RENEE MONTAGNE, HOST:
This week, we've heard a lot about the water crisis in Flint, Mich. Lead was discovered in Flint's water supply shortly after the city got a new water source in 2014. It is now known that lead poisoning goes back to Roman times, which left us wondering about lead's history. So we turned to Howard Markel. He's a pediatrician and the director of the Center for the History of Medicine at the University of Michigan. Thank you for joining us.
HOWARD MARKEL: Thank you for having me.
MONTAGNE: There was a time when lead was pretty common. I know that little toy soldiers back 80, 90 years ago were made out of lead. Was there a turning-point in time where it became really clear to everybody that lead did not need to be in the vicinity?
MARKEL: Yes. It was used for toys, and a real big culprit was it was in paint because it flakes off so easily. So if you had a stain on the wall, you could just wipe it off. But that makes the lead fine and particulate and easy to breathe in and ingest. The thing about lead chips, by the way, is they taste very sweet. So if you remember those old Necco wafers - those little tiny discs of sugar - a lead paint chip taste quite much like that. You know, as early as 1913, we knew that very high doses were extremely toxic. But it's really been since the 1990s by some very brave pediatricians who really put their careers on the line that discovered that these very low doses causes behavioral problems. And for many years, there were some people who were contesting this. But as time has passed since the 1990s and every year since, we have learned that lower and lower levels of lead are toxic. I would say that zero is the only normal number for any child.
MONTAGNE: What's taken the U.S. government so long to reduce the amount of lead it deemed safe, and then why isn't it zero?
MARKEL: That's a political, social, racial and economic question where the lead really does exist today - in older housing. So any house that was built before World War II is likely to have lead paint on its walls, even though it may have been painted over many times. Well, those homes happen to often be in urban centers. They are often inhabited by poor people. And they're owned, frankly, by slumlords who don't take care of the houses. It would cost maybe $30 or $40 billion to rip all these homes in inner-city Detroit or inner-city Baltimore or what have you and then to build new homes where people could live safely. But we've never had the political will to get rid of that problem. And instead, we've kind of minimized or abated certain houses at certain times. That is not good enough.
MONTAGNE: Is there treatment - good treatment - for lead poisoning?
MARKEL: No. For kids with really high lead levels, we give a chelating agent. It's a chemical that will bind to the lead, and then you will get rid of it. But that's for very high lead levels. And so the best treatment is absolute prevention. And, you know, prevention is something we have really favored for so many diseases in the 20th and now the 21st century. I think lead is the next problem we have to attack.
MONTAGNE: Thank you very much for joining us.
MARKEL: Thank you so much.
MONTAGNE: Doctor Howard Markel is director of the Center for the History of Medicine at the University of Michigan. Transcript provided by NPR, Copyright NPR.