Michigan Gov. Rick Snyder is drinking Flint water for 30 days. It’s a stunt.

The water in Flint, Michigan, still isn't getting back to normal. And the political crisis brought about by national attention to the city's lead problem shows no signs of abating either. So Michigan Gov. Rick Snyder is trying to kill two birds with one stone: He announced that he'd be drinking (filtered) water from Flint for 30 days to to try to restore residents' confidence.

But Snyder could struggle to get this message across for both political and scientific reasons. His approval ratings have plummeted, and a recent poll found 44 percent of Michigan residents think he's doing his job poorly.

Plus, because of the way lead poisoning works, an adult drinking the water doesn't tell you anything about whether it's safe for children to drink.

That's because if you have to be drinking water that's potentially laced with lead, you're least likely to suffer damage if you are, like Snyder, a middle-aged man. Lead in water is particularly harmful to children, whose brains are still developing; to pregnant women; and to the elderly. And while lead isn't good for adults either — at too high a concentration, it can cause symptoms like decreased libido, fatigue, and forgetfulness — it takes much more lead in blood to produce those effects. For children, even a few micrograms of lead can lead to developmental delays.

The good news is that the water in Flint really is improving: The Virginia Tech researchers who uncovered the crisis in the first place say the amount of lead in the water is dropping, although it's still too high. And with water filters in place, most homes — although not all — have water that's safe to drink. Snyder isn't really putting himself at risk. But he's unlikely to inspire much confidence.

Go deeper:

• A map of lead exposure in every neighborhood in America, from Vox's Sarah Frostenson.
• The Flint water crisis is such a big deal because it exemplifies problems that go far deeper than a single city.
• Kevin Drum at Mother Jones, who has written extensively about lead poisoning, argues that we're blowing the crisis in Flint out of proportion — and that it's damaging the conversation about lead in America.