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Public Radio's Environmental News Magazine (follow us on Google News)

July 9, 2004

Air Date: July 9, 2004



The Secret Life of Lead, part 1

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Living on Earth’s hour-long documentary "The Secret Life of Lead" opens with host Steve Curwood visiting the neighborhood around researcher Kim Dietrich’s office. Dr. Dietrich has been following almost 300 young men and women there for the past two decades in an attempt to unravel the effects of childhood lead exposure. Most recently, his research has shown that lead exposure can lead to an increase in juvenile delinquency. (13:00)

The Secret Life of Lead, part 2

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Three young adults who are part of Dr. Dietrich’s research group tell stories of their troubles with the law, and problems they've faced in their lives. Bruce Lanphear, lead researcher and head of the new environmental health center at Cincinnati Children’s Hospital, explains the connection between lead and crime. Dr. Lanphear is beginning a new study and is recruiting 400 pregnant women in an attempt to further reveal the impact of lead on child development. (19:00)

The Secret Life of Lead, part 3

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Host Steve Curwood discusses the history of lead paint in the U.S., and the challenges scientists face when they conduct lead research. Science, though, has provided the basis for all public policy decisions limiting lead in the environment. Dr. Bruce Lanphear’s new study will examine the effects of extremely low levels of lead on children. But recruiting women for this new project isn t an easy task. (16:30)

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HOST: Steve Curwood


CURWOOD: From NPR, this is Living on Earth. I’m Steve Curwood. Today we visit Cincinnati, where scientists are trying to understand how children who are exposed to tiny amounts of lead may lose critical coping skills for the rest of their lives.

LAQUISHA: If I just don’t sit down, and just be still, and just try to cool down, I just blow up. I just be so mad, but I just can’t help it sometimes.

CURWOOD: Researchers have found a strong link between lead poisoning and delinquent behavior, and think that may predispose these children to commit crimes as adults.

DIETRICH: I guess the way I think about lead is that the environment these children are living in--the environment of drugs, easy access to guns--I guess I would say the environment provides the opportunity. Lead may pull the trigger.

CURWOOD: The secret life of lead, this week on Living on Earth, right after this.


ANNOUNCER: Support for Living on Earth comes from the National Science Foundation and Stonyfield Farm.

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The Secret Life of Lead, part 1



CURWOOD: Welcome to Living on Earth. I’m Steve Curwood in Cincinnati. And we’re here to take you on a journey. But we won’t be boarding the paddle wheelers that cater to tourists along the Ohio River waterfront of this Midwestern city, or the tour buses that frequent the famous Cincinnati Zoo. No, today we embark on a voyage of scientific discovery with a team of researchers at Cincinnati Children’s Hospital and the University of Cincinnati. They have let us into their lives and laboratories to help us learn how cutting edge science does its work; to help us understand how years of hard labor, false starts, and moments of inspiration can lead to scientific breakthroughs.

For more than two decades, the Cincinnati research team has been trying to unravel the scientific secrets relating to childhood lead exposure, and this step-by-step process is far from finished. Our story on this emerging science doesn’t begin in a room filled with test tubes and people with white coats, but in a modest, tidy living room on the outskirts of the city.


DIANA: Tony…you are so disrespectful…enough is enough.

CURWOOD: Tony is in trouble again. His mother Diana says it’s nothing new for her 22-year-old.

DIANA: He can’t hold down a job. He can’t keep a steady girlfriend. His mind, it’s like his mind races.

CURWOOD: And Tony’s troubles today look much like the ones of his early years when his family lived in a gritty neighborhood downtown.

DIANA: It was hard, especially trying to raise three other children who, quote unquote, was pretty normal, but then you’ve got this child you just can’t figure out what’s going on. It was a tear in our marriage. And then you’ve got this kid, every time you turn around you’re getting a phone call to come and get him.

CURWOOD: Diana and I talk while Tony wanders in and out of the house, yakking on his cell phone, meandering up and down the stairs. He says he wants to talk with me but it seems like he just can’t sit down.

DIANA: Tony, are you ready for your interview?

CURWOOD: Finally, Tony sits down to chat. He squirms as he tells me about life in grade school.

TONY: Couldn’t concentrate. I was wild. I wanted to be over here talking but I had to do my work over here. That was rough right there. That was always a concentration thing with me. I guess they thought it was like, well, he has a behavior problem or whatever. It was just I didn’t want to sit down. School, it was just rough, man, from first grade to 11th, it was just rough.

DIANA: He’s very smart. He can be a very sweet child. He’s just not…his attention span--Tony doesn’t have a good attention span at all. And he’s been diagnosed with ADD. And I don’t know if that’s part of him having lead, or it could very well just be part of my genes that he has.

CURWOOD: Indeed, that’s the question scientists who have been following Tony all his life would like to answer. Like millions of American children, Tony spent his early childhood in an apartment that was loaded with dust from lead paint. But unlike most of those children, Tony’s exposure to lead has been carefully documented since he was in his mother’s womb. He’s one of nearly 300 individuals being followed by the research team in Cincinnati that is probing the long-term effects of lead. Neuropsychologist Kim Dietrich has been studying this group for more than twenty years.

DIETRICH: We recruit them prior to birth and then follow them over a period of time, measuring the amount of lead they’re exposed to by measuring the amount of lead in their blood, and their behavior. Sequentially. And thus, we can correlate earlier exposure to lead, which we have a good record of, with later behavioral problems.

