What the research says about the link between lead pollution and crime

Pollution from lead battery recycling has led to widespread contamination

Many small-scale operations worldwide remain unregulated, bypassing environmental regulations and causing increasing health threats, primarily to children. A 2020 report by UNICEF found that one-third of the world's children are being poisoned by lead from recycled batteries, among other sources.

Why it's so hard to end the use of toxic lead

Lead was one of the earliest metals mined on Earth, desired for its soft malleability and used in cosmetics, pipework, gasoline, and more. But even though researchers demonstrated its toxicity in the 20th century, much of the world still uses it.

Chronic exposure to traffic noise is associated with a higher risk of Parkinson's disease.

Murder rates spiked in the US after COVID-19, and then declined in 2023

Criminologist and former investigator Jillian Peterson says whether a murder is solved in the US is nearly up to the flip of a coin, with the clearance rate for murder cases being about 50%. The US, which has more guns than citizens, has about roughly five gun homicides per 100,000 residents, resulting in the 28th-highest rate of deaths from gun violence compared to the rest of the world.

Studies show immigrants commit crimes at lower rates than native-born Americans

Research examining incarceration records and crime data generally finds that immigrants—including undocumented individuals—have lower crime and incarceration rates than US-born citizens, though measurement is limited by gaps in national data on immigration status.

Some data links schizophrenia to older paternal age and birth complications

Yet both associations are not yet considered firm enough to definitively be causative. Schizophrenia is a multi-causal syndrome and a mixture of factors, including genetics, are widely believed to be behind its development.

Review the health effects of living near oil refineries, including increased respiratory risks

An analysis of 54 studies published between 1977 and 2024 in 15 international regions found evidence that proximity to refineries increased the risks of leukemia, asthma, bronchitis, and respiratory symptoms. Several studies also identified worse cardiovascular function in children and adults living near refineries, alongside other acute and chronic health impacts.

Risk factors linked with ASD include older parents, preterm births, and toxic prenatal exposures

Though researchers agree that there is a strong genetic component to ASD development, certain environmental factors heighten that risk, with studies suggesting older parents, premature birth, maternal obesity, and air pollution exposure in utero all elevate risks of ASD development. There is no connection between receiving vaccines and ASD development.

Autoimmune disease prevalence and incidence are on the rise—but no one knows why

Researchers theorize that environmental factors, including shifts to less healthy diets, air pollution, infections, stress, climate change, and exposures to xenobiotics—substances like pesticides, plastics, and toxins that incite immune responses—may all be fueling epigenetic changes to our bodies that make people's immune responses go awry.

Volatile chemical contamination can last in burn areas long after urban wildfires

Lead, arsenic, asbestos, and other chemicals have been found trapped in smoke-exposed rugs, couches, pillows, and other furniture that appeared otherwise undamaged from the 2025 LA wildfires. The gradual release of these substances has produced dangerous indoor air concentrations and contributed to increased emergency room visits and abnormal blood tests.

Consuming true crime media can increase stress and anxiety and create a false sense of danger.

Ultraprocessed foods are linked with a 58% elevated risk of developing dementia.

Traumatic childhood experiences heighten the risk of developing schizophrenia

Clinically termed as "adverse childhood experiences," events such as physical or mental abuse or the death of loved ones have repeatedly been linked to an increase in rates of developing schizophrenia later in life. The reasons behind this link remain under investigation.

What happened to thousands of teens from the 1990s?

Scientists followed thousands of teenagers from 1997 into their 30s, cataloging their adverse experiences along the way via nearly three decades of interviews. Teens who grew up dealing with poverty, uninvolved parents, and other childhood stressors and traumas racked up an ACE score. These adverse childhood experiences have lifelong impacts on one's health, relationships, financial security, and "pretty much everything else," making them more likely to suffer premature death.

Hearing loss is linked with brain volume reductions

The brain looks different as a result of hearing loss, with reductions in brain volume overall and in specific areas, and these changes are hypothesized to impact cognition. Exactly why hearing loss alters cognition is an active area of research, but theories include that the elevated cognitive load of straining to hear affects brain power available for thinking and memory and that hearing loss leads to social isolation which boosts dementia risk.

Alzheimer's in the United States is most prevalent in the South and the East.

