Jonathan Verreault knows from experience just how connected the Arctic is to the rest of the planet. The biologist, who is Canada Research Chair in Comparative Avian Toxicology at the Université du Québec in Montreal, has found chemical fire retardants, manufactured mostly in China, in the tissues of seabirds on Baffin Island, Nunavut.

Flame retardants, which reduce the risk of house and building fires, have been added to textiles, upholstered furniture and other products across North America since a 1975 California regulation. For more than 30 years — until they were discovered to be toxic and accumulate in body tissues — the most common flame retardants were PBDEs (polybrominated diphenyl ethers). They have been banned in Canada since 2006.

Traces of PBDEs, which do not break down easily, have found their way into environments around the globe. After they were banned, other — also potentially harmful — substances replaced them. “We knew that PBDEs were widespread in the south and were also found in the Arctic,” says Verreault. “We wanted to find out whether emerging flame retardants of environmental concern are also present in the Arctic — and if so, to what degree they are accumulating in seabirds at the top of the marine food chain.”

Verreault and his colleagues, funded by the Northern Contaminants Program of Aboriginal and Northern Affairs Canada, chose glaucous gulls near the Nunavut community of Cape Dorset for their research. “The glaucous gull is a good bioindicator species to study because it’s a top marine predator,” explains Verreault. “Any organic contaminants in its prey will pass into the gull’s body and accumulate there, occasionally at high levels. Also, these gulls are numerous in Cape Dorset and they nest on islands, which means they’re generally accessible.” Verreault’s team collaborated with the local Hunters and Trappers Association, which recruited two hunters to work with the project: “They were our eyes in the field — experts on the habitat, with its multiple islands, and on safe travel in changing ice conditions.”

When he examined the birds back in his Montreal laboratory, Verreault was not surprised to find high levels of the banned PBDEs in their tissues, as the chemicals are found everywhere. But he was not expecting to discover that the gulls’ bodies also contained the less common flame retardants now replacing PBDEs in many consumer products. “The ball is rolling on these replacement compounds,” he says. “We’re seeing them in the Arctic. The amounts are not high, but we found them in all the birds.”

How do these chemicals end up so far from where they originate? Most are carried by winds and ocean currents. But there may also be local hotspots, such as open landfills in northern communities, where gulls can be exposed to them while grabbing an easy meal.

Verreault is now looking at gulls in the Montreal area to find out how the substances change the way their bodies function. Evidence so far suggests a possible link between PBDE exposure and lower bone density.

There are signs that the situation may improve. Manufacturers dislike flame retardants because they’re expensive and complicated to use; and, thanks to public pressure, California has modified its standard. As a result, the use of flame retardants will likely decrease. “That’s good news,” says Verreault. “But we know these substances are present in the Arctic environment, and they’ll be there for years to come. There’s a lot of work to be done to understand their fate in these ecosystems — and more importantly, their biological effects.” He hopes to return to Cape Dorset in 2016 to continue his research.