CURWOOD: When he was a toddler, Tony had levels of lead in his blood that today would be considered cause for concern. But back then, lead exposure was only officially a cause for concern at levels approaching those that could lead to seizure or death. Still, there were some signs that childhood lead exposure in much smaller doses could have an adverse impact on learning and behavior. Trouble was, most kids who were identified with elevated lead exposures were also poor, and many were black. Some said their problems could be blamed on poverty and race. Many were skeptical that lead was playing any large role, among them Kim Dietrich himself.

DIETRICH: There are certainly children who are not poor that get lead poisoning. We know that for certain. But it is predominantly seen in children living in situations that present other challenges to optimal development, including poor nutrition, perhaps in some cases inadequate caretaking and supervision and stimulation. And so, I was skeptical. I thought that since lead was correlated with these other factors, it was probably these other factors that were responsible for the effects that were observed. And there was only one way to really tease this out. And that was to conduct a different kind of study we call a prospective study.

CURWOOD: In a prospective study, a group of people are followed over a period of time to see who gets sick and why. Lead exposure had never been studied this way before. Most of the 300 people recruited for the study first lived here, in Over-the-Rhine, a neighborhood near downtown Cincinnati that’s seen better days. Its name comes from the German immigrants who moved here in the nineteenth century. Tony spent his first years in an apartment only a few doors away from the clinic where Kim Dietrich has his office. On a snowy day, Dr. Dietrich and I set out for a tour of the neighborhood. Near the front door of the clinic a sign says “BMF.”

DIETRICH: BMF stands for Babies Milk Fund. And it –

CURWOOD: Babies Milk Fund?

DIETRICH: Babies Milk Fund, right. Because it was originally established to provide vitamin D-enriched milk to prevent rickets in children who were not getting adequate nourishment living in the community.

CURWOOD: Today, almost every family here lives below the poverty line and many people still go hungry. They make do in shabby apartment houses that share the streets with abandoned properties. Many of the facades of these decaying buildings are adorned with intricate carvings that recall how grand this neighborhood once was. And as this elegance has faded, it has shed lead paint dust and chips on the ground.

DIETRICH: As a matter of fact, in neighborhoods like this, the soils and other surface areas can have concentrations of lead which are equal to or greater than that which you would find in certain mining communities where lead had been mined for decades.


DIETRICH: Poor people have, many times, no choice but to live in communities like this where the housing is not well-maintained. And, as a result, they are essentially trapped in this world of lead.

CURWOOD: God, look at this place. This one is occupied but next to it is a vacant building where the windows are cracked.

DIETRICH: But it is for rent. And so at some point in time, a family is going to move into this apartment, and I can tell you for certain that there are significant lead hazards in this building just by looking at the exterior. If we were able to get inside we would very likely find base boards and windowsills with peeling and cracking paint. And the thing you have to understand here, or at least appreciate, is that this is one house, but it’s not a question of one house and one child. This lead-contaminated apartment here is going to poison more than just one child because there’s going to be families moving in and out and in and out of this apartment over and over and again.

CURWOOD: Back when Kim Dietrich started his study, the Centers for Disease Control set the official threshold of concern for lead at 30 micrograms per deciliter of blood. Most of the children in his research group, or cohort as it’s called, did not have obvious physical signs of lead poisoning but had exposures around the level of concern. It didn’t take long for Dr. Dietrich to see results.

DIETRICH: We found a number of things. We found that even exposure in the womb was associated with lower birth weight in our cohort. It was associated with a slower rate of early sensory motor development. Later on, we found that earlier lead exposure was associated with lower IQ.

CURWOOD: And this was true even when Dr. Dietrich took into account other factors, such as the mother’s IQ, the quality of childcare, and the child’s nutrition. Kim Dietrich measured other aspects of neurological development through specially designed games and tests.

DIETRICH: We have found over the years that lead exposure is associated with a number of motor symptoms. Children with higher exposure to lead had difficulty in engaging in fine motor tasks. They had poor postural stability. In other words, they were not as coordinated as their peers who were exposed to lower levels of lead.

CURWOOD: In 1991, the work done by Dr. Dietrich and other leading researchers prompted the government to tighten its threshold of concern for children down to 10 micrograms of lead per deciliter. The Cincinnati study was one of several that began in the early 1980s. Today, this is the only long-term study still intact.

DIETRICH: When you follow a cohort for over 20 years, it becomes much more than just a research study. You get personally involved with the families, with the sometimes troubles and crises they may have from time to time.

CURWOOD: Persistence is part of the research protocol here. And to keep people coming in for checkups and testing, Dr. Dietrich and his colleagues have spent many hours knocking on doors, holding holiday parties, even checking out the local laundromat to find no-shows. But the problems of keeping this study cohort together go beyond missed appointments.

DIETRICH: A great many, unfortunately, of the members of this cohort have had problems in terms of the justice system. More than a handful have been incarcerated and, unfortunately, one of the sources of attrition in our cohort is homicide. That is members of the cohort being killed either as a function of a drive-by shooting or engaging in criminal activity themselves.

