Inuit are calling on the Canadian and Danish governments to step in and halt an international satellite launch next week, over fears the rocket's debris risks contaminating an ecological haven in the High Arctic.

On Friday, the European Space Agency and the Netherlands Space Office are launching the Sentinel-5P satellite from the Plesetsk Cosmodrome in northern Russia. Its mission is to monitor air pollution and climate change.

The rocket used to blast it into space is a converted SS-19 Cold War-era intercontinental ballistic missile — the Rokot — by German-based launch company Eurockot.

The concern for Inuit is the rocket's second stage, which contains hydrazine-based fuel and is expected to splash down in the North Water Polynya. Though it's outside of Canada and Denmark's territorial waters, it's home to a vast array of birds and marine mammals that Inuit rely on for food.

"It's the birthing ground of all the animals that we eat, that people in the North depend upon," said Eva Aariak, Canada's commissioner on the Inuit Circumpolar Council and former Nunavut premier.

"I know it's being played down in terms of the kind of effect it would have, but nobody knows. This is the most concerning part is that nobody really knows. And before people know exactly what kind of effect it can have, we will keep fighting."

It is inside both countries' "exclusive economic zones," a 370-kilometre band in which coastal countries have international recognized jurisdiction over pollution prevention.

On Friday, Nunavut Premier Peter Taptuna released a statement condemning Russia, although it's not clear what involvement the Russian government has in this launch, other than operating the launch pad and having sold the rocket to Eurockot, of which Russia is a minority partner.

Eurockot is majority-owned by France-based Astrium, with the Khrunichev State Research and Production Space Centre (whose parent company is the Russian Space Agency) owning the other 49 per cent.

When the European Space Agency designed Sentinel-5P, it went through an open procurement process and signed on with Rokot.

Fuel will burn off, space agency argues

In a statement to CBC News, the European Space Agency insisted the fuel won't reach Earth's surface.

"Please remember that under standard pressure, hydrazine boils at 113.5 C," the agency said. The stage containing the fuel will re-enter Earth's atmosphere much hotter than that, it said.

"The structural parts lose their integrity and by melting the destruction of the stage occurs. The agency said that six kilometres above the ground "the propellant components have completely burnt up."

Global Affairs Canada also said the risks are considered "very low that debris or unspent fuel" will reach the Earth's surface.

"Canada expects every effort will be made to ensure that debris does not land on Canadian soil or in Canadian territorial waters," Global Affairs spokesperson Brendan Sutton said in a statement.

Potential fuel leakage, researcher says

What triggered the outcry and responses from all sides was an article published Monday by University of British Columbia Prof. Michael Byers in Cambridge University's journal Polar Record.

In it, Byers cites scientific research out of Russia and Kazakhstan, which concludes the same fuel used in the Rokot pose "serious threats to natural ecosystems and human populations."

One study out of Russia in 1999, which Byers cites, says there may be a possibility of fuel escaping a rocket stage in aerosol form.

The fuel leakage described in the articles cited, however, didn't appear to be subjected to the same atmospheric re-entry conditions as will happen on Friday.

When questioned on whether there's an apples-to-oranges comparison, Byers agreed to an extent, before pointing to a YouTube video purportedly showing the re-entry of a Rokot second stage over Greenland in 2016.

"The video taken from Thule airbase certainly survived re-entry, and the stationary lights that one sees in the video is difficult to explain than anything other than an aerosol cloud," Byers told CBC News.

"The other thing, which I think is quite important, I don't need to prove that this fuel survives re-entry. There's no proof that it's destroyed. The burden of proof is on the actor that's taking the risky activity."

Byers said that under international law, in the absence of proof that an activity — in this case the satellite launch — wouldn't be environmentally harmful, establishing a mere risk is enough to halt the launch.

In this case, Byers said, the actor taking the risk is the European Space Agency, which he said was his focus, not Russia.

"Russia is a 'launching state' under the space-liability convention. Russia is one of the legally responsible parties. Russia, the European Space Agency, the Netherlands, and potentially, under domestic law in Germany, Eurockot as a company," Byers said.

"My focus is actually the European Space Agency. I think if this launch is going to be stopped, it will be stopped because of pressure on the European Space Agency and the Dutch government. These are actors that generally work hard to do the right thing environmentally."​

'No ecological damage,' Russian Embassy says

This isn't the first time concerns like this have been raised by Byers and Inuit, nor is it the first time space debris has been dumped into the North Water Polynya.

In response to Byers's article, the Russian Embassy in Canada called his present and past claims "emotionally charged and alarmist."

In a statement, the embassy said that in previous launches, there was no damage to the environment.

"No ecological or any other damage happened and the territory of Canada or its waters were not affected," the embassy wrote, in reference to a June 2016 Rokot launch that raised similar concerns from Byers and Inuit.

"Space experts, including from the European Space Agency, agree that the disposed second stage of the rocket and its fuel are completely burnt out."

But Byers said it's impossible to know that.

"Nobody has actually monitored the North Water Polynya for possible effects of [this rocket fuel]. So they can't say that. Nobody has actually done any environmental assessment post-launch to determine whether any damage was caused," he said.

"They have their experts, and I have a peer-reviewed article in a top Cambridge University Press journal. So this is not my opinion. I've been through the most rigorous peer review in 25 years of being an academic. This has the full weight of Cambridge University Press behind it."

In his article, Byers called for the European Space Agency to stop launching rockets using hydrazine-based fuel in favour of more environmentally friendly ones, and for environmental tests to be done in the North Water Polynya after future launches.