Democratic presidential hopeful Bernie Sanders wondered during Thursday's Democratic debate whether a toxic water crisis like the one in Flint, Michigan, would happen to a town that's not majority black.

"One wonders if this were a white suburban community what kind of response there would have been," Sanders said, to cheers from the audience. "Flint, Michigan, is a poor community. It is disproportionately African-American and minority, and what has happened there is absolutely unacceptable."

Flint's water has been unsafe to drink since 2014 because the state failed to treat the water so it wouldn't corrode lead pipes, resulting the deadly neurotoxin poisoning the water. A little more than half of Flint's 100,000 residents are black.

The state government, helmed by Gov. Rick Snyder (R), said water was safe, despite Flint residents' complaints (the water was brown) and warnings of serious problems from some state officials.

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Sanders called for Snyder's resignation last month.

"I don't go around asking for governor's resignations every day," he said Thursday. "In fact, I think i never have in my life, but I did ask for the resignation of Gov. Snyder because his irresponsibility was so outrageous."

Snyder admitted mistakes had been made at the end of last year, following a report of higher blood lead levels in Flint kids.

Former Secretary of State Hillary Clinton, for her part, has previously wondered whether Flint's water crisis would happen in a wealthier white suburb. She said she'll be traveling to Flint on Sunday and that the government response hasn't been sufficient. She said the federal government should make the state of Michigan pay to fix pipes and offer extra educational support for Flint kids.

"I think the federal government has ways where it can bill the state of Michigan," Clinton said. "And if Michigan won't do it, there has to be ways that we can begin to move and then make them pay for it and hold them accountable."

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