Text Version
RSS Feeds
Newsletter
Home Forum Photos Features Newsletter Archive Employment
About US Help Site Map
SEARCH   About US FAQ Site Map Site News
  SERVICES
  -Text Version
  -RSS Feeds
  -Newsletter
  -News Archive
  -Give us feedback
  -Voices of Readers
  -Online community
  -China Biz info
  What's new
 -
 -
Smog drains brain
+ -
16:42, July 22, 2009

Click the "PLAY" button and listen. Do you like the online audio service here?
Good, I like it
Just so so
I don't like it
No interest
 Comment  Tell A Friend
 Print Format  Save Article
Researchers for the first time have linked air pollution exposure before birth with lower IQ scores in childhood, bolstering evidence that smog may 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 exhausts.

The children were given IQ tests at age 5, before they started school. Those exposed to the most pollution before birth scored on average four to five points lower than children with less exposure.

And that's a difference that could affect children's performance in school, says 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, says 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 belching factory to face pollution health risks, and that there may be more dangers from typical urban air pollution than previously thought, he says.

"We are learning more and more about low-dose exposure and how things we take for granted may not be a free ride," he says.

While future research is needed to confirm the new results, the findings suggest that exposure to air pollution before birth could have the same harmful effects on the developing brain as exposure to lead, says Patrick Breysse, an environmental health specialist at Johns Hopkins' school of public health.

And along with other environmental harms and disadvantages low-income children are exposed to, it could help explain why they often do worse academically than children from wealthier families, Breysse says.

"It's a profound observation," he says. "This paper is going to open a lot of eyes."

The study in next month's edition of Pediatrics was released on Monday.

In earlier research, involving some of the same children and others, Perera linked prenatal exposure to air pollution with genetic abnormalities at birth that could increase risks for cancer; smaller newborn head size and reduced birth weight. Her research team also linked it with developmental delays at age 3 and with children's asthma.

The researchers studied pollutants that can cross the placenta and are known scientifically as polycyclic aromatic hydrocarbons. Main sources include vehicle exhaust and factory emissions. Tobacco smoke is another source, but mothers in the study were non-smokers.

A total of 140 study children, 56 percent, were in the high exposure group. That means their mothers likely lived close to heavily congested streets, bus depots and other typical sources of city air pollution; the researchers are still examining data to confirm that, Perera says. The mothers were black or Dominican-American; the results likely apply to other groups, researchers say.

The researchers took into account other factors that could influence IQ, including secondhand smoke exposure, the home learning environment and air pollution exposure after birth, and still found a strong influence from prenatal exposure, Perera says.

Dr Robert Geller, an Emory University pediatrician and toxicologist, says the study can't completely rule out that pollution exposure during early childhood might have contributed.

He also notes fewer mothers in the high exposure group had graduated from high school. While that might also have contributed to the high-dose children's lower IQ scores, the study still provides compelling evidence implicating prenatal pollution exposure that should prompt additional studies, Geller says.

The researchers say they plan to continuing monitoring and testing the children to learn whether school performance is affected and if there are any additional long-term effects.

Source: China Daily





  Your Message:   Most Commented:
Unveiled Rebiya Kadeer: a Uighur Dalai Lama
80 pct of netizens agree China should punish Facebook
Chinese netizens call for punishing Turkey
LA police: Michael Jackson death may have been 'homicide'
Public angered by Turkish PM's 'genocide' accusation

|About Peopledaily.com.cn | Advertise on site | Contact us | Site map | Job offer|
Copyright by People's Daily Online, All Rights Reserved

http://english.people.com.cn/90001/6707335.pdf