CHICAGO — Researchers for the first time have linked air pollution exposure before birth with lower IQ scores in childhood, bolstering evidence that smog might harm the developing brain.
The results are in a study of 249 children of New York City women who wore backpack air monitors for 48 hours during the last few months of pregnancy. They lived in mostly low-income neighborhoods in northern Manhattan and the South Bronx. They had varying levels of exposure to typical kinds of urban air pollution, mostly from car, bus and truck exhaust.
At age 5, before starting school, the children were given IQ tests. Those exposed to the most pollution before birth scored on average four to five points lower than children with less exposure.
That's a big enough difference that it could affect children's performance in school, said Frederica Perera, the study's lead author and director of the Columbia Center for Children's Environmental Health.
Dr. Michael Msall, a University of Chicago pediatrician not involved in the research, said the study doesn't mean that children living in congested cities "aren't going to learn to read and write and spell."
But it does suggest that you don't have to live right next door to a smoke-belching factory to face pollution health risks, and that there might be more dangers from typical urban air pollution than previously thought, he said.
"We are learning more and more about low-dose exposure and how things we take for granted may not be a free ride," he said.