Air pollution from cars and cigarettes can lower a child's IQ. That's the finding of a new study that tracked mothers and their children living in Washington Heights, Harlem, and the South Bronx.

Researchers outfitted pregnant mothers with devices that monitored air for levels of PAHs, chemicals that are produced when oil, gasoline, coal, tobacco, and other organic substances are burned. The data from these monitors was then compared to the results of intelligence tests given to those mothers' children when they reached 5 years old. Among those children who had high exposure to PAHs, IQ scores were 4 to 5 points lower than their less-exposed peers—that's on par with the effects of lead in low doses.

Lead study author Dr. Frederica Perera says: "This finding is of concern because IQ is an important predictor of future academic performance, and PAHs are widespread in urban environments and throughout the world." And as Johns Hopkins environmental health specialist Patrick Breysse tells the Daily News, those PAH effects may help explain why inner city kids don't perform as well academically as wealthier kids.

But PAHs aren't just found in inner city neighborhoods. Besides coming from tailpipes and, well, actual pipes, PAHs are also released by burning incense, cozy glowing fireplaces, and tasty barbecue. The grill marks on meat are, in fact, filled with the stuff, so maybe hold off on the blackened chicken for little Suzy until after she takes her SATs.