CURWOOD: This violence and crime that is so much a part of life in this neighborhood may well be connected to their childhood lead exposure, says Dr. Dietrich. Two years ago, he published a study about delinquency and reported that the teens in his group with the highest lead exposures were much more likely to engage in delinquent behavior than teens with the lowest exposures to lead as children. Dr. Dietrich says he doesn’t know exactly how lead exposure can lead to delinquent behavior, but he does know that lead seems to compromise the abilities to focus and control impulses, and that is an important clue.

DIETRICH: For example, we know that children who have attentional deficits, poor impulse control, deficits in an area we call executive functions, that is a lack of ability to plan ahead, to anticipate consequences. We know that children who have these behavior deficits are at higher risk for engaging in anti-social behavior, and, ultimately, behaviors we associate with a high risk of arrests and adjudication for delinquency.

CURWOOD: For Kim Dietrich, lead very well might tip the balance when it comes to the ability to resist temptation.

DIETRICH: I guess the way I think about lead is that the environment these children are living in--the environment of drugs, easy access to guns--I guess I would say that the environment provides the opportunity. Lead may pull the trigger.

CURWOOD: Two decades into this research, Kim Dietrich’s subjects are now young adults. We’ll meet a few of them and hear about their problems with the law, and see how researchers hope to learn more about the secret life of lead, coming up right after this.

[MUSIC: Carl Craig “A Wonderful Life” Back to Mine/Everything but the Girl (Ultra 2001)

CURWOOD: You’re listening to NPR’s Living on Earth.

[MUSIC: DJ Cam “Friends and Enemies” Back to Mine/Everything but the Girl (Ultra 2001)]

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The Secret Life of Lead, part 2


CURWOOD: Welcome back to Living on Earth, I’m Steve Curwood in Cincinnati. We’re home again with Tony. He’s a 22-year-old who was exposed to lead as a child.

All his life, researchers have been monitoring him as part of a study of the long term effects of lead. Like many in the study, Tony has trouble concentrating. He says he can’t keep a job or a steady girlfriend. In fact, it was hard for him to sit down and talk. For Tony, life is chaotic. But there is one way Tony can deal with the world around him. That’s his music.


TONY: The studio’s like my own little world, man. Once I’m in there it’s like my own world, man. I’m separate from everybody, man, everybody.

CURWOOD: So, what do you do in the studio when you go there?

TONY: I’m all over, man. I’m an artist. I might help you produce a track. I might just sit there and mess with the mix board, make sure your vocals and everything are right. I’m everywhere, man.

CURWOOD: Music is the only thing that can capture Tony’s attention for any length of time. It’s been that way all his life. Back in elementary school he says his teachers constantly complained about him not paying attention and acting out in class.

TONY: Hyper, man, that’s probably the perfect word for me, man. Hyper, man.


TONY: Hyper, yeah.

CURWOOD: Then, when he was 14, Tony started life “on the streets,” as he puts it. Selling drugs was easy money.

TONY: You don’t think about the consequences. You’re out here making money, doing it illegal. One day might make 400, next day you might make 900. Now you got something you can do, you know what I’m saying? “Tony, we’re going to go out.” Well, I got a little money in my pocket, I can go out, too, come on. Know what I’m saying? And then you go out, one thing lead to another. It was like that.

CURWOOD: Did you get hurt at all?

TONY: Yeah, I got stabbed…

CURWOOD: Yeah, what happened?

TONY: Got shot right here. And I got stabbed on my stomach.

CURWOOD: That’s rough.

TONY: That’s the street life, man.

CURWOOD: So, what changed your mind about the street life?

TONY: Came about 2000, my son came.

CURWOOD: You got a boy?

TONY: Yeah, I got a son. When he came, it was just like, it was, it was just something that clicked with me. You know what I’m saying? Either you’re going to be here with him or you’re going to be here by yourself. My father was always there for me, so I figured I got to be there for my son. It was either leave the streets alone and raise him or don’t raise him and end up in jail or dead. So I took the other way.

LAQUISHA: All right, my first name, Laquisha. I’m 18 and I live in Janann Hills.

CURWOOD: Laquisha is part of the same lead study that follows Tony. Like Tony, she has to come here to the clinic for regular check-ins. And like Tony, Laquisha has spent some time in jail. But it’s not drugs that get her into trouble, it’s her temper. She gets into fights easily and was kicked out of public school. Laquisha seems quiet enough. It’s hard to imagine her blowing up. But if something sets her off, she just can’t help herself.

LAQUISHA: And I be trying to get help for it. But for real, for real I don’t know how to go about doing it. But sometimes I just get so mad. It could just be over little stuff and if I just don’t sit down and just be still and just try to cool down, I just blow up and just start tearing everything up. And I don’t be liking to be that way because after I get finished it be like, man, like why did I do this? I just be so mad. But I just can’t help it sometimes.

CURWOOD: Laquisha has been to anger management class but it didn’t seem to help much. Not only does she easily lose her temper, she also easily loses her train of thought.

LAQUISHA: Like, I’ll be focused for a minute and then I just get on something else. I don’t know what’s be happening and I be asking my momma, like, and my momma just be like, you know what I’m saying? You got to forget about everything else and really concentrate. And I’ll be telling her, like, one minute I’m concentrating and then I just go out of focus like.

CURWOOD: At the Cincinnati Children’s Hospital, researchers have joined in the effort to see if the troubles of people like Tony and Laquisha are a function of their exposure to lead in early childhood. Certainly they had lead levels that today would be considered unacceptable. And lead is a potent neurotoxin. That means it can interfere with the brain’s chemicals, functions, and development. But science is not yet able to draw a straight line between lead poisoning and any given act of antisocial behavior. Bruce Lanphear heads the hospital’s Environmental Health Center.

