Air pollution is already known to cause respiratory and lung problems in dense urban areas, like New York, and a new study by the Columbia Center for Children's Environmental Health found it can also be linked to ADHD in children.

The Columbia Center studied 233 pregnant New York women and their children from pregnancy to late childhood and found that their kids were five times more likely to develop ADHD-like symptoms. The cause may be exposure to polycyclic aromatic hydrocarbons (PAH), not all that distracting magic the city has to offer. PAHs are air pollutants generated by traffic, residential boilers, and electrical plants burning fossil fuel.

The pollutants can affect the babies even at a prenatal phase, concluded the lead author of the study, Frederica Perera.

"This study suggests that exposure to PAH encountered in New York City air may play a role in childhood ADHD," she said. "Symptoms show up as early as age 3, with developmental delays, to reduced IQ at age 5, and symptoms of anxiety/depression and attention problems at ages 6 and 7."

Struggling with depression and anxiety at the ripe age of 6 leads to problems in school, socializing and home behavior. About ten percent of children in the US have been diagnosed with ADHD, and the percentage of those kids that are medicated increases each year. The causes for ADHD are thought to be partly genetic, but an environmental cause has always been suspected, the Center for Diseases Control said.

Globally and nationally, New York isn't the worst place for air pollution. The American Lung Association gives New York an "F" for Ozone (okay, that's pretty bad), but a "B" for Particle Pollution. The World Health Organization said in May that cities in India and Asia are at the most risk. Seven million people died globally in 2012 from air pollution, and the W.H.O. called it the "world's biggest environmental health risk."

Since health issues have yet to deter humans from polluting the planet, the study makes a final argument in a language everyone can speak: money. The Columbia Center estimates that ADHD costs between $36 and $52 billion in the U.S., with an individual American cost estimated to range from $12,005 to $17,458.