Supplements often have issues with impurities, toxins, and inaccurate labels

Consumer Reports' tests of more than 20 supplement powders and shakes in 2025 found that more than two-thirds of them contain unsafe levels of lead. Some contained 10 times the amount of lead that's considered acceptable to ingest in a day. The levels they found, in some cases, were even higher than when they tested the products 15 years earlier.

Repeated head injuries, which may occur in collision sports at the youth, amateur, and professional levels, can lead to CTE and early dementia.

What's with the teen brain, anyway

In this video NIDA explores the intriguing similarities between the processes of brain development and computer programming. This analogy helps us understand why toxic environmental factors like drugs, bullying, or lack of sleep strongly affect a teenager's life The information provided by this video can empower your children or students with information they need make better decisions.

Fertility treatments linked to increased risk of cancer among offspring

Recent research has explored potential links between increased childhood cancer occurrence, particularly leukemia, and assisted reproductive technology (ART). Though some studies have detected this type of association, researchers caution that it remains unclear if ART itself, fertility drugs, underlying infertility of the parents, or other unknown factors may explain any increased cancer numbers among ART-conceived children. Overall, the incidence of cancer in children, regardless of conception method, is very low.

Stress contributes to gray hair because when the body experiences stress, the sympathetic nervous system releases specific hormones that influence pigment-producing cells.

Research shows that microplastics and nanoplastics can accumulate in major arteries, and patients with these deposits are significantly more likely to suffer heart attacks, strokes, or death.

Retired professional soccer players are showing signs of potential neurological impacts in midlife, according to a study presented at the July 2026 Alzheimer's Association International Conference in London.

Grip strength, how firmly and securely you can hold onto things, predicts death better than blood pressure

Listen to an in-depth conversation on the links between Parkinson's disease and herbicide exposure.

Explore options for recycling batteries

Improper battery disposal can lead to fires and the leaching of harmful chemicals and toxic materials into local soil and water systems. Although many batteries contain metals that can be recycled with less energy than it takes to produce them, variability in regulations across municipalities and states can complicate efforts. (Some readers may experience a paywall.)

Can the gut microbiome drive addiction?

New research suggests an imbalance of gut microorganisms may influence the likelihood of addiction and addictive behaviors by increasing the severity of withdrawal symptoms, triggering brain inflammation in regions of impulse control, and more.

How race science influences breast cancer research

Despite researchers' and physicians' pushback, race is still used in studies and clinics to categorize human differences in health conditions and treatment responses. This article explores how race has influenced breast cancer research. Considering race as a factor in cancer research, diagnosis, and treatment can lead to racial inequalities. Sociocultural factors, including food access and air pollution, greatly influence health outcomes.

Poor sleep increases the risk of developing Alzheimer's, and a main reason appears to be that the brain disposes of toxic protein buildup during high-quality sleep.

Microplastics are infiltrating the human body with unclear but concerning effects

Scientists have linked microplastics to immune system damage, hormone disruption, inflammatory diseases, and even cancer—yet most of their health impacts remain unknown due to limited research. Studies suggest we ingest about a credit card's worth of plastic weekly.

Explore how close you live to some of the most contaminated places in the US

Known as Superfund sites, these toxic locations undergo long-term cleanup to remove hazardous waste, protect health, and restore land for safe reuse. As of 2025, the EPA lists around 1,300 active Superfund sites on its National Priorities List, with more than 450 cleaned and removed since 1980.

Children of 9/11 Ground Zero responders are suffering from intergenerational trauma similar to what's seen among the children of Holocaust survivors, according to recent research.

Researchers are exploring neural links between Alzheimer's and autism

Recent DNA sequencing and molecular biology studies suggest that similarities in genes, neural circuitry and patterns of disease warrant further exploration to potentially better understand both conditions and how to treat them. (Some users may encounter a paywall.)

How uploading your consumer genetic testing could lead to a distant relative's arrest

This podcast includes a discussion about how law enforcement can compare DNA samples from a crime scene against voluntarily uploaded DNA on consumer genealogy databases to close cases. Investigators can and have cross-referenced a suspect's crime scene DNA with that of a suspect's relatives who happened to have chosen to upload their genetic information to an open-source genealogy database.

Chronic drug use can cause neurological changes in the brain

Neuroscientist Judy Grisel breaks down the biology of addiction, examining how drugs hijack the brain’s natural reward system and create lasting neural changes. The physiological and neurological impacts of chronic drug use require a multifaceted treatment approach.