LANPHEAR: There’s some evidence from the animal literature that it can alter either the binding of neurotransmitters or the release of neurotransmitters. But, again, the specific mechanism that causes any particular problem, whether it’s intellectual impairments, or lower IQ scores, or whether it’s impulsivity, or attentional problems, we don’t know what the connection is. And it may be more than one.

CURWOOD: Lowered IQ, trouble with learning, poor impulse control, and the lack of ability to plan ahead, all make it harder to make good choices in bad situations. And Dr. Lanphear says more studies are providing additional support for the link between lead and crime. For example, recent findings by University of Pittsburgh researchers show that teens with a history of lead poisoning are twice as likely to be considered delinquent by the law, their school, or their family.

LANPHEAR: So there’s actually quite a bit of evidence that begins to link lead as a potent neurotoxin and conduct disorder, or antisocial behavior, or criminal behavior. And while it’s always very difficult, because it’s a very charged topic, to make any definitive links, there certainly is a growing body of evidence that really substantiates some of the work that’s now been ongoing for over 20 years.

CURWOOD: To help unravel the secret life of lead, Bruce Lanphear and Kim Dietrich are heading up a five-year, multi-pronged study funded by the National Institute for Environmental Health Sciences. As part of this new round of research, they are conducting two unprecedented studies on lead and crime. Both involve Kim Dietrich’s research group that includes Tony and Laquisha. One study seeks to identify any physical changes in the brain.

LANPHEAR: We’ll take that same group of children, now young adults, and using imaging techniques try to see whether lead exposure impacts the function, or make-up of the brain. So, are certain parts smaller or more dense, for example. Does that tie into the delinquency that we’re seeing?

CURWOOD: Another study asks these same young adults about their behavior and screens them psychologically. By correlating results with known childhood lead exposures, researchers will try to tease out what influence, if any, lead has on adult anti-social behaviors.

COMPUTER: Please enter the subject’s last name, enter the code.

CURWOOD: Most people are reluctant to discuss criminal behavior, so the team has designed a talking computer program in the hopes it’ll be easier to confess to a machine.

COMPUTER: Please enter the subject’s six digit ID, enter the code.

CURWOOD: Louis, a young man with bright yellow shirt and a shy smile, sits at the computer. He’s in the neighborhood office of Kim Dietrich today for his psychological testing. After his one-on-one confidential interview with a research assistant, the computer queries Louis for about an hour.

COMPUTER: How many times in the last year have you purposely damaged or destroyed property belonging to your parents or other family members? Type a number for your answer. Your answer was number 2, once…

CURWOOD: Louis has been coming to the clinic since he was an infant. Some of his earliest memories involve playing games here.

LOUIS: They had little Sesame Streets on the walls. The Oscar and all the Sesame Street characters. They’d give us little toys and stuff.

CURWOOD: You’re smiling when you talk about this. Sounds like you really liked coming to visit here.

LOUIS: Yeah, it’s all right.

CURWOOD: Didn’t they poke you with needles, and want to take blood?

LOUIS: Nah, that ain’t that bad. That ain’t a bad part. Nah. They’d keep you comforted while they do that.

CURWOOD: So, this was a fun place to come to?

LOUIS: Yeah.

CURWOOD: For Louis, life away from the neighborhood lead clinic was not as kind. He’s lived in 28 foster homes. He’s been in and out of jail for robbery. And he was even featured in a local newspaper story about kids from a city high school who were having a tough time getting by.

CURWOOD (TO LOUIS): Some of the lead research shows that people who’ve had this question of lead are twice as likely to wind up dealing with the juvenile system, if they hadn’t had it. Think it had any effect on you like that?

LOUIS: I don’t know. Might have, might haven’t. My record is…probably yeah, probably yeah.

CURWOOD: Louis is now out on parole on a robbery conviction. He says he doesn’t want to go back to jail, but in his world he feels his options are limited. His rap says it all.

LOUIS: Now people want to know how I make a living. The same way you do, the only difference is I’m dealing. I’d rather live my life on the straight road and do a legal, I only end up running back to the arms of evil. I got to see and I can’t stand to watch the store. I’d rather sell dope and make it look like we live large. And take the charge. Pay lawyers so I don’t do long behind bars. When I get out, back on block, I’m still waving down cars. And it’s a new way to hustle every time I get out. It seems that every day my momma’s always cussing me out. She’s gonna leave, but I love her, and it’s stressing me more. And I can’t leave this game knowing that my pockets are sore. So I stay grounded not knowing what tomorrow will bring and I wonder… that’s it now. Cut it off right there.

CURWOOD: Bruce Lanphear says while much of the dangers of lead are well documented, society has remained relatively indifferent to the problem, with millions of homes still contaminated by lead paint. That makes it important, he says, for people to understand the link between lead and crime.

LANPHEAR: Partly because, right now, many families and many decision-makers in the United States feel like lead doesn’t affect them at all. I think to the extent that we begin to recognize that lead, or any other toxins, or any other risk factors for that matter increase the rates of criminal behavior, that’s something people feel vulnerable to. Criminals cross over from one neighborhood to the next. And so, when we begin to make connections between lead and criminal behavior, that’s something that people can’t just say, that’s fine, it affects inner city kids, it doesn’t affect my kids. They can’t say that about crime.


