On a May 2023 episode of his podcast, former Tennessee Gov. Phil Bredesen asked renowned criminal justice economist Jennifer Doleac for her top suggestions for improving public safety.
Doleac gave an unconventional answer: Protect young kids from lead.
“Exposure to lead … when you’re really young, it changes your brain development. Fifteen years later, we’re going to see much higher rates of juvenile delinquency (and) suspension from school,” Doleac said. “If it were up to me — if I had a magic wand — I would spend a whole lot of money on getting lead out of the environment.”
In 2023, 389 kids in Shelby County — and 2,400 statewide — tested positive for lead poisoning, according to state data. That’s likely an undercount, since so few children are tested.
Public safety dominates the civic conversation in Memphis, which set a homicide record in 2023 but has experienced a decline in overall crime in recent months. While most criminal justice debate here — and proposed legislation from state legislators — focuses on punishment, local lead remediation experts lament that their work isn’t taken seriously as a public safety solution despite the evidence.
The research is clear: Lead poisoning damages the part of the brain responsible for self-control. While this damage is usually mild, reducing that internal control increases the risk that lead-poisoned children will engage in impulsive behavior, including criminal activity as teens and adults, experts say. Dozens of studies have linked lead exposure to increased arrests.
“(There is) clear evidence that lead pollution increases crime,” said Anthony Higney, co-author of a meta-analysis of about 30 studies on the topic. The analysis found that declining lead exposure probably accounted for roughly 15% of America’s decline in homicides from 1989 to 2014.
A growing body of research — using different methods and types of data — has made lead’s public safety effects difficult to dispute. Experts who have conducted some of these studies told MLK50 how and where the toxin likely increases crime and why local leaders should take notice.
How does lead affect behavior?
Lead damages children’s brains by deceiving them.
It mimics calcium — a mineral necessary for the brain’s growth. When kids under 6 ingest lead dust from old lead paint or other sources, their bodies can accidentally insert a bug into the brain’s electrical system.
Because of this, the brains of lead-exposed children, on average, look different from their peers (smaller in key regions) in images captured later in life.
Lead particularly affects the brain’s frontal lobe, which is responsible for self-control. People with less volume in the front of their brains, for instance, are at greater risk for behavioral disorders.
This doesn’t mean that every child who ingests lead will struggle with controlling their impulses, said John Paul Wright, a University of Cincinnati professor who has researched lead’s link to crime for decades. Lead affects kids in various and unpredictable ways. But, when studying large cohorts of children, it has become clear that the toxin can alter behavior.
If you have kids under 6 who either live in or regularly visit a home, daycare or preschool built before 1978, please have them tested for lead poisoning. To schedule a free test, call the Shelby County Health Department at 901-222-9582 or contact your child’s pediatrician. If you’re not sure when your home was built, it is usually listed on the Shelby County Assessor of Property website and Realtor.com.
Kevin Schnepel, an economist studying crime at Canada’s Simon Fraser University, said it’s easy to see how a decrease in self-control could increase the chances a child would be arrested later in life, as much criminal behavior stems from impulses, not rational thinking. For example, domestic violence and homicide are often a result of someone not being able to control their anger.
Studies have connected lead to violent crimes and property crimes. A 2021 study in Cincinnati by Wright and his colleagues found a moderate (5 micrograms per deciliter) increase in childhood blood lead levels corresponded with a 5% to 6% increase in total arrests — with a rise in arrests for both violent and property-related crimes.
Experts studying lead’s effects on juvenile delinquency have found larger effects. A 2002 study by researchers at the University of Pittsburgh and Carnegie Mellon University compared the lead levels of youth in Pittsburgh’s juvenile justice system with other city high schoolers. After adjusting for other variables — such as parental education and neighborhood crime rate — the study found the youth convicted in juvenile court were four times more likely to have elevated levels of lead. And a 2019 study by professors at Brown University and Princeton University found that elevated blood lead levels in young boys place them at an almost 60% higher probability of eventually facing juvenile detention.
Lead’s effect on impulse control is the primary way researchers think lead influences crime and juvenile delinquency. But it’s not the only pathway.
Students with elevated levels of lead are more frequently labeled “substantially below proficient” at school and are less likely to graduate high school.
Because of the strong link between education and crime, it’s possible that lead’s effect on crime is a direct result of the toxin’s effect on education, Higney said. Kids who learn less in school have fewer job opportunities, and people with fewer opportunities to earn money are more likely to turn to crime.
Bearing the brunt of lead’s burden
In the 1970s, the U.S. began phasing out leaded gasoline and banned lead paint.
