When we calculated the lead exposure risk of every census tract in America, one major finding stuck out: The vast majority of areas at risk are in urban areas. And health officials generally cite deteriorated lead-based paint in the home — not lead in pipes — as the leading source of lead exposure, which is why relatively inexpensive housing policies can work to reduce incidences of lead poisoning.
We found that 92 percent of the census tracts most at risk are located in urban areas. In some, like New York and Chicago, about 20 percent of census tracts have the highest risk score. In smaller metro areas with populations under 2 million, like Cleveland and Milwaukee, more than 30 percent of census tracts have the highest risk score.
Urban areas with greater risk of lead exposure were not limited to one geographical region. The Midwest, Atlantic Seaboard, and South all have some metro regions in which more than 15 percent of the census tracts had a lead exposure risk of 10 — the highest possible risk level.
Only Western metro areas seem to consistently have lower lead risk. Several metro centers in the South, especially within Florida, also have lower levels of risk.
For instance, in the San Diego metro area, only 1.8 percent of census tracts have a lead exposure risk of 10. In the Baltimore metro area, which is roughly comparable in population, more than 20 percent do.
Two reasons lead is a problem in cities
Although the well-publicized crisis in Flint, Michigan, happened after the city switched to a new, cheaper water source contaminated with lead, health officials generally cite deteriorated lead-based paint in homes or residual lead in soil from gasoline emissions as the two major sources of lead exposure. Both of these factors are far more prevalent in urban and former industrial areas.
In fact, the Pennsylvania Department of Health acknowledged in a 2014 report that the primary source for childhood lead poisoning in the state is lead-based paint in homes. (According to 2010 census data, Pennsylvania is fourth in the nation for housing units built before 1978 — when commercial lead paint was banned.)
Many community activists and experts have argued for years that the most effective way to prevent lead poisoning is to target individual homes for the removal of lead hazards.
House-by-house lead treatment is the way to go, but getting funding can be difficult
David Jacobs, a scientist at the National Center for Healthy Housing, said we need to be tracking houses with known lead risks. That's because most of the intervention work related to lead poisoning is currently happening after a child is diagnosed with elevated blood lead levels and the damage is already done, as the effects of lead are irreversible. "We already know where the old houses and poverty areas are," said Jacobs. "The problem is there is huge variability from unit to unit. We need a housing specific approach."
Some organizations like Isles, a community development and environmental organization in Trenton, New Jersey, are working hard to fill the gap Jacobs describes. Started in 1981, Isles offers services ranging from environmental job training to environmental health assessments of Trenton homes.
Peter Rose, the managing director of Isles, said that lead has been at the center of the organization's work because it is the most dangerous substance they confront in healthy home assessments.
But he is frustrated by the lack of funding available to Isles and other advocacy organizations seeking to do lead remediation in homes. "There is very little that we can do for folks other than teach them how to protect themselves," he said. Isles helps residents identify peeling paint and works to get landlords to help fix existing problems.
Isles offers free tests to detect lead, but says that because of a lack of funds, most remediation efforts don't go beyond fixing peeling paint or trying to have the landlord address the issue.
Rose estimates that most remediation efforts would only cost between $5,000 and $10,000, but funds specifically earmarked for lead remediation programs in New Jersey have been spent in other ways. In 2015 the state was found to have diverted $50 million from its Lead Hazard Control Assistance Fund to instead pay for routine state bills and salaries.
"It is affecting us," said Rose. "There is no kind of line item that says how much it costs to treat lead-poisoned children in New Jersey. We're using our children as lead tests."
Rhode Island showed that relatively inexpensive lead policies can help
In Rhode Island, two housing policies were implemented in 1997 that required landlords to ensure all rental properties were free of lead hazards.
The first required all landlords in the state to obtain "lead-safe certificates" in order to rent their properties. Rhode Island provided landlords with information and training on how to reduce lead hazards in the home. While few resources were dedicated to enforcement, from 1997 to 2010 the total number of lead-safe certificates issued to landlords increased from 333 to more than 41,000.
The second required owners of any building in which a child had tested positive for elevated blood lead to mitigate lead hazards in the child's home or face prosecution by the state attorney general.
A team of researchers examined whether these policies reduced children's blood lead levels. They were mainly interested in examining racial inequality in lead exposure and how it impacts the black-white educational achievement gap.
What they found was that neighborhoods with the greatest share of old housing and higher initial levels of lead in children's blood experienced the biggest increase in new lead-safe certificates. They also had the biggest reductions in lead in children's blood.
The researchers also found that these housing policies disproportionately improved the quality of life for black children. The racial disparity in test scores fell from 9.2 points for those born in 1997 to 6.3 for those born in 2004, and the gap in elevated blood levels fell from 2.2 to 0.9.
Furthermore, the researchers found that these lead remediation programs were relatively inexpensive. Rhode Island spent $500,000 on these two policies annually, meaning that for the eight years of the study, these interventions cost the state of Rhode Island roughly $4 million, which is a fraction of the roughly $3 billion Rhode Island allocates to health and human services annually.