CURWOOD: The Cincinnati lead team has learned a great deal about the effects of lead but there is still much more work to be done. So at the University of Cincinnati Hospital, Bruce Lanphear’s team is recruiting a whole new cohort of pregnant women. Some of the data to be collected will be used to verify results so far. Other data will break new ground these scientists hope. And nothing can happen without new moms. Amy Kalkbrenner is in charge of enrolling 400 pregnant women and keeping them and their children coming back for the next three years, if not longer. Not an easy task. Today, the soon-to-be-moms are coming in for their first doctor’s appointments and Amy waits at the hospital’s obstetrics clinic, constantly checking and re-checking her notes

KALKBRENNER: Just because we’re at the very beginning of the study, and so this is new to me, as well as being new to the staff. And often times what I’ll do when something is just absolutely brand-spanking new and unexpected, I don’t like to ask my staff to just jump in and do it. Because I don’t want to put them in a tremendously uncomfortable situation. So, oftentimes I’ll sort of do the first few, see how it’s going, feel my way through it, model it a little for them. So it kind of puts the burden back on me to do the screening today.

CURWOOD: Ms. Kalkbrenner hopes to convince suitable candidates to be part of the new study. In exchange, they get some free home improvements and a few hundred dollars to spend at the grocery store. One question these women and their babies may help answer is how much lead is too much. Today, the official threshold of concern is 10 micrograms of lead per deciliter of blood. That’s drastically tightened from the 30 micrograms that was permitted back when Kim Dietrich started his cohort two decades ago. Yet Dr. Lanphear has already conducted short-term studies that show that even 10 micrograms may have harmful effects. Among 5,000 children, he found cognitive deficits from even these tiny amounts of lead, raising the question that there may be no truly safe levels of lead exposure for children.

LANPHEAR: From a population perspective, what we can say about lead exposure is that if there is no discernable threshold, and that’s what the research points to, then 90 percent of the children who are adversely affected by lead in this country never have a blood level that exceeds 10 micrograms per deciliter.

CURWOOD: Dr. Lanphear has also found that the greatest loss of IQ occurs in the earliest stages of lead toxicity.

LANPHEAR: So, going from a blood lead of less than one to a blood lead of 10, on average, is associated with about a seven-point drop in IQ. In contrast, if we looked at a population of children going from 10 micrograms to 20 micrograms per deciliter, there’s only about an estimated two and a half point drop in IQ.

CURWOOD: These new studies are expected to confirm these earlier results, says Dr. Lanphear. But, with evidence that even tiny amounts of lead can affect intelligence, the Cincinnati team wants to explore the role small amounts of lead could play in ADHD, attention deficit hyperactivity disorder. Dr Lanphear says if this research shows a link between lead and this widely publicized condition, it might spark broad public interest since millions of children suffer from ADHD.

LANPHEAR: I think the problem with looking at minor changes or decrements in IQ is that they’re subtle. They’re hard to measure. With ADHD it’s a clinical disease, it’s a clinical diagnosis. And if we can say there’s a 50 percent increase in ADHD for every 10 micrograms increase in blood lead, it may be that people understand that easier.

CURWOOD: For this new study, the team is recruiting 400 pregnant women from middle class and poor neighborhoods in and around Cincinnati. Half of the group will receive extensive home lead abatement.

LANPHEAR: We’ll go in, measure the home. If there’s lead in dust, lead in water, lead in soil, lead in the paint, if the paint is peeling or in disrepair…so if the dust lead levels are excessive, but we don’t find that the paint is in poor condition, we may just do a clean-up. In other cases, the windows may be in really poor shape. We’ll replace the windows. If there’s lead contaminated soil, we’ll do something to cover that up.

CURWOOD: Dr. Lanphear says these efforts should keep child blood lead levels from rising above three micrograms. A control group, involving the homes of 200 pregnant women, will not receive lead abatement. Dr. Lanphear anticipates children in these homes will have more learning disabilities and developmental disorders even though they will have blood lead levels that are considered safe by the government. But Dr. Lanphear doesn’t feel it’s right to improve the lives of half the group and doing nothing for the others. So, for the control group his team is providing help to reduce household hazards, the most common cause of death for children under five.

LANPHEAR: We will put stair gates in place. If indicated, we will turn down water temperature below 120 degrees to make it less likely to burn a child. We’ll put window guards in for multi-level dwellings where there’s over two stories. We will put latches or safety locks on cabinets where cleaners are kept, where medications are kept.

CURWOOD: So far, there are funds to evaluate all the children in the study at 12, 24, and 36 months. But Dr. Lanphear hopes his research will continue over the lifetimes of the children, providing data on the impact of lead for years to come, just as Kim Dietrich has done. But meanwhile, back at the OB clinic, there’s a little snag.

FEMALE: Okay, Christy as of yet has not shown in…

CURWOOD: Clipboard in hand, Dr. Lanphear’s project director Amy Kalkbrenner tells us she thought she’d be much further recruiting participants. She didn’t plan on speaking with these women for the first time today, but efforts to contact them by phone didn’t work much at all.

KALKBRENNER: And I guess I thought more of the time we’d find valid phone numbers. And it’s been about 75 percent of the phone numbers are just completely wrong.

