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

Jul 20, 2009

A mother's exposure to urban air pollutants known as polycyclic aromatic hydrocarbons (PAHs) can adversely affect a child's intelligence quotient or IQ, a study reports. 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, 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 than those of less exposed children. High PAH levels were defined as above the median of 2.26 nanograms per cubic meter (ng/m3). A difference of four points, which was the average seen in this study, could be educationally meaningful in terms of school success, as reflected, for example, in standardized testing and other measures of academic performance. However, the researchers point out that the effects may vary among individual children.

"This research clearly shows that environmental PAHs at levels encountered in an urban setting can adversely affect a child's IQ," said Linda Birnbaum, Ph.D., director of NIEHS. "This is the first study to report an association between PAH exposure and IQ, and it should serve as a warning bell to us all. We need to do more to prevent environmental exposures from harming our children."

The study was conducted by scientists from the Columbia University Center for Children's Environmental Health. It included children who were born to non-smoking black and Dominican-American women age 18 to 35 who resided in Washington Heights, Harlem or the South Bronx in New York. The children were followed from utero to 5 years of age. The mothers wore personal air monitors during pregnancy to measure exposure to PAHs and they responded to questionnaires.

At 5 years of age, 249 children were given an intelligence test known as the Wechsler Preschool and Primary Scale of the Intelligence, which provides verbal, performance and full-scale IQ scores. The test is regarded as a well validated, reliable and sensitive instrument for assessing intelligence. The researchers developed models to calculate the associations between prenatal PAH exposure and IQ. They accounted for other factors such as second-hand smoke exposure, lead, mother's education and the quality of the home caretaking environment. Study participants exposed to air pollution levels below the average were designated as having low exposure, while those exposed to pollution levels above the median were identified as high exposure.

"The decrease in full-scale IQ score among the more exposed children is similar to that seen with low-level lead exposure," said lead author Frederica P. Perera, Dr.P.H., professor at Columbia's Mailman School of Public Health and director of the Columbia Center for Children's Environmental Health.

"This finding is of concern," said Perera. "IQ is an important predictor of future academic performance, and PAHs are widespread in urban environments and throughout the world. Fortunately, airborne PAH concentrations can be reduced through currently available controls, alternative energy sources and policy interventions."

More information: Perrera, FP, Zhigang L, Whyatt R, Hoepner L, Wang, S, Camann D, Rauh V. 2009. Prenatal Airborne Polycyclic Aromatic Hydrocarbon Exposure and Child IQ at Age 5 Years. Pediatrics. 124(2). August, 2009.

Source: NIH/National Institute of Environmental Health Sciences

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finitesolutions
1.7 / 5 (6) Jul 20, 2009
I have done a study on my own also: the american citizenship also makes you stupid. Americans provoke wars in which they kill smart people.
Doug_Huffman
5 / 5 (4) Jul 20, 2009
This "study" dismissed each confounding variable to reach their desired conclusion.

Herrnstein & Murray reached similar conclusions without 'pollution.'

If a 5 point reduction in IQ is bad then why is not the exceptionally good encouraged.

The conspiracy of ignorance masquerades as common sense.
JerryPark
5 / 5 (3) Jul 20, 2009
Lets see:
1) The study used an extremely small sample -- 249.
2) The sample was taken from a single geographical area.
3) The "exposure" monitoring consisted of one 48 hour period.
4) All other possible correlations were discounted.

Conclusion: Useless and biased conclusions based on statistically insignificant differences.
Velanarris
5 / 5 (3) Jul 20, 2009
They also played the fun game of not establishing a specified baseline.

It's well known that race, poverty level, food, and multiple other factors influence the IQ of the unborn.

If these 200 someodd women were all eating doritos and drinking mountain dew for their pregnancy I'd be surprised there wasn't a larger drop in IQ.

Now we all know that standard urban smog most likely does have some detriment to the unborn, and I wouldn't doubt that there is an effect on IQ, but there's too much noise in this study to make any sort of definitive conclusion.

I have done a study on my own also: the american citizenship also makes you stupid. Americans provoke wars in which they kill smart people.
Because blowing yourself up in hopes of spending eternity with 72 virgins over a dispute about "my god is bigger than your god" that started more than 2000 years ago is the pinnacle of intellect. Because cutting electricity off from the citizenry you're there to protect and help prosper while they live a hunter gatherer existence is the pinnacle of intellect. Because threatening all of Europe with a faulty eugenics program full of racism and a "mother/father race" while killing thousands of people with another ethnicity is the pinnacle of intellect.

