Jessica Pupovac

The residents of Flint, Mich., received some welcome news this week: Researchers released the results of a new round of water tests, showing lead levels in that city's water system falling just below the Environmental Protection Agency action level.

Too many water samples above that level is a red flag for utilities, a sign that they may have a broader lead problem.

Virginia Tech researcher Marc Edwards, who leads the team documenting Flint's water problems, called the new results the "beginning of the end," a turning point in the city's saga with corrosive water.

Lead problems with the water in Flint, Mich., have prompted people across the country to ask whether they or their families have been exposed to the toxic metal in their drinking water, too.

When it comes to assessing the risk, it's important to look in the right places.

Even when municipal water systems' lead levels are considered perfectly fine by federal standards, the metal can leach into tap water from lead plumbing.