked access to a private jet exhibition. Carrying signs with slogans like "#BanPrivateJets" and "WARNING: Private jets drown our hope," the protesters got the attention of the media and forced the airport to suspend all flights for about an hour. 

Private jets are among the most carbon-intensive modes of transport. Given its limited capacity, a private plane can generate 14 times as many emissions per passenger as a commercial plane and 50 times as much as a train, according to the European advocacy group Transport & Environment.

Hot and bothered: Provocative ideas from around the web

• In another blow to the reputation of carbon offset schemes, the CEO of Verra, the world's largest carbon offset provider, is resigning after the Washington-based non-profit approved millions of worthless offsets to major companies.

• Spring allergies are a scourge for many Canadians. Meet a citizen scientist who has been doing pollen counts since 1968.

How to keep your pet safe from wildfire smoke

Many pet owners are watching the smoky skies over Western Canada and wondering just how worried they should be about their furry companions. 

Dogs in particular need outdoor exercise, and many cats live outdoors. 

With climate change promising to make such events more common, what can you do to protect furry family members? 

The main line of defence against poor air quality is staying indoors as much as possible, according to Daniel Joffe, vice-president of medical operations at VCA Canada, a network of animal hospitals.

"​​Dogs, just like people, can have lower-airway disease, asthma-like disease, that can be triggered by the smoke and potentially, in the worst-case scenario, could end up with a very severe or fatal outcome," Joffe said. 

Joffe said brachycephalic dogs — dogs with pushed-in noses like bulldogs or pugs — are particularly at risk for respiratory tract disease. And it's a double whammy for them. Wildfires generally happen during warm weather months, when such dogs already struggle with hotter temperatures.

Other breeds are also vulnerable, especially those that like strenuous activity. Beth Barrett, a veterinarian who runs a clinic just outside Calgary, also warned that overweight dogs are more susceptible to many health problems, including those caused by smoky air.

Joffe recommends looking at the Air Quality Health Index for your area — and taking the same steps you would take for protecting humans. In Calgary last week, for example, the index reached 10+, the highest level. With such poor air, Joffe recommends letting a dog out for no more than five to 10 minutes at a time.

At an index below seven, Joffe suggested dogs could be out a little longer — 15 to 20 minutes.

"My rule of thumb is that if the smoke is starting to bother you, it's bothering your pet. And we should take them inside."

If you're looking at your high-energy husky and wondering how you could keep them indoors all day, you're not alone. 

Barrett, who also operates an indoor dog sport facility, says indoor areas like hers can provide off-leash spaces for dogs to burn off energy and get training — away from the smoke outside.

"We've sure noticed that more people are using the indoor facility right now, just because they're trying to avoid being outside when the air is so poor," said Barrett.

For those who can't get to a doggy daycare or sports facility, Barrett suggests an underrated activity for the home: training exercises. Obedience or scent-training will stimulate a dog mentally and keep them from getting bored.

"It's amazing how tired they get after a training session," Barrett said.

As for cats, Joffe has a clear message — if they're outdoor cats, this would be a good time to bring them inside.

Cody Shearer, owner of Calgary dog-walking business Pooched YYC, said he's been taking steps to keep the animals he cares for safe from the smoke. He monitors the air quality index in Calgary — when it's above an eight, he cancels walks for the day. 

Scrapping walks means less income — Shearer said he loses roughly 40 per cent of his usual revenue on days when it's especially smoky. But keeping the pets safe remains his top priority. 

"Cancelling the walks is more important than the money for us," he said.

Like Barrett suggests, Shearer finds ways to keep his animals occupied even when the air quality is poor. He runs basic training activities with his dogs to "exercise their brain instead of their bodies." 

Pet owners can hide treats around their house, set up small agility courses and work on new tricks with their pets to keep them entertained while indoors.

Masks don't really seem to be an option for dogs. That's because their face shapes make it hard for a mask to stay on. More importantly, dogs don't really know how to breathe properly through the masks.

"So it could actually make things worse," Joffe said.

— Inayat Singh

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