Pollution from cars makes our kids dumber

In-womb exposure to components of air pollution can depress childrens' IQ scores about as much as exposure to lead, new research shows.

In fact, it might cause as much of a diminution of intelligence as fetal alcohol syndrome, according to a Science News story by Janet Raloff.  The research by Columbia University's Frederica Perera traced exposure of expectant mothers in New York City's Harlem, South Bronx and Washington Heights neighborhoods to components of auto exhaust known as polycyclic aromatic hydrocarbons

. (I can say that five times fast -- can you?)

The exposed children showed an average IQ drop of 4.3 points. While that doesn't sound like much unless it's your own child, Bruce Lanphear of Simon Fraser University, just up the road in Vancouver, B.C., told Raloff that if one extrapolates that across the whole United States:

A downward shift in IQ by 5 points will increase by 3.5 million the number of children who meet the criteria for mental retardation.

It's a pretty clear case of a situation where controlling the pollution would be cheaper for society in the long run, Raloff writes.

Perera's paper was one of several discussed this week at a National Academies of Science workshop that also touched on how car-based pollutants can spark athsma, and how contaminants can turn genes on and off even if they don't outright damage DNA.

The workshop, covered in a wide-ranging story by Bette Hileman in Environmental Health News, delved into whether pollutants might be doing damage by turning off genes, or turning them on at the wrong time in an organism's development. This field of epigenetics spurs some interesting theories, suggesting that in some instances damage done to genes is more important than the environment in which the organism -- in this case, us -- lives in after birth. One researcher told Hileman:

Asking heart attack victims what they ate this year or last may be far less important than what they were exposed to in the womb and shortly after birth.

Now, if you've read this far in the post you're also going to want to know about a new web tool that will help study how environmental factors relate to disease.  Susan J. Landers of American Medical News covered the story.