CURWOOD: She later heard from nurses at this low-income clinic that wrong numbers are common here. The women move frequently, phones are disconnected, and sometimes, a wrong number might be given to forestall hospital bill collectors.

KALKBRENNER: I’ve actually been working to prepare this study for just a little over a year. Which is a pretty long time to work on something before it starts. I think this is the longest start-up time I’ve ever had. So, I guess the irony is that even after a year plus of preparation, when the day actually comes, there’s still just a lot of unexpected, a lot of unknown. I don’t want to say chaos, but a little bit of chaos.

CURWOOD: We’ll see how Amy Kalkbrenner does on her first day recruiting pregnant women for the new research cohort later on, but first, a look at the history and politics of lead research, right after this.

[Music: Deadly Avenger “The Bayou” Back to Mine/Everything but the Girl (Ultra 2001)]

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The Secret Life of Lead, part 3

CURWOOD: It’s Living On Earth, I’m Steve Curwood.


CURWOOD: Nineteen twenty-seven. “The Jazz Singer” wows audiences as the first talking feature film. Charles Lindbergh flies the first solo crossing of the Atlantic from New York to Paris. And in the face of growing evidence that lead paint is dangerous, especially to children, European nations are banning it in homes. But in the U.S., lead paint companies are politicking to keep their product on the market. Historian David Rosner.

ROSNER: They literally discuss in their meetings that lead poisoning is becoming prevalent. And they began to develop a campaign that literally tries to minimize the danger by saying that these are children who are relatively few in number, and the ones that are damaged are generally kids who are not being supervised by their parents, or, alternatively, have a disease called pica, which is a craving for non-food substances.

CURWOOD: While blaming the victims, the industry also moves to stifle the scientists who document the dangers of lead paint. When Randolph Byers, a pediatrician at Harvard Medical School, publishes his 1943 study showing substantial long-term harm from lead exposure, the lead industry threatens him with lawsuits and effectively silences him. In 1979, another Harvard researcher, Herbert Needleman, shows that supposedly safe levels of lead exposure in childhood correlate with learning disabilities and diminished IQ’s. The lead industry fires back. Two university–based scientists supported by the industry charge Dr. Needleman with scientific misconduct. He’s forced to defend himself in front of his funding agency, the National Institutes of Health, and his efforts to get tenured in academia are threatened. Eventually, Dr. Needleman’s research is verified. But the message was clear, says Don Ryan, executive director of the Alliance to End Childhood Lead Poisoning: don’t mess with the lead industry.

RYAN: Every step of the way, the lead industry challenged the scientific evidence, ridiculed the reality of lead’s low level health effects, and basically, claimed this problem was being completely overblown by scientists.

CURWOOD: Lead is still a risky topic for scientists who investigate it today, scientists like Bruce Lanphear at Cincinnati Children’s Hospital. Dr Lanphear says, at first, his work was pretty much ignored by the lead industry.

LANPHEAR: And, in fact, I always used to hear some of the more senior researchers complain about the lead industry getting involved in negative ways with their research. And they would say the lead industry sort of like it was a mafia. And I never really was aware of it, so I never quite believed it.

CURWOOD: That is, until Dr. Lanphear started to publish results showing that even very low levels of lead can reduce IQs. At that point, he says, his nomination to the lead advisory board at the Centers for Disease Control hit a roadblock.

LANPHEAR: Beginning in March of last year, I heard from a CDC official that while I had been nominated for over a year, that the lead industry was visiting with Tommy Thompson, or Tommy Thompson’s office, and putting forward their own nominations. And it was about a month or two later that he called me up and was very apologetic. And he said, you know, I’m sorry but we’re not going to be able to approve your nomination.

CURWOOD: Tommy Thompson is secretary of the U.S. Department of Health and Human Services which oversees the CDC. A department spokesperson would not discuss specific appointments but defended the nomination process and said nominees are chosen to represent a spectrum of viewpoints. Dr. Lanphear says he understands why the lead industry might feel threatened by his findings.

LANPHEAR: For example, in Rhode Island, if it’s recognized that children with blood lead levels over 10 are adversely affected by lead exposure, you may have three to four thousand children a year. Well, if it’s over five micrograms per deciliter, then you probably increase it by ten-fold. So, it’s fifty thousand to a hundred thousand children, and that’s just in one state. If there’s no threshold of safety, well, it’s millions of children every year in the United States. Millions upon millions of children. And so you can begin to see rather quickly, if you add up that numbers, that the lead industry doesn’t want that research, our research, to be recognized as valid.

LAWYER (FROM TRIAL): Good morning members of the jury. Like Mr. Scott, I also want to thank you for the time, and the effort, and the interest that you have shown in this case…

CURWOOD: In 1999, the state of Rhode Island took the lead industry to court to hold it accountable for poisoning tens of thousands of children. Both Bruce Lanphear and Kim Dietrich testified about the harm the toxin can cause when the case came to trial in 2002.

When I visited Dr. Dietrich in his Cincinnati office, he took out a bright yellow plastic container. It looked like a big lunch box, but it was covered with poison stickers. Inside, a few vials cushioned in foam. Dr. Dietrich held one up to the light.


DIETRICH: In the interior of homes, the clearance level for dust on floors is 40 micrograms of lead per square foot. And this would equal or exceed the clearance level, the EPA clearance level, for dust on floors.

CURWOOD: I don’t see nothing.

