Lead contamination in soil tracked inside homes can cause dangerous indoor lead dust levels even in residences with no interior lead-based paint, according to researchers with the Rutgers Environmental, Occupational and Health Sciences Institute in collaboration with community scientists from the East Trenton Collaborative.
The study , published in the Journal of Exposure Science & Environmental Epidemiology, was conducted in the neighborhood of East Trenton, in Trenton, N.J., which the U.S. Environmental Protection Agency (EPA) added to the Superfund National Priorities List in 2025 after determining there was lead contamination in soil from 19th-century pottery manufacturing plants.
They found 86% of 242 bare surface soil samples collected exceeded the EPA's 200 parts per million residential soil lead hazard level and nearly 94% exceeded screening levels for multiple sources of lead exposure. "This is especially concerning because all samples were collected from bare soil at the surface, which is the most likely to be accessed by children or tracked into homes," said Sean Stratton, a recent Rutgers School of Public Health PhD graduate and lead author of the study.
In homes without any interior lead-based paint, 80% of floor dust samples exceeded the safety threshold. "The research shows no significant difference in interior floor lead levels between homes with lead-based paint and those without, which confirms that outdoor soil tracking is a cause of indoor lead dust," he said.
According to the EPA , lead poisoning can affect brain development in young children, damage vital organs and cause lasting behavioral and neurological damage. Partnering with the East Trenton Collaborative, a community organizing and development initiative in East Trenton's North Ward, Rutgers researchers recruited and trained residents to collect soil samples from 122 homes in the designated area. From these, researchers used X-ray fluorescence analyzers to determine lead-based paint levels and then collected interior dust samples from floors, windowsills and window wells in 42 homes.
Indoor lead exposure in the United States historically has been attributed to flaking lead-based paint, which was used in houses before 1978, the year that the federal government banned consumer uses of lead-based paint. However, researchers noted, this study shows that the age of a house doesn't mean lead dust is not present.
"The findings are significant because the thought was if there was lead in the dust, it's coming from the paint on the walls and if a house was built after 1978 there was nothing to worry about, but that's not always true," said Brian Buckley, director of research with the Rutgers Environmental, Occupational and Health Sciences Institute and an author of the study.
The study builds upon the institute researchers' previous collaboration with the Newark Water Coalition to engage community scientists to distribute 500 water testing kits to residents to test the efficacy of water flushing methods to reduce lead in the water system.
That study, published earlier this year in the Journal of Water & Health, revealed that lead was present across the surveyed homes and that flushing taps didn't eliminate the danger. The experience working with the community and the results of the study helped the researchers establish trust in the East Trenton community, whose members approached them to test the soil and allowed them access to residences they otherwise might not have had.
"Our collaborative research in Newark demonstrated the power of citizen-led scientific data collection, which helped us engage the community in East Trenton to assist in the study," said Stratton. "By demonstrating how members of the community were integral to understanding the environmental health threats in their neighborhood — and how it empowered citizens — it helped us engage with another community."
Other Rutgers authors include Adrienne Ettinger and Zorimar Rivera-Núñez. Shereyl Snider, East Trenton Collaborative's community organizer, was a co-author.
