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The Best Science Writing Online 2012
Showcasing more than fifty of the most provocative, original, and significant online essays from 2011, The Best Science Writing Online 2012 will change the way...
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When Deidre Ramos moved with her infant son to the Parker Street section of New Bedford, Mass., little did she know that her new neighborhood was toxic.
Today, a decade later, Ramos is worried about the health of her two sons growing up in a community contaminated by an old burn dump containing polychlorinated biphenyls (PCBs).
“What will be the long-term effects on my children?” asked Ramos.
Now new research conducted in New Bedford suggests that these industrial chemicals, which were first linked to learning problems in children more than two decades ago, may play a role in attention-deficit hyperactivity disorder (ADHD), too.
Boys who were exposed to higher levels of PCBs in the womb scored lower on focus and concentration tests, which indicates that they are more likely to have attention problems often related to ADHD, according to a newly published study of New Bedford area children.
All of the children studied were born to mothers who lived near the contaminated harbor and dumpsites in these low-income communities, where twice as many people live below the poverty line than the Massachusetts average. But experts say that their exposure levels were fairly low, comparable to people's levels throughout much of the United States, which means that a connection between PCBs and attention problems in boys could exist in other communities, too.
Banned in the United States more than 30 years ago, PCBs are long-lived industrial chemicals that accumulate in food chains. Nearly every U.S. resident still has detectable levels in his or her blood. PCBs have the ability to disrupt hormones, which can alter how the brain develops.
“These findings contribute to a growing literature showing associations between PCBs and ADHD-related behavior,” the scientists from Boston University, Harvard University and two other institutions wrote in the study, which was published in late February.
In the study, umbilical cord was collected from 788 newborns from four towns near New Bedford Harbor to see what they were exposed to in the womb. They were born between 1993 and 1998.
Blood from the umbilical cord “is one of the best measures of contaminants being transferred from mother to fetus,” said Sharon Sagiv, lead author of the study and an epidemiologist who now works at Boston University.
Roughly eight years after they were born, almost 600 of these children underwent two tests. One measured their ability to zero in on and react to a specific target – in this case, the image of a cat on a computer screen -- and to inhibit their response to another animal's image. The other exam included parts of an IQ test that measured their processing speed and distractability, which tests whether they can maintain attention over time.
“It’s like playing whack-a-mole versus watching a radar monitor,” said Paul Eubig, a neuroscientist at the University of Illinois at Urbana-Champaign. Eubig, who studies effects in lab animals, was not involved in the study but co-authored a published report linking PCBs with changes related to ADHD.
Boys exposed to the highest levels of PCBs during their mother’s pregnancy failed to press a button for the on-screen cat 12 percent more often than children exposed to the lowest levels, according to the study published in the journal Environmental Health Perspectives. Those same boys also scored slightly lower in the other test.
The same link was not found in girls. Animal data suggest that hormone-disrupting chemicals including PCBs affect each gender differently, but the connection in humans remains unclear.
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8 Comments
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Reply | Report Abuse | Link to this"There is no evidence linking PCBs and autism."
Is there evidence that PCB exposure does not cause autism, or merely the absence of studies evaluating that possibility?
Autism also preferentially affects male children - perhaps PCBs or some other environmental contaminant impedes hormonal development, resulting in autistic symptoms.
Also, I always wonder how children are affected by such inane tests - pushing a button in response to a cat image. As a child or an adult, I would have not been interested in participating.
PCBs are just one member of a rogue's gallery of pollutants that harm our health and reduce our productivity. The article didn't mention this, but I doubt the companies or individuals that released these compounds into the environment are paying for the cleanup, leaving us taxpayers with the bill. The Superfund has been grossly underfunded and many companies involved in the program skip out on their payments. Maybe they're waiting to inflate the problem away or they know their lobbyists and lawyers can shield them from liability at a lower cost than actually protecting people's health.
Reply | Report Abuse | Link to thisWhile the effects of PCBs weren't clear at the time most of the contamination was taking place, the impacts of many other pollutants are abundantly clear. The Tobacco Industry fought intensely to hide the link between their products and health effects like lung cancer and emphasema for decades after they KNEW about these threats. It was more about protecting profits and shielding the company from liability than actually trying to arrive at a scientific truth.