Dig that hole deeper.
PaulLove
5 / 5 (2) Jul 20, 2009
I have done a study on my own also: the american citizenship also makes you stupid. Americans provoke wars in which they kill smart people.


I see a message in the sky it says "GOATS" apparently the pinnacle of technology of the brilliant. They don't make their cars, they don't make the guns they use to conduct terrorist activities, they know little of medicine and don't even grow enough to feed themselves. I cower before the towering "innilekt" of these "smert" people.

Move to alternative energy then when the machinery they didn't make breaks because they can't fix it they may live the simple pure life of goatherds as they slowly starve in their caves and their children die of simple maladies that could have been cured.
QubitTamer
3.4 / 5 (5) Jul 20, 2009
I have done a study on my own also: the american citizenship also makes you stupid. Americans provoke wars in which they kill smart people.


Wow, how about let's rephrase that to - "I have done a study on my own also: People who have zero intellectual capacity or curiosity to read an 8th grade history book to learn the FACTS about all the people the USA has saved in the last hundred years (World War I, World War II, The Korean War, Greneda, Panama, The Liberation of Kuwait (Gulf War I) instead slurp up all of the leftist bullshit from pop culture and regurgitate it in hopes of appearing cool and popular anywhere and everywhere they can. Remember it was just as cool in Nazi germany to be seen insulting and laughing at Jews as it is today to laugh and insult Christians and conservatives.

Let me tell all you Twittering / Facebooking narcisists something... Your time of shitting on liberty and ridiculing the people and principles that built America is coming to an end. Go ahead and 1 vote this post. You have the liberty to do that, reject message and pass judgement on it because of the thousands of brave men and women who went out and died for your security and your freedom so you would have plentiful and cheap food, plentiful and cheap water, plentiful and cheap electricity, and not live in some hellish 3rd world nightmare land like North Korea or Iran or the Sudan... Go ahead and 1 vote this post. Let it serve as a judgement on you one day when you stand before the one who knows all your truths and all your lies.

QubitTamer
not rated yet Jul 20, 2009
Back on topic. Physorg needs a real shakeup in their editorial staff if they are going to simply copy and paste drivel like this sad abomination of a study... I guess the environmental wackjobs are running the show there now, so anything which paints a picture of environmental doom is fit to post!
Doug_Huffman
not rated yet Jul 20, 2009
Go read the Scientific American epitaph at John Baez' site. PhysOrg.asm is going the same way, victim of sales weasels' marketeering.
Avitar
not rated yet Jul 20, 2009
This rehashes old ground with new instruments.
defunctdiety
not rated yet Jul 20, 2009
I have done a study on my own also: the american citizenship also makes you stupid. Americans provoke wars in which they kill smart people.


I really don't even understand what he's saying, or what point he's trying to make... can someone (the OP preferably) please explain this to me?
MatthiasF
not rated yet Jul 20, 2009
Seems like the anti-petroleum movement is trying their best to make up more reasons to outlaw combustion automobiles.

I don't understand why a study with such a small sample, targeting such specifically low-income areas and making such egregious statements can be allowed from a prominent university.
finitesolutions
not rated yet Jul 20, 2009
Here I go: war == death. There has not been any war with no victims. So when you start a war ( formaly or informaly ) you do intend to kill people. Better not even start the war: suck it up and move on. Just winning a war is not enough. We should know this by now. There have always been reasons for wars... and probably will always be.
defunctdiety
3 / 5 (2) Jul 21, 2009
I still don't think I get the thrust of your OP... you seem to be kind of all over.

the american citizenship ... provoke wars


Wrong. The citizens of America have never provoked a war with a foreign entity. Our government may have done and may do so in our name, but very very few wars have been "popular" in America. Most Americans wish our government would focus on our own considerable problems. And the wars that were "popular", were not without very valuable principle.

There has not been any war with no victims. So when you start a war ( formaly or informaly ) you do intend to kill people.


And some people intend to kill other people because of the way they live. That's a greater tragedy, IMHO. Hatemongers, not unlike you with your anti-US citizen rhetoric, are most usually the cause of wars.

Better not even start the war: suck it up and move on. ... There have always been reasons for wars... and probably will always be.


You may not feel this way, but I believe some things are worth dieing for. And lucky for you and every other pacifist, many people believe there are principles worth dieing for.

war == death


Here's a biology and history and future lesson for you, finitesolutions. Life = death. But really, I would say life < death. Anyone can find something to live for, that's easy, but find something to die for, and that's something special. Do have anything you'd die for, that you'd kill for?
Velanarris
1 / 5 (2) Jul 21, 2009
Here I go: war == death. There has not been any war with no victims. So when you start a war ( formaly or informaly ) you do intend to kill people.
Have you heard of a war of ideology? Or perhaps a revolution in thought? Maybe cultural war? All of the above are wars that don't require deaths, that is unless you're counting the death of ideas.

