For months, people in Flint, Michigan -- a dying industrial town in the American heartland -- consumed water contaminated with lead. And the country ignored it.

But the public health crisis triggered by budget cuts has ballooned into an all-out scandal, with potentially catastrophic consequences for thousands of children.

This week, President Barack Obama weighed in, saying he would be "beside myself" if his children were placed at risk as kids have been in Flint, which is near Detroit.

Flint has fallen on hard times since most of its General Motors factories shut down. The city lost half its population, and a third of those left live in poverty.

Michigan's Republican governor Rick Snyder is in the hot seat.

"To you, the people of Flint, I say tonight as I have before: I am sorry and I will fix it," Snyder said Tuesday.

The next day, he was forced to release 273 pages of emails revealing his botched handling of the crisis.

Many are calling for his resignation, among them film director Michael Moore, who is from Flint and even wants the governor arrested.

- Brownish color -

As part of cost-cutting, the city began drawing water from the Flint River in April 2014 rather than continuing to buy it from Detroit. The river was known to be dirty.

Officials are accused of ignoring months of health warnings about the foul-smelling water, even as residents complained that it was making them sick.

The scandal has been exacerbated by the seemingly nonchalant attitude of city officials to the outcry from residents, many of them poor African-Americans.

Soon after the shift to river water, people started complaining about the taste, smell and murky color of the liquid coming out of their faucets.

Some said they were having skin problems, or their hair was falling out, or they were having other medical issues. All they got was advice to boil the water before using it.

In October, one of the last General Motors plants still running in Flint said it would no longer use local water because it was corrosive -- so toxic it ate away at the lead pipes in the plumbing system and exposed people to lead poisoning.

Research shows the presence of lead in the blood of children, even at low levels, can stunt their development seriously and irreversibly -- in particular, the development of their brain.

It will still take months to determine how bad the water in Flint really is.

The scandal broke thanks to the dogged efforts of a mother named LeeAnne Walters. She had the water at her house analyzed after city authorities told her the problem was probably with her plumbing system.

She received support from an independent expert at Virginia Tech University, Marc Edwards.

"I worked with LeeAnne Walters early one morning in April 2015, to collect samples revealing the extent of lead in water contamination in her home. Her child had been lead poisoned," Edwards told AFP.

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"We found hazardous waste levels of lead in her water, and that data and our other analysis were in a report written by an EPA employee who raised the alarm about the problem," he added. "After, that EPA employee was silenced and discredited."

"We formed a 25-person team, to partner with Flint residents, and to examine every aspect of their water safety. We funded the study and provided expertise," he said.

"When we had enough data in late August, we published a warning to residents, that they should not drink the water because of the lead in water contamination."

Millions of Americans have since been shocked by the events in Flint, which are finally gaining national traction.

And heads have started to roll.

The Environmental Protection Agency on Thursday announced the resignation of Susan Hedman, its director for the region that includes Michigan.

"It's ironic when you live in the Great Lakes State and we don't have access to clean water," Flint Mayor Karen Weaver said this week. Weaver was received Thursday at the White House.

"I am glad that we are getting the attention that we finally deserve to have," Weaver said. "Our kids have been damaged by this lead poisoning."

South African comedian Trevor Noah, the host of "The Daily Show," joked about Flint, suggesting a fundraising campaign in Africa "to save a village in America and get these people drinking the water that they so badly need."