Many Canadians are pledging to delete their Facebook accounts as part of an online campaign encouraging people to permanently log off the site amid mounting concerns that the social media giant is inappropriately sharing users' information beyond their circle of friends.

Privacy experts say numerous Canadians are taking to other social media platforms to join in on the .DeleteFacebook hashtag in the wake of recent revelations about the potential for their personal information to be mined for political gain.

Canadian data scientist Christopher Wylie has accused a voter-profiling company of improperly obtaining private Facebook data from some 50 million users in an effort to tip the scales in the 2016 U.S. presidential campaign and the U.K.'s Brexit referendum.

Former Ontario privacy commissioner Ann Cavoukian said a data leak of that scale was an "unthinkable proposition" for many Canadians who have long harboured frustrations about Facebook's apparent lack of safeguards to protect user data from being shared with dubious actors.

"People are very concerned and they feel they've lost control, and this just confirms that," said Cavoukian, who is an expert-in-residence at Ryerson University's Privacy by Design Centre in Toronto.

"You just reach the point where you say, 'Enough is enough. I'm out of here."'

She said the exposure of the data-harvesting technique has been a wake-up call for citizens who fear similar tactics could be used to influence Canada's 2019 federal election, and now feel compelled to stand up for their country's democratic institutions.

"No one wants to be under that kind of dark influence," Cavoukian said. "You have no idea what ... massive shifts are happening as a result of this. You're being manipulated."

University of Toronto marketing professor David Soberman said there has been increasing awareness about the risk of political operatives using social media tactics to sway elections.

Soberman said he thinks the Facebook data leak has resonated not only because it punctured public confidence in the social media company's privacy protocols, but because it had a tangible effect in the election of U.S. President Donald Trump, whose campaign has been linked to the data analytics firm allegedly behind the data-harvesting technique.

In an increasingly interconnected world, he said, what happens in one jurisdiction can signal what will happen in another, so all Canadians have to do is look to their southern neighbours to understand that social media meddling can have sweeping political consequences.

"Facebook is moving from the world of a novelty to becoming what I would almost call a public utility," he said. "Facebook provides a lot of value to a lot of people ... but when you've got a really, really valuable company and you're under threat, you've got to figure out actions you can do to protect that value."

Mike Smit, an associate professor at Dalhousie University's School of Information Management, said most people are aware of the privacy risks involved in sharing their personal information with Facebook, but their reservations are outweighed by the immediate rewards of online connection.

But as the potential loopholes in Facebook's privacy measures become harder to ignore, those seemingly abstract privacy concerns have come to feel more concrete for many social media users, Smit said.

"It changes the whole calculus (of the) decision-making process when we thought there were all these protections in place, but instead, they're not," he said. "Our safety blanket has been ripped away from us and we're feeling vulnerable."

Smit said the social media company's initial cagey response to the revelations did little to restore consumers confidence that their private information was in safe hands.

Days after the data leak was first reported by The Guardian newspaper and the New York Times, Facebook CEO Mark Zuckerberg said Wednesday that the company is taking steps to protect people's private information, including banning developers who don't comply with audits and limiting access to user data.

"We have a responsibility to protect your data, and if we can't then we don't deserve to serve you," Zuckerberg said in a statement. "I've been working to understand exactly what happened and how to make sure this doesn't happen again."

Facebook has denied the data collection was a breach because people knowingly provided their information. The company has said a University of Cambridge psychology professor accessed the information after he requested it from users who gave their consent when they chose to sign up for his test via a Facebook app.

The newspaper reports said Facebook first learned of the leak more than two years ago, but didn't disclose it until now.

-- With files from The Associated Press