Childhood Lead Exposure: Piling Disadvantage onto Some of the Country’s Most Vulnerable Kids
Sheryl Magzamen, PhD, MPH, is an assistant professor in the College of Veterinary Medicine and Biomedical Sciences at Colorado State University and an alumna of the Robert Wood Johnson Foundation (RWJF) Health & Society Scholars program (2007-2009). She recently published two studies exploring the link between early childhood lead exposure and behavioral and academic outcomes in Environmental Research and the Annals of Epidemiology. She discusses both below.
Human Capital Blog: What are the main findings of your study on childhood lead exposure and discipline?
Sheryl Magzamen: We found that children who had moderate but elevated exposure lead in early childhood were more than two times as likely as unexposed children to be suspended from school, and that’s controlling for race, socioeconomic status, and other covariates. We’re particularly concerned about this because of what it means for barriers to school success and achievement due to behavioral issues.
We are also concerned about the fact that there‘s a strong possibility, based on animal models, that neurological effects of lead exposure predispose children to an array of disruptive or anti-social behavior in schools. The environmental exposures that children have prior to going to school have been largely ignored in debates about quality public education.
HCB: Did the findings surprise you?
Magzamen: Yes, because they were so strong. We know, for example, that African Americans are more likely to be suspended from school than White children (often for reasons relating to poverty). But lead exposure explains almost a quarter of that disparity. This legacy of early childhood exposure to a neurotoxin that’s basically been banned in the United States since the 1970s is still having lasting effects on our most vulnerable populations: low-income children in urban environments.
HCB: And what were the main findings from the study on childhood lead exposure and educational outcomes?
Magzamen: For this study, we looked at early childhood lead exposure and early childhood outcomes in fourth grade using standardized tests. What makes this analysis different from previous studies is that we surveyed parents to get more information about their child’s other health issues, such as the child’s health history, educational background, and socio-economic status. This kind of information was not included in earlier studies. We included it in our study so we could figure out some of the additional factors that may change the relationship between childhood lead exposure and educational outcomes.
HCB: Did the findings of this study surprise you?
Magzamen: We found a consistent relationship between early childhood lead exposure and end-of-school grades in fourth grade. What surprised us was how much other health factors were related to a child’s educational achievement. For example, children whose health was rated “fair” by their parents scored 25 points lower on the reading section of the end-of-year exams than children whose health was rated excellent by their parents.
The relationship between self-reported health and educational outcomes was almost as strong as the relationship between race and educational outcomes. We don’t know the etiological link between health and success in school, but we know there’s an incredibly strong relationship. These kids, due to lead exposure and other factors, are starting school with an incredible disadvantage. We feel these issues have been really absent from the discussion about public education in this country.
HCB: Do these studies suggest that childhood lead exposure is more dangerous than most believe it to be?
Magzamen: I don’t know if it’s more dangerous, but I think it has broader implications than we initially thought. We don’t know what’s going to happen to these kids, but we do know that educational success is linked to so many things later in life—not only to one’s ability to earn a living but also to one’s long-term health. These children are starting with so many disadvantages, and it’s so much harder to make up for those disadvantages later in their lives. We have known the power of lead to effect negative health for so long, but we’re not doing much about it.
HCB: What more needs to be done?
Magzamen: Pediatricians are our first line of defense here. Lead screening is mandatory for children enrolled in Medicaid at first- and second-year checkups, but this is an unfunded mandate. Recent data suggests that about one-third of parents who go in for a well-child check-up spend 10 minutes or less with the doctor. These encounters are so important because lead screening data performed at the check-up are provided to state Childhood Lead Poisoning Prevention Programs, where trends in prevalence and the range of blood lead levels can be tracked over time and space, so we have a better idea of the scope of the problem, and possible efforts to mitigate exposures.
These kids aren’t in school yet, and on average, they don’t have high enough levels to have seizures or other physical signs of extreme lead poisoning, but they do have levels that relate to poor educational outcomes in schools. We need to support efforts to have pediatricians keep testing and keep surveying to make sure that policy-makers know this issue is not going away.
HCB: What can be done to prevent exposure in the first place?
Magzamen: The trick is really to get the lead out of the environment, not only in homes but also in the soil. Lead is often referred to as a legacy pollutant; we haven’t used lead in gas or house paint since the 1970s, but it is a persistent, heavy metal that remains in our environment. Generally, lead exposure has been seen as an inner-city problem or a low-income problem, and this population doesn’t have enough political capital to mitigate exposures. This is a power and environmental justice issue.