Some children living in the Big Apple are not only exposed to economic hardships, they are also exposed to high levels of air pollution that causes a significant effect on their IQ and brain development, according to a new study conducted by Columbia University's Children's Environmental Health at the Mailman School of Public Health.

The researchers learned that pregnant mothers and babies, who belong to underprivileged families in New York City, are often highly exposed to PAHs or polycyclic aromatic hydrocarbons, a fast-spreading pollutant that is emitted from gasoline, heating oil and diesel.

For seven years, the researchers kept track of the development of 276 children and their mothers in areas like South Bronx, Washington Heights and Harlem. While pregnant with the children, their mothers were made to carry monitors and were interviewed regularly throughout the study. From birth, the baby's umbilical cords were already examined for presence of PAHs and by the time they were 7-years-old, the children were made to undergo IQ tests, according to Newsmax.

The study showed that kids living in the polluted areas, who also belong to the poorest families, have scored lower than 6.6 points in IQ tests compared to other groups, according to a report from the New York Post.

The study further revealed that their "working memory" and "perceptual reasoning" are at 8 points and 5.7 points lower than average. These two factors affected the way they plan, visualize and carry out solutions to non-verbal problems what were presented to them.  

"The findings are a concern because, as has been shown with lead [poisoning], even a modest decrease in IQ can impact lifetime earnings," the study indicated, as published in NY Post.

The research was done in conjunction with a previous study also done at Columbia that links PAHs to developmental delays, anxiety and depression. The latest findings confirm that its impact is long-lasting.