Lead exposure persists among children of color and low-income families despite decade of progress

The good news arrived wrapped in a caveat. Over the past decade, blood lead levels in American children have fallen—a genuine public health victory built on decades of work to strip lead from gasoline, paint, and the everyday infrastructure of childhood. But when researchers at Harvard and the University of Pennsylvania dug into state-level data, they found a story the national numbers had been quietly hiding: children of color and children from low-income families are still breathing, drinking, and living with lead at rates that far outpace their white and wealthier peers.

The study, published in the American Journal of Public Health, analyzed blood lead trends from the National Health and Nutrition Examination Survey alongside detailed records from seven states—Connecticut, Delaware, Illinois, Indiana, Massachusetts, Pennsylvania, and South Dakota—that actually track exposure by race, ethnicity, and income. The national data showed no disparities. The state data told a different story entirely. Children in older, poorly maintained housing, disproportionately occupied by families of color, carried higher lead burdens. The exposure was not accidental or random. It was structural, generational, and ongoing.

Mary Jean Brown, an adjunct assistant professor at Harvard Chan School and former chief of lead poisoning prevention at the Centers for Disease Control and Prevention, put it plainly: the national narrative of success obscures a local reality where too many children still face dangerous exposure. The problem is not just the lead that settled into walls and soil decades ago. New sources have emerged—lead in imported spices, in certain cosmetics, in traditional medicines and cookware—creating fresh pathways of exposure that compound the old ones. These newer sources hit hardest in communities already burdened by aging housing stock and limited resources for remediation.

The stakes are not abstract. Lead damages the developing brain. It narrows attention, disrupts learning, shapes behavior in ways that ripple through childhood and into adulthood. No level of lead in a child's blood is safe. When exposure clusters by race and income, the damage becomes not just a health problem but an equity problem—a mechanism by which inequality gets written into neural development.

Then, in October 2025, the Trump administration shut down NHANES. The program had run continuously since 1971, five decades of data that documented America's slow climb out of the lead crisis. The most recent collection cycle, from 2021 to 2023, had not captured enough children to reveal the disparities this new study uncovered. Now, with the surveillance system dismantled, the ability to track where lead exposure is happening and who it is hitting hardest has been severely compromised. Mark Mitchell, health director for Hartford and a co-author of the study, was direct about what was lost: without NHANES, without expanded state-level data collection, the country loses its ability to see the problem clearly, let alone solve it.

The researchers called for restoration and expansion of the monitoring infrastructure, for states to collect and publish data disaggregated by race and income, and for a comprehensive federal effort to eliminate all remaining sources of lead. The work of the past forty years proved it could be done. But that work was never finished. It was only ever paused—and now, for the most vulnerable children, the pause may be becoming permanent.