JJ Schildkraut theorized depression is linked to brain chemical imbalances—in 1965

Schildkraut was one of the first to put forward this idea, which stemmed from lab animal research. A decade later, researchers published the first landmark paper on fluoxetine—better known by trade name Prozac—which increases serotonin levels in the brain.

Stress and the brain

While an acute stress response is a normal bodily function, the effects of chronic stress can be extremely damaging to the human body. This is particularly true with regard to the brain. This article explores the effects of stress on the human brain, including how chronic stress may lead to psychological conditions such as depression and memory loss.

True crime, explained

Tales exploring some of the most grisly and unthinkable crimes have satisfied the public's morbid curiosity for more than a century, and modern podcasting has shot the genre to new heights. Want to learn more about the history of true crime? 1440 has the breakdown here.

Stress can be contagious—and scientists want to learn more about it

Researchers have shown that being around someone who is stressed can trigger a stress response in your body, such as elevated cortisol levels and elevated heart rate. One way this was recently studied was by having people watch stressful activities, like a recorded job interview or solving challenging math problems, and then sampling hormones in observers' spit.

Nearly a quarter of the US's 451 top-ranked podcasts belong to the true crime genre

Perhaps, Pew Research Center proposes, this popularity stems from the fame of "Serial," the 2014 hit series about a 1999 murder in Baltimore. Politics and government is the second top genre. Outside typical genre divides lie series such as fictional radio stories and Dungeons & Dragons podcasts, which account for 12% of top-ranked podcasts.

Analyzing brownfield cleanup to explain why bioremediation aligns with environmental justice

This designation applies to sites contaminated by industrial or commercial activity and that are either underutilized or abandoned. Common in economically disadvantaged communities of color, brownfields pose risks to human health and can be costly to restore. Bioremediation can be a more affordable solution that creates in-demand employment pathways in environmental science, regenerative agriculture, and ecological restoration for community members.

True crime fans can derail lives with misguided accusations

In the wake of four stabbing deaths at the University of Idaho in November 2023, online sleuths, without any supporting evidence, were quick to point accusatory fingers at potential perpetrators. Poring over news reports, social media pages, and internet interactions can reveal viable information that can help solve crimes. Such (sometimes monetizable) behavior can also easily give rise to rumors and threats while impeding official investigations.(Some readers may experience a paywall.)

How reading and writing can lower dementia risk by almost 40%

Research published in 2026 that tracked almost 2,000 older adults for an average of nearly eight years suggests that lifelong exposure to intellectual stimulation, such as learning a language, reading, and writing, can lower dementia risk by as much as 40%.

A pregnant woman's brain sheds gray matter, perhaps explaining 'baby brain.'

Minorities are largely underrepresented in medical research, which compromises our understanding of how conditions and treatments may affect various populations, but recent efforts, like the African Ancestry Neuroscience Research Initiative and new genome research studies, are seeking to close that gap.

The Love Canal disaster exposed the dangers of buried toxic waste

In the late 1970s, residents of Niagara Falls, New York, discovered their neighborhood was built atop 20,000 tons of chemical waste. Leaking toxins caused illness and birth defects, sparking nationwide outrage and leading to the creation of the EPA's Superfund cleanup program in 1980.

How we frame stress—as good or bad—seems to alter how it affects us

This podcast discusses research that indicates stress perception may drastically affect how we respond to it. In research exploring if our stress is presented as diminishing our health versus if we're told it enhances our performance, it will lead to differences in how successful participants are at performing tasks—with the enhancers doing better.

Schizophrenia symptoms, like psychosis, often first emerge among young adults

A combination of genetics, significant brain changes to the frontal cortex, and hormonal changes during young adulthood—late teens to early 30s—result in schizophrenic symptoms often showing up during this period. The stress of life changes at that age may also be a contributing factor.

How epigenetics blurs the line between nature and nurture

An exploration of the study of how behaviors and environment affect the way genes work — and how that complicates the nature-versus-nurture debate.

The Golden State killer case spotlights how genetic testing can affect your—and your relatives'—privacy

Police managed to use consumer DNA test results to close a case 32 years after a killer was believed to have committed at least 12 murders and 50 rapes. Their "smoking gun": They compared a DNA sample from the crime scene to genetic data relatives had shared on an open-source genealogy database. The suspect was caught after investigators explored family trees on this database and connected the dots from over 100 distant relatives who had some percentage of DNA that matched the killer. (Some users may encounter a paywall.)