TORONTO -- A new study has found that some Canadian cities have higher levels of lead in their drinking water than Flint, Michigan, which has become synonymous with contaminated H20.

The year-long investigation, conducted by more than 120 journalists from nine universities and 10 media groups including The Associated Press and the Institute for Investigative Journalism at Concordia University in Montreal, reviewed thousands of previously undisclosed results and tested water from hundreds of homes in 11 different cities. Researchers recorded lead levels above national safety directives, including at some schools and daycares.

About one-third of tests exceeded the Canadian guidelines of 5 parts per billion with some of the highest levels recorded in Montreal, Regina and Prince Rupert, B.C. Prolonged exposure to high amounts of lead over months or years can result in lead poisoning, which can cause serious health effects, particularly among young children.

In Canada, there is no national mandate to test drinking water and agencies that conduct tests have no obligation to inform residents. Provinces set their own rules for water testing and lead pipe replacement. In British Columbia, where Prince Rupert recorded lead levels of 15.6 ppb, municipalities are not required to test tap water.

“There is a patchwork of testing systems across the country,” said Toronto Star investigative reporter Robert Cribb, in an interview with CTV News Channel. “Politicians have not turned their attention to this. This has not been on the public radar at all. Our attempt here is to try and renew a conversation about this.”

Canada is no stranger to crises regarding water quality -- numerous Indigenous communities across the country have endured 'boil water' or 'do not consume' advisories for years, even decades. After being elected to office in 2015, the Liberals promised that they would ensure that all long-term drinking water advisories on public systems on reserves were lifted by 2021. Since November 2015, 87 advisories have been lifted, but 57 still remain.

One of the issues discovered in the new investigation is that many jurisdictions aren’t even sure how much of their water system uses lead pipes. The investigation involved surveying cities across the country about their lead pipe networks, said Cribb. Surveys revealed that most cities only have “estimates.”

“We still have lead pipes everywhere and we don’t even seem to understand where they are,” he said.

The biggest problem, according to Patti Sonntag, director of the Institute for Investigative Journalism at Concordia University, is the “pipes that lead from the watermain to the house.”

She told CTV News Channel that a “very interesting problem” in Canada is the lack of “firm corrosion control guidelines.”

“In consequence, because we don’t have that kind of control, even in houses that don’t have lead pipes, in some circumstances, where the water is very acidic … the research showed that residents were experiencing … elevated levels (of lead), even if they didn’t have lead pipes,” Sonntag said.

If the water in your home comes from lead pipes, it’s your responsibility to replace them. That could cost anywhere from $5,000 to $10,000, said Cribb, who himself had to replace the pipes at his Toronto home.

But if the lead pipes are on the other side of the property line, replacement rests on government. What then? “Scream,” said Cribb. “Tell them they need to do it. Make a lot of noise. Talk to your neighbours. Create political pressure. The fact is that this is not a joke. The health implications for this are very serious.”

Anna Clark, a journalist and the author of the book “The Poisoned City: Flint’s Water and the American Urban Tragedy,” said that a lack of proper corrosion control was one of the main issues in Flint.

Flint made headlines globally when residents started raising an uproar over the toxic water coming out of their taps after their water source was switched in 2014 to the Flint River.

Clark said the water was more corrosive, and officials were not “treating it at all for corrosion control -- something you add to the water at the treatment plant to help keep the metals (in pipes) from disintegrating into the drinking water.”

As Flint’s pipes degraded more, the water turned brown, she said, which was a sign of iron breaking down into it. Although the iron was “repulsive and alarming,” she said, “in fact, the most dangerous thing in their water -- the lead -- was not visible to the human eye.”

A lack of transparency and accountability from officials was the main reason the situation became so critical.

“In Flint … when residents were bringing up concerns, they were dismissed, and as they were dismissed, the problem escalated,” Clark said. “What changed was that they were able to partner with outside professionals to get more and better data that showed what was really going on. It contradicted what the state of Michigan had been saying.”

She added that “it sounds a lot like what happened in Canada: a vast collaborative effort generated more and better data to show what was going on with the drinking water when either the information wasn’t there, or it wasn’t good, or it wasn’t being shared transparently.”

Sonntag echoed Cribb and Clark’s points regarding accountability for officals, saying, “one of the things that the … investigation showed was that Canada’s problem with open governance and open data needs to be addressed.

“But I think there needs to be a national conversation about whether we should have a minimum drinking water standard.”

Sonntag pointed out that although lead poisoning affects young children and people who are pregnant the most, this new study about Canada’s drinking water has frightening implications for the entire population.

Men could experience more hypertension, she said, and older women may have a higher risk of Alzheimer’s if they contract lead poisoning.

“It’s a neurotoxin,” she said. “And it can affect us all.”