Neighborhoods built before then bear the brunt of lead’s dangers, since lead paint remains in many homes — often hiding behind newer paint but easily exposed through friction. In many cities — including Memphis — these older neighborhoods are primarily occupied by Black and brown residents, thanks to white flight and segregation. The map below shows which Memphis ZIPs contain the most homes built before 1980, according to census data.
A 2016 study by Harvard researchers found extraordinary levels of lead in predominantly Black Chicago neighborhoods compared to white ones. The difference exceeded what would be expected based on the neighborhoods’ income levels and the homes’ ages.
“Lead toxicity is a source of ecological inequity by race and a pathway through which racial inequality literally gets into the body,” the authors wrote.
If lead poisoning affected more white, wealthy residents, the government would have likely made lead removal a priority, said Alix Winter, a co-author of the Harvard study. But, the neighborhoods most at risk are low-income and Black, and U.S. public policy has historically done less to protect such areas from pollutants and other harms.
Winter, who has also studied the lead-crime connection, stressed lead exposure does not predestine any victim to commit crimes.
“It’s not that lead exposure is determinative of anything, but it is harmful and Black people are differentially exposed to that harm,” she said. “And that’s something we should try to remedy.”
Complicating the racial dynamics of the lead-crime connection is the criminalization of Black youth for impulsive behavior typical for their age, such as experimenting with marijuana.
“There’s behavior that people engage in all the time and tends to be criminalized more … among people that are Black,” Winter said.
Joya Hampton-Anderson, an expert on the determinants of health disparities at Emory University, framed the lead-crime link around the concept of wellness. The lead-crime pattern, she said, should be no surprise since the toxin — like other environmental pollutants — affects wellness.
“Crime occurs when people are unwell — mentally unwell, physically unwell,” she said.
Lead’s burden, she said, sits on top of many other ways that historical, structural and environmental racism has harmed the health of Black youth.
Because of these realities, Hampton-Anderson said it’s important for society to avoid racist narratives about Black youth and instead think about crime in Black communities as the result of “the system.”
Removing lead to reduce crime
MLK50 asked the experts how much crime would be reduced if lawmakers took lead remediation more seriously.
Wright said he’s skeptical the U.S. could see the same scale of public safety improvement from lead removal it saw during the 1990s and 2000s.
This is because there is now much less lead in the environment than there used to be. In the late 1970s, the median child under 6 had a blood lead level of 15 micrograms per deciliter — four times the current federal standard for concern, according to the National Center for Health Statistics. By the mid-2000s, that number had dropped to 1.4; today, it stands around 0.6.
“Reducing the amount of exposure to lead (as well as) investing in (other) early life health conditions … are going to be the big anti-crime investments that would yield the biggest long-term benefit.”
Kevin Schnepel, an economist studying crime at Canada’s Simon Fraser University
Elevated blood lead levels used to affect most American children. Now, its effects are — for the most part — concentrated on kids crawling around in particularly hazardous homes or daycare facilities.
In especially old neighborhoods, Wright said, lead abatement could still pay significant public safety dividends. Still, he disagrees with Doleac that it should be considered the top long-term crime reduction strategy.
Higney was hesitant to guess the scale but said he’s extremely confident removing more lead would decrease crime — while simultaneously boosting education and public health. (Studies have shown lead exposure can increase victims’ blood pressure, damage their kidneys and put them at greater risk of developing mental illness.)
Schnepel largely agreed with Doleac’s analysis. The strategies that have been shown to best reduce crime, he said, are those that improve the environment in which kids spend their first few years — the most important time for brain development.
“Reducing the amount of exposure to lead (as well as) investing in (other) early life health conditions … are going to be the big anti-crime investments that would yield the biggest long-term benefit,” he said.
Lead remediation officials in Shelby County told MLK50 they’ve struggled to get local leaders’ attention.
In 2022, Anita Tate, who runs the Shelby County Lead Hazard Control Program, attended a public safety forum that Memphis Police Chief Cerelyn “C.J.” Davis attended. She asked Davis if she’d considered the role lead could play in the city’s crime problems.
Davis brushed the question off, Tate said.
MPD spokesman Lt. Bill Kaiser told MLK50 the police department is “unaware of any research conducted by either the Centers for Disease Control or the Environmental Protection Agency concerning a link between lead poisoning and the crime that occurs within the city of Memphis. Therefore, Chief Davis would be unable to give an informed response.”
Although there don’t seem to be specific studies that examine the link between lead and crime in Memphis, the CDC does link criminal behavior to lead exposure.
That same year, Tate compiled a bundle of lead-crime research and mailed it to the Memphis Shelby County Crime Commission, pleading with them to meet with her.
She never heard back. Crime Commission president Bill Gibbons told MLK50 he didn’t remember receiving it.
Jacob Steimer is a corps member with Report for America, a national service program that places journalists in local newsrooms. Email him at Jacob.Steimer@mlk50.com
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