Children's IQ can be affected by mother's exposure to urban air pollutants

July 20, 2009 -- Prenatal exposure to environmental pollutants known as polycyclic aromatic hydrocarbons (PAHs) can adversely affect a child's intelligence quotient or IQ, according to new research by the the Columbia Center for Children's Environmental Health (CCCEH) at the Mailman School of Public Health. PAHs are chemicals released into the air from the burning of coal, diesel, oil and gas, or other organic substances such as tobacco. In urban areas motor vehicles are a major source of PAHs. The study findings are published in the August 2009 issue of Pediatrics.

The study, funded by the National Institute of Environmental Health Sciences (NIEHS), a component of the National Institutes of Health, the U.S. Environmental Protection Agency and several private foundations, found that children exposed to high levels of PAHs in New York City had full scale and verbal IQ scores that were 4.31 and 4.67 points lower, respectively than those of less exposed children. High PAH levels were defined as above the median of 2.26 nanograms per cubic meter (ng/m3).