Posts

Columbia study: Air pollution can lead to ADHD in kids

A study at Columbia University indicates that children who were exposed to high levels of air pollution from vehicles while they were in the womb were five times more likely to develop symptoms associated with attention-deficit disorder later in life.

As Scientific American reports:

The study adds to earlier evidence that mothers’ exposures to polycyclic aromatic hydrocarbons (PAHs), which are emitted by the burning of fossil fuels and other organic materials, are linked to children’s behavioral problems associated with Attention Deficit Hyperactivity Disorder (ADHD).

About 10 percent of U.S. children are diagnosed with ADHD, which can impair classroom performance, as well as lead to “risky behaviors and lower earnings in adulthood,” the Columbia researchers wrote.

The study, led by Frederica Perera, an environmental health scientist at the school’s Mailman School of Public Health, looked at the children of 233 African-American and Dominican women in New York City.

More from SciAmerican:

They measured the amount of benzo[a]pyrene bound to DNA – a biological marker for PAHs – in the mothers’ blood at the time of birth. Forty-two percent had detectable levels in their blood.

When the children were about 9 years old, parents filled out a questionnaire commonly used to screen for ADHD behavior problems. The researchers found that children whose mothers had the highest amounts of the PAH at the time of birth were five times more likely to show more behaviors associated with inattention than children whose mothers had the lowest levels. They were three times more likely to exhibit more total behaviors (inattention, hyperactivity and impulsivity) associated with ADHD.

Read more on the Columbia website.

Yet more evidence that air pollution harms health

Research announced this week at the University of Pittsburgh is only the latest to suggest a link between air pollution and a higher risk of children developing autism.

Motor vehicles – cars, trucks and SUVs – account for about half the air pollution in the United States, the EPA says, with much of the rest coming from industrial sources and coal-fired power plants.

Smog levels are much worse in urban areas than rural ones: According to the American Lung Association’s State of the Air 2014 report, 47 percent of the nation — 147.6 million people — live in places where pollution levels make it dangerous to breathe.

Air toxics, as they’re called, can contribute to asthma and other respiratory problems; heart disease. Experts think that these toxics can have a particularly devastating impact on babies when they’re in the womb, and when the children are very young.

Although much of the science on these effects has only been conducted in the past decade, a 2008 report at UCLA’s Institute of the Environment and Sustainability says: “Recently this research has begun to focus on one specific source of modern-day air pollution – traffic exhaust.”

The study, led by Dr. Beate Ritz, goes on:

“These studies largely focused on potential mortality impacts of airborne particulate matter small enough to penetrate into the human respiratory tract, referred to as PM10 (particulate matter less than 10 microns in aerodynamic diameter) and more recently have examined PM2.5, even smaller size particles which can penetrate deep into the lung. Most findings from this research indicated infants living in areas with high levels of these types of particulate matter had a greater risk of mortality during the first year of life, particularly from respiratory causes.”

Autism Spectrum Disorder (ASD), a neurological disorder whose symptoms can range from having trouble fitting in with peers to repetitive behaviors to a complete lack of communication and even seizures, now affects an estimated 1 in every 68 U.S. children, a 30 percent increase since 2012. Little is still known about the causes, but many experts believe genetics or environmental exposures, or a combination, are to blame.

The University of Pittsburgh report, led by a health professor of epidemiology named Evelyn Talbott, found that children who were somewhere on the autism spectrum were 1.4 to 2 times as likely to have been exposed to air pollution during their mothers’ pregnancies, compared with children who did not have an ASD. The affected children showed higher levels of styrene, cyanide and chromium.

Irva Hertz-Picciotto, a UC Davis researcher not affiliated with the Pitt study, told the Pittsburgh Post-Gazette that this and other studies like it “do suggest some kind of a link where a family who has children with autism were living usually closer to areas with higher [air toxic] measurements.”

In Utah, where some regions have very poor air quality in wintertime, the incidence of autism is 1 in 47 children, far higher than the national average. Earlier this year, a Harvard study showed that “exposure in the womb to diesel, lead, manganese, mercury, methylene chloride and an overall measure of metals was ‘significantly associated with autism spectrum disorder,’ with the highest association from exposure to diesel exhaust,” according to a story in the Provo Herald Extra.

Given the significant adverse health effects that result from gasoline when it’s combusted inside engines, it makes sense to incorporate cleaner-burning fuels into the nation’s fleet of vehicles. The EPA says as much, saying replacement fuels, including “natural gas, propane, methanol, ethanol, electricity, and biodiesel” can be ” cleaner than gasoline or diesel and can reduce emissions of harmful pollutants.”

(Photo: Los Angeles air, via Shutterstock)