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Originally published May 31 2015

Why cities make people stupid: Air pollution significantly reduces children's IQ, study finds

by Julie Wilson staff writer

(NaturalNews) Metropolitan cities continue to swell across the U.S. as millions flock to densely populated regions seeking employment and hoping for a better quality of life. As urban life continues to grow more popular (especially in the New York metropolitan area), so does the risk of developing various diseases caused by pollutants that are highly concentrated in large cities, some of which include respiratory complications and irreversible damage in unborn children.

The World Health Organization estimates that 1.2 million people are killed annually due to urban air pollution, a significant portion of which is generated by industry, energy production and vehicles.

While previous studies have linked urban air pollution to type 2 diabetes and increased blood sugar levels in pregnant women, among other ailments, new research suggests that poor air quality might also be responsible for reducing children's IQs, affecting their ability to learn and access information.

Exposure to air pollution and economic hardship lowers kids' IQs, making it more difficult for them to access and process information

Referred to as a "first-of-its-kind-study," the new report from Columbia University's Mailman School of Public Health concludes that children born to mothers experiencing economic hardship who were exposed to high levels of urban air pollution suffered from reduced IQs, imposing an obvious hardship beginning at birth.

"The findings are a concern because, as has been shown with lead [poisoning], even a modest decrease in IQ can impact lifetime earnings," researchers wrote.

One specific type of air pollution proved to be the most deadly. Unborn children exposed to polycyclic aromatic hydrocarbons, or PAH, scored much lower on IQ tests at age five compared with children born to wealthier families who were less exposed to air pollutants, according to the report, which was published in the medical journal Neurotoxicology and Teratology.

"PAH are ubiquitous in the environment from emissions from motor vehicles, oil, and coal-burning for home heating and power generation, tobacco smoke, and other combustion sources."

Unborn children exposed to PAH showed developmental delay beginning at age three

Beginning when their mothers were pregnant, researchers tracked the development of 276 minority children from Harlem, Washington Heights and the South Bronx for seven years, reports the New York Post.

At age seven, the children who were less privileged and coincidentally raised in areas with more air pollution "scored lower on tests of full scale IQ, perceptual reasoning, and working memory" compared to children who did not.

Responsible for accessing information, working memory is crucial in young children as it plays a pivotal role in following directions, focus and concentration as well as learning new subjects such as math and reading.

Scientists wrote:

The findings add to other evidence that socioeconomic disadvantage can increase the adverse effects of toxic physical 'stressors' like air pollutants. The present results suggest the need for a multifaceted approach to reduce PAH exposure and alleviate material hardship in order to protect the developing fetus and young child.

Early exposure to PAH might also cause anxiety and depression in young children

Prenatal exposure to PAH during gestation was also found to cause "development delay at age 3, reduced verbal and full scale IQ at age 5, and symptoms of anxiety and depression at age 7," according to the report.

"The findings support policy interventions to reduce air pollution exposure in urban areas as well as programs to screen women early in pregnancy to identify those in need of psychological or material support," said the report's lead author Frederica Perera, who is also the director of the Columbia Center for Children's Environmental Health.

"This report adds to the growing literature on the vulnerability of the developing fetus and young child to the toxic effects of environmental pollutants," researchers concluded.

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