Better not even start the war: suck it up and move on. Just winning a war is not enough. We should know this by now. There have always been reasons for wars... and probably will always be.


So would you enjoy living out your days in a concentration camp in Germany in the 40's? Maybe in Cambodia in the 60's? How about in Croatia in the 80's? Maybe French Guyana in the 90's? How about in Rwanda now?

Sometimes the lives of a few must be sacrificed for the survival of the many. The primary occupation of wartime generals is to ensure that the lives of the few is the smallest "few" possible, while maintaining the health and well being of the largest "many" possible.
Otto1882
1 / 5 (1) Jul 25, 2009
Those of you arguing that America is the great liberator of mankind really need to realize that these opinions are based on propaganda and don't necessarily have much basis in reality.

Every nation on Earth for all of history have used and continue to use propaganda. A nation's propaganda has the sole purpose of influencing the popular opinion. Truth more often than not has nothing to do with it, especially in times of war.

Sadly, nobody seems to learn the often uttered quote "In war, truth is the first casualty" by Aeschylus when examining the nature of a nation's role in a war and more importantly critically examining the war-time claims against adversary nations.

The Iraq WMD propaganda is a recent example and the claims by the British in WWI that the Germans were crucifying Allied soldiers is another older one.

You American apologists are not much different in many respects than the clown calling those holding American citizenship idiots.
Shootist
not rated yet Jul 25, 2009
This "study" dismissed each confounding variable to reach their desired conclusion.

Herrnstein & Murray reached similar conclusions without 'pollution.'

If a 5 point reduction in IQ is bad then why is not the exceptionally good encouraged.

The conspiracy of ignorance masquerades as common sense.


But it does explain Los Angeles
Shootist
not rated yet Jul 25, 2009
Here I go: war == death. There has not been any war with no victims. So when you start a war ( formaly or informaly ) you do intend to kill people. Better not even start the war: suck it up and move on. Just winning a war is not enough. We should know this by now. There have always been reasons for wars... and probably will always be.


Well Europe could have been left to the little Austrian paper hanger and his good buddy, Iosif Vissarionovich Stalin.
John_balls
1 / 5 (1) Jul 27, 2009
I have done a study on my own also: the american citizenship also makes you stupid. Americans provoke wars in which they kill smart people.






Wow, how about let's rephrase that to - "I have done a study on my own also: People who have zero intellectual capacity or curiosity to read an 8th grade history book to learn the FACTS about all the people the USA has saved in the last hundred years (World War I, World War II, The Korean War, Greneda, Panama, The Liberation of Kuwait (Gulf War I) instead slurp up all of the leftist bullshit from pop culture and regurgitate it in hopes of appearing cool and popular anywhere and everywhere they can. Remember it was just as cool in Nazi germany to be seen insulting and laughing at Jews as it is today to laugh and insult Christians and conservatives.















Let me tell all you Twittering / Facebooking narcisists something... Your time of shitting on liberty and ridiculing the people and principles that built America is coming to an end. Go ahead and 1 vote this post. You have the liberty to do that, reject message and pass judgement on it because of the thousands of brave men and women who went out and died for your security and your freedom so you would have plentiful and cheap food, plentiful and cheap water, plentiful and cheap electricity, and not live in some hellish 3rd world nightmare land like North Korea or Iran or the Sudan... Go ahead and 1 vote this post. Let it serve as a judgement on you one day when you stand before the one who knows all your truths and all your lies.


















You fking idiot. When will you and your ilk realize that it's never about freedom it most about business and power and nothing else.

The people that usually say this just don't have a good grasp of history which will tell you why we fight and for what reasons. It's usually not about freedom. We have put more dictators in power then you can probably count.
Velanarris
5 / 5 (1) Jul 27, 2009
You fking idiot. When will you and your ilk realize that it's never about freedom it most about business and power and nothing else.

The people that usually say this just don't have a good grasp of history which will tell you why we fight and for what reasons. It's usually not about freedom. We have put more dictators in power then you can probably count.
We fight because we're afraid we'll run out of something. If the resource is infinite, we won't fight over it.

And as for the US standing up dictatorships you're right, because we care about other people about as much as they care about us. If standing up a dictator means the government will give us what we want, then that is exactly what we do. It's called imperialism, Europe was really good at it back in the day.