Today, fossil fuel companies are following in the Tobacco Industry's footsteps, sometimes employing THE VERY SAME folks who carried water for the Tobacco Industry at organizations like the Heartland Institute. It's just another ruse to protect profits and shield them from liability. After all, how could they know that CO2 was bad if they manufactured a scientific controversy to cast doubt on sound science for decades? If we let them get away with it, THE WHOLE PLANET will be a giant Superfund site and we'll be paying the cleanup bill for 100 generations.
Again, "sault", you are absolutely correct. In West Virginia, where there are a great abundance of chemicals in the atmosphere, water and land caused by oil companies, gas companies, coal companies, and plastic manufacturing companies, our children is number one in the nation in chronic childhood diseases and number one in the nation in ADD and ADHD like disorders. These companies come out with test results and commercials everyday in denying that they have or had anything to do with the unbelievable amount of medical problems in the children. It is amazing how stupid some people are when they refuse to realize that these problems did not exist until these companies came into the state and started dumping their waste into our water, onto our land and spewing it into our atmosphere. The medical problems these companies create is not worth the pathetic jobs they provide to a semi-mentally retarded population.
Reply | Report Abuse | Link to thisShame it takes science so long to catch up to what we all know in our hearts. This wanton spewing of chemical stew into our air and water will be our doom.
Reply | Report Abuse | Link to thisWe are all guilty; we all buy the stuff that causes the problems. We must change who we are and what we believe to be important in life.
As long as we worship the almighty dollar at the church of Wall Street we deserve what we get.
I must agree with rickbb. A model of "growth" has been predicated for "prosperity." Not only is this a problem in a closed, global world whose limits we are hitting fast, but it has led to greed induced and dangerous artifices. Mass media/psychology used to produce artificial needs, needless replication of similar products, and artificial obsolescence of the same. Vast army's of media, packaging, lawyers, shippers, distributors, and natural resource plunderers -- and of course, really armies from private security to police and military of the state. This, even before we get into the Murphy's law after-effects of the production, distribution, and use of these products.
Reply | Report Abuse | Link to thisIf we took mutual responsibility, saw to real vital needs of people rather than get-rich hype, we could feed and clothe, and house the 7 billion of this planet -- not by starvation standards, but comfortably.
We will depart to this, rapidly by intelligent grassroots education and non-coercive consensus. Or alternatively, by pain as products are not bought because the customer base, exhausted, impoverished, and sick -- drys up.
It is always better to plan a surgery than to be rushed to emergency. Let us hope that we go the path of best odds, and that the patient yet survives and comes to new health and vigor.
engineer.sci has spoken well about our motivation towards profit replacing all common sense. Isn't it painful enough that our most precious resource, our children are being affected at an important level of functioning? As a mother, I find it intolerable to acquiesce to my children and grandchildren and neighbors being poisoned for profits. Do we really believe we are somehow immortal and that we can actually "advance" and "progress" while slowly killing ourselves, our capacities and our environment? Perhaps our business and regulatory leadership has sustained the most profound brain damage of all and become delusional? Seriously, there is a delusion and that is that we can continue like this indefinitely.
Reply | Report Abuse | Link to thisGood points Sault and others. Our lack of foresight and control on many substances is, sadly, going to cost us in many intangible ways because of mild health and developmental issues that take a huge toll on people's lives over many years.
Reply | Report Abuse | Link to thisLook, you're not fooling anybody. Either come clean and join the discussion under another name if you want to post here or GTFO. What are you trying to prove? You want to make me look bad? Derail the discussions we have around here? Seriously, all the REAL people I disagree with and debate on these boards know what's going on here. All the people that come here looking to see what others are saying about these articles are just confused. YOU ARE WASTING EVERYBODY'S TIME.
Reply | Report Abuse | Link to thisBut hey, the more you mess with me and try to sully my reputation, the more I know I must be doing SOMETHING right!