DIETRICH: That’s right. That’s the point, isn’t it? But it’s really there. There’s 40 micrograms of lead paint dust, or lead dust, in this vial. And so, you can see how difficult it is to detect, and, also, for parents to realize there is a hazard there and to work to eliminate it.

CURWOOD: This stuff is potent.

DIETRICH: Yeah. You can see why they didn’t want me to show that to the jurors.

CURWOOD: Industry attorneys argued that lead would never occur in such a pure form in the home, but would always be accompanied by some amount of dust. This demonstration was therefore misleading, and should not be allowed as evidence. The judge agreed and the jury never saw Dr. Dietrich’s vials. The trial ended with a hung jury in October of 2002. The lead industry has failed to respond to repeated interview requests from Living on Earth about the Rhode Island case and lead research. But Sheldon Whitehouse, who tried the case as attorney general of Rhode Island, didn’t mince words when he spoke to the press after the trial.

WHITEHOUSE: Every day, more kids are lead poisoned in Rhode Island. And the longer it takes to bring this case to conclusion, the more kids remain lead poisoned. And the longer the defendants are intransigent about doing one darn thing to try to be helpful in Rhode Island, as opposed to litigious, then the longer it is and the more it is that children continue to be poisoned.

CURWOOD: There’s a personal reason for the passion of Sheldon Whitehouse over what he calls the wrongs of the lead industry.


CURWOOD: Hi, you must be Sheldon Whitehouse.


CURWOOD: Hi, I’m Steve Curwood, from Living on Earth.

CURWOOD: I met Mr. Whitehouse in Providence on a rainy spring morning, and we sat around the dining table of his exquisitely restored Victorian. Those renovations had created a beautiful home but, as it turns out, they had also poisoned his children with lead.

WHITEHOUSE: You know, a parent’s highest obligation is to protect his or her children. And when you find that right in your own home where they’re supposed to be safest, in fact they’re getting poisoned, you feel horrible, frankly.

CURWOOD: And then you get mad?

WHITEHOUSE: No, I don’t think there was really much to get mad about. It’s one of those systems things where it shouldn’t have happened. But it doesn’t just happen to me and my family. It happens to families throughout Rhode Island. It’s one of those things where nobody brings it up. But once it comes up--if you’re in a group of employed, upper middle class families, with cars and houses and taking their kids to schools, and private schools and all that sort of stuff--you start talking about it, and you find out people will admit, oh yeah, it happened to my daughter, too. Yep, my son had a high lead level. It’s sort of a, it’s almost like a dirty little unspoken secret that this is happening around here. I can see why people don’t talk about it because it’s embarrassing. You feel like you’ve failed as a parent when that sort of thing happens.

CURWOOD: Wait a second, the lead industry might say that, too. All these people whose kids have been poisoned, they should have known that, they should have conducted themselves in a better fashion, it’s their fault.

WHITEHOUSE: And they have been saying that. They’ve been saying that for a long time. They began saying it, most offensively, when it was poor black children in urban ghettos in Maryland. So that the rest of America could go by and say, look, we take care of our children, we don’t live in ghettos, and we don’t let our children eat lead paint chips the size of potato chips. So it’s not our problem. It’s okay. And what we’re finding out is that that ain’t so, it never was so. But there’s always been that pressure from the industry to try to marginalize the people who are suffering from this problem. And that has two effects. One is that it understates the problem dramatically. And the second is that people don’t feel that they need to pay attention to it. So, do I feel responsible for taking care of my children? I absolutely do. Was it my fault that this happened? Not entirely, but once you step into the fault arena, I think there’s a fair amount to go around in different places. We think landlords have a role, and that’s why we’ve been going hard after landlords in Rhode Island to make them clean up. But, by God, these paint companies have some responsibility, as well. And they are pretending that they have none and that’s just wrong.

CURWOOD: Sheldon Whitehouse’s term as attorney general has ended. But he predicts Rhode Island will continue to fight the lead companies in court. He draws an analogy to the tobacco liability cases which were won after repeated efforts and needed sound scientific research to counter the claims of the tobacco companies. Right now, Mr. Whitehouse says, research on lead is of critical importance to counter what he calls misleading information from the lead companies.

WHITEHOUSE: And it’s critical from a public health point of view that we lower the exposure of children to lead. And you can’t do that sensibly unless you’ve got the right information about how dangerous it is. So, this whole question about its toxicity has been an incredible saga. And we’re finally getting, I think, down to the point where we’re closing in on viewing it as being toxic at almost any level.


CURWOOD: Back at University Hospital in Cincinnati, Amy Kalkbrenner is still in the obstetrics clinic, as part of the work to get more information on the dangers of exposing children to miniscule amounts of lead. You may remember that she’s the project director for Dr. Lanphear’s new study that plans to follow 400 children from before birth through at least their early years. Ms. Kalkbrenner and a nurse are recruiting pregnant women for that study.

KALKBRENNER: Melissa, we’re going to give them juice boxes while they’re doing the consents.

CURWOOD: The consent process involves screening candidates and explaining what’s involved if they sign on.

KALKBRENNER: The consent’s really long. Down the road, we were going to give them water. We didn’t give them water yet, but we have all these juice boxes from another study. (LAUGHS)

CURWOOD: The juice boxes help ensure the women will be able to give a urine sample at the end of the interview. Ms. Kalkbrenner hopes to recruit at least a few of the 15 women who are here today for their first prenatal visit but it’s slow going.

