Harmful lead exposure from air, water, and soil impacts the well-being of 151 million Americans.
A new study calculates that exposure to car exhaust from leaded gas during childhood altered the balance of mental health in the U.S.population, making generations of Americans more depressed, anxious, inattentive, or hyperactive.The research estimates that 151 million cases of psychiatric disorder over the past 75 years have resulted from American children’s exposure to lead.
The findings, from Aaron Reuben, a postdoctoral scholar in neuropsychology at Duke University, and colleagues at Florida State University, suggest that Americans born before 1996 experienced significantly higher rates of mental health problems due to lead exposure, likely leading to changes in personality that would hinder their success and resilience in life.
Lead’s toxicity and Its Long-Term Effects
Lead is neurotoxic and can erode brain cells and alter brain function after it enters the body. Health experts assert that there is no safe level of exposure at any point in life. Young children are especially vulnerable to lead’s ability to impair brain progress and alter brain health. Regrettably, our brains are ill-equipped to fend off lead toxicity at any age.
As water systems in older american cities still contain lead pipes, the EPA issued regulations in October that mandate cities to identify and replace lead plumbing within 10 years, allocating $2.6 billion for this initiative. Earlier this year, the EPA also reduced the level of lead in soil that it considers hazardous, resulting in an estimated
Over the past century, lead was used in paint, pipes, solder, and, most disastrously, automotive fuel.Numerous studies have linked lead exposure to neurodevelopmental and mental health problems, particularly conduct disorder, attention-deficit/hyperactivity disorder, and depression. However, it has not been clear how widespread lead-linked mental illness symptoms were until now.
To address the complex question of how leaded gas use for more than 75 years may have impacted human psychology, reuben and his co-authors Michael McFarland and Mathew Hauer, both professors of sociology at Florida State University, analyzed publicly available nationwide data.
Using ancient data on U.S.childhood blood-lead levels, leaded-gas use, and population statistics, thay calculated the likely lifelong burden of lead exposure carried by every American alive in 2015. From this data, they estimated lead’s negative impact on mental health and personality by calculating “mental illness points” gained from leaded gas exposure as a proxy for its harmful public health impact.
Widespread psychological Impacts
“We saw very significant shifts in mental health across generations of Americans,” Hauer noted. “This means many more peopel experienced psychiatric issues than would have occurred if we had never added lead to gasoline.” Lead exposure resulted in higher rates of diagnosable mental disorders, such as depression and anxiety, as well as an increase in individuals experiencing lower levels of distress that would impair their quality of life.
As of 2015, over 170 million americans (more than half the U.S. population) had clinically concerning levels of lead in their blood as children, likely resulting in lower IQs, more mental health issues, and increased risks for other long-term health impairments, such as elevated cardiovascular disease.
Leaded gasoline consumption surged in the early 1960s and peaked in the 1970s. consequently, Reuben and his colleagues discovered that essentially everyone born during these two decades was likely to have been exposed to dangerous levels of lead from car exhaust.
Generation X (1965-1980), experienced the greatest mental health declines.
“We are beginning to understand that lead exposures from the past—even those from decades ago—can affect our health today,” Reuben said. “Our goal moving forward will be to better comprehend the role that lead has played in our country’s health and to ensure we protect today’s children from new lead exposures wherever they occur.”
Reference: “contribution of childhood lead exposure to psychopathology in the US population over the past 75 years” by Michael J. McFarland, Aaron Reuben, and Matt Hauer, 4 December 2024, Journal of Child Psychology and Psychiatry.
DOI: 10.1111/jcpp.14072
The study was funded by the National Institute of Environmental Health Sciences.
What are the long-term mental health effects of lead exposure in children?
Interview: the Lasting Impact of Lead Exposure on Mental Health
Editor (Time.news): Welcome,Dr. Aaron Reuben. Your recent study linking lead exposure to mental health issues has shaken the foundations of public health understanding in America. Can you summarize your findings for our readers?
Dr.Aaron reuben: Thank you for having me! Our study highlights a troubling reality: exposure to leaded gasoline during childhood has significantly influenced mental health across generations. We estimate that approximately 151 million psychiatric cases over the past 75 years are connected to this exposure, especially affecting individuals born before 1996.
Editor: That’s a staggering number. What specific mental health issues are linked to lead exposure?
Dr. Reuben: We found that lead exposure correlates with higher rates of depression,anxiety,attention disorders,and even personality changes in affected individuals. This has profound implications for societal functioning, as these mental health challenges can hinder success and resilience in various aspects of life.
Editor: It’s alarming to think that something as ubiquitous as lead in gasoline could have such a lasting impact. Could you explain how lead affects the brain?
Dr. Reuben: Absolutely. Lead is a neurotoxin that can irreversibly damage brain cells and alter brain function. It’s particularly harmful to young children, whose brains are still developing. the neurotoxic effects can lead to a cascade of issues, disrupting cognitive functions and emotional regulation.
Editor: Your research indicates that millions are still affected today. How are current public health policies addressing these risks?
Dr. Reuben: Recent actions, like the EPA’s push to replace lead pipes and reduce hazardous lead levels in soil, are steps in the right direction.They’ve allocated substantial funding for these initiatives, which is crucial. However, many old infrastructures still contain lead, and awareness about lead toxicity must improve to protect future generations.
Editor: Given the historical context and ongoing risks, what should parents and communities be aware of regarding lead exposure today?
Dr. Reuben: Parents should be proactive about testing their homes for lead, particularly if their buildings were constructed before the mid-1990s.Communities must advocate for safer environments, including clean water and less lead in soil. Education on the dangers of lead exposure is critical – it truly can have lifelong consequences.
Editor: It’s clear that addressing this issue goes beyond individual households. What role does policy change play in mitigating lead exposure, especially for future generations?
dr. Reuben: Strong oversight and legislation are essential. Policies must be rigorous regarding the regulation and reduction of lead in all forms—water, soil, and air. Additionally, public health campaigns bringing attention to lead’s risks would empower communities to take action. effectively, it’s about ensuring safe environments for present and future generations.
Editor: Lastly, what message do you hope readers take away from your research?
Dr. Reuben: I hope readers come to understand that lead exposure is more than a historical issue—it’s a pressing public health concern that continues to effect millions. Recognizing and addressing lead’s impact is crucial for fostering healthier, more resilient communities. Together, we can work towards a future where lead poisoning is a thing of the past.
Editor: Thank you for sharing your insights with us, Dr. Reuben. Your work sheds light on an urgent public health challenge that deserves our attention.
Dr. Reuben: Thank you for having me! It’s essential to keep the conversation going about mental health and its environmental determinants.