KALKBRENNER: Do you want to find out if you are eligible? Not interested? Okay, thank you, Tisha. Did you want do find out whether you are eligible first or are you pretty sure you don’t want to do it? You’ve only been staying in a home for just the last couple of weeks. We’re looking for people who have been in the same home for three months, because we’re going to looking at your exposure to different chemicals in your home. So, I think you wouldn’t be eligible for this study today. I’m sorry but you’re not actually eligible. We’re looking for people who will be living in the same home during their pregnancy. Kind of anti-climactic. (LAUGHS) Okay, bye, thanks.

CURWOOD: By the end of the morning, Ms. Kalkbrenner has plenty of no’s and ineligibles, and a few maybes. But she says it’ll all work out.

KALKBRENNER: I recently have been accused by my staff of being an optimist but I always think, well, we’ll just get better from here. You know, next time, I don’t know, have more people we’re contacting, we’ll be more prepared. (LAUGHS). We’ll have that special smile that has somebody say yes instead of no. (LAUGHS) I don’t know what it is.


CURWOOD: In a small apartment in a Cincinnati suburb, technician Rick Hutchinson is conducting an environmental survey of the home of a woman who has agreed to be in the study.


HUTCHINSON: So what I’ll do here is I’ll mark off with tape the area that I’m going to sample here.

CURWOOD: He takes out a baby-wipe and methodically rubs it across the windowsill. It picks up dust and a few paint chips. He puts the wipe in a plastic vial that will be sent to a lab for lead analysis, along with the other samples gathered during a two-hour evaluation of this home.

HUTCHINSON: We have just one more dust wipe sample to take, and that’ll be off the kitchen.

CURWOOD: Stephanie Callahan’s apartment is well-maintained, with white walls and wood furniture. Other than around the windows, there’s no flaking paint anywhere in the apartment. This mom-to-be is a 23-year-old respiratory therapist. Relaxing on the couch with a cat in her lap, she says she knew right away that she wanted to be part of the study.

CALLAHAN: When I received the information in the mail, I was very interested. Probably just because of being a first-time mom. And also, I currently rent an apartment, and knowing that my first home was probably going to be an older home, it appealed to me just because I wanted to learn. To make sure that when I do get a home, and it’s an older home, making sure that there aren’t any things to worry about, such as lead or mercury, things that I would never even think about. Also, to get tips on, you know, household safety, maybe things that you generally don’t think about.

CURWOOD: Unless she conducts her own testing, Ms. Callahan will never know the results of the lead assessment of her home. Based on a random assignment, her apartment will either receive extensive lead abatement or childhood safety improvements. And her baby will be placed in one of two groups that will be monitored and their development compared. Stephanie Callahan says for her, the most important thing is the health and safety of her baby.

CALLAHAN: That was the whole reason to get into the study. I’m going to be a mom, and I want to do the best job that I can in raising this child.

CURWOOD: And so our story ends as it began, with a mother concerned about her child and the dangers from exposure to lead. Think back to Tony, now aged 22, and his mother Diana. The tragedy for them is that they can never go back to before Tony’s lead poisoning, to before his troubles in school, to before the gunshot wounds and troubles with the law. And his mother may never be able to stop worrying about her son. Stephanie Callahan can be grateful that, thanks in part to the research that involved Tony, the federal standards of lead safety have been tightened. That means that her unborn child will likely face far less lead in the home than Tony did. But Dr. Lanphear is still trying to find out if that will be safe enough. He should start to get some answers in a couple of years. And the original cohort of his colleague Kim Dietrich will keep revealing more data as it heads into its third decade.

Along the way, the team will have to secure continued funding, keep those cohorts together, and perhaps face more professional criticism. As a father of three, Dr. Lanphear feels a special urgency to find some answers.

LANPHEAR: I’m trying to do this because I think it will give children an opportunity to succeed. It will give them a better chance at having a healthy life. Children stand for hope. There’s always some promise that they hold out.

[MUSIC: DJ Cam “Friends and Enemies” Back to Mine/Everything but the Girl (Ultra 2001)]

CURWOOD: Over the months and years ahead, Living On Earth will keep checking in with Dr. Lanphear, Dr. Dietrich, Ms. Kalkbrenner and other members of the Cincinnati lead research team. We’ll tell you what they find out, and how they go about revealing the secret life of lead.

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And for this week, that’s Living on Earth.

The Secret Life of Lead was produced by Cynthia Graber, with help from Chris Ballman and was edited by Diane Toomey. For more about lead, visit our website, livingonarth.org. You’ll find a sound and photo montage, historical information about lead poisoning, links, pictures, and scientific research. That’s all at livingonearth.org.

Chris Engles is our technical director, Alison Dean composed our theme. I’m Steve Curwood. Thanks for listening.

ANNOUNCER: Funding for Living on Earth comes form the National Science Foundation, supporting coverage of emerging science; and Stonyfield Farm – organic yogurt, cultured soy, and smoothies. Ten percent of their profits are donated to support environmental causes and family farms. Learn more at Stonyfield.com. Support also comes from NPR member stations, the Ford Foundation, for reporting on U.S. environment and development issues, and the Geraldine R. Dodge Foundation.

ANNOUNCER 2: This is NPR, National Public Radio.


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