A 'Silent Pandemic' Of Brain Disorders

Researchers Say Chemical Exposures May Explain Rise in Autism And ADHD

(WebMD)  Exposure to industrial chemicals may be responsible for a "silent pandemic" of brain development disorders affecting millions of children worldwide, and not enough is being done to identify the risks.

That is the contention of two researchers who have studied the effects of chemical exposures on brain development for many decades.

In an essay published online in the journal The Lancet, the researchers identified 202 potentially harmful industrial chemicals that may be contributing to dramatic increases in autism, attention deficit hyperactivity disorder (ADHD), and other brain disorders among children.

Roughly half of the chemicals are in common use, but very few have been tested to determine their impact on brain development.

"The bottom line is you only get one chance to develop a brain," Philippe Grandjean, M.D., of the Harvard School of Public Health, tells WebMD. "We have to protect children against chemical pollution because damage to a developing brain is irreversible."

Tip of the Iceberg

Grandjean and co-author Philip Landrigan, M.D., of New York's Mount Sinai School of Medicine, noted that of the industrial chemicals known to be toxic to the human brain, only five — lead, mercury, arsenic, PCBs, and toluene — have been proven to cause damage to the developing brain.

These chemicals have been identified not because they are necessarily more dangerous than the others, but because they have been studied the most, Grandjean and Landrigan contend.

"The few substances proven to be toxic to human neurodevelopment should be viewed as the tip of a very large iceberg," they wrote.

Grandjean spent decades documenting the toxic effects of mercury exposure on the developing brain, and Landrigan spent decades studying the effects of lead exposure in children.

Lead and mercury are among the few chemicals that are now strictly regulated to protect children. But regulation came long after the dangers were first recognized.

Lead-based paint was first linked to sickness in children more than a century ago, but lead was not removed from paint and gasoline in the U.S. until the late 1970s and early 1980s.

"Despite those early pediatric warnings, the largely unchecked use of lead in petrol, paints, ceramic glazes, and many other products through much of the twentieth century caused continued risk of lead poisoning," the researchers write.

A Generation Exposed

Almost all children born in industrialized countries between 1960 and 1980 were exposed to substantial amounts of lead from gasoline. The researchers write that lead exposure in this population could be responsible for a substantial reduction in average IQ scores.

"A generation of American children was exposed to this very dangerous neurotoxin while we were doing traditional risk assessment," Grandjean tells WebMD. "We can't afford to make the same mistake again."

Annette Kirshner, Ph.D., of the National Institute of Environmental Health Sciences (NIEHS) agrees that more expeditious ways of identifying chemical exposures that put children at risk are needed.

The prevailing thinking among researchers studying autism and ADHD is that both genetic and environmental factors play a role in the childhood brain disorders.

"There is still no good evidence linking any single environmental exposure to autism and ADHD," Kirshner tells WebMD. "It will probably require a global effort to understand the combination of factors that lead to these disorders."

But Grandjean and Landrigan argue that exposure to industrial chemicals appear to have created a "silent pandemic in modern society."

"Although these chemicals might have caused impaired brain development in millions of children worldwide, the profound effects of such a pandemic are not apparent from available health statistics," they wrote.

SOURCES: Grandjean, P. and Landrigan, P.J. The Lancet, Nov. 8, 2006; Vol. 368: online edition. Philippe Grandjean, M.D., department of environmental health, Harvard School of Public Health, Boston; Annette Kirshner, Ph.D., health science administrator, National Institute of Environmental Health Sciences.

[sy2502]

talkingham, you obviously didn't read my post in its entirety. I have already agreed that there are kids with real disorders that need treated. I just don't think that every case labeled as ADD is actually a mentaly hill kid. I think we have pre-canned ideas of how they should behave and consider every deviation from it a hillness, instead of accepting their differences. I think that instead of dealing with bad behavior or difficult behavior with patience and firmness, we deal with it with pills.
I saw a program about a school for so called ADHD kids where they had a trampolin in the corner of the room, and whenever a kid started acting out because he couldn't sit still and quiet too long, they would send him to jump on the trampolin for a bit, expend some energy, then come back. Worked great, no drugs required.

[pf16alex]

Increased age at childbearing (paternal) is also a risk factor for faulty brain development in children. This trend plus the chemical exposure is adding to epidemic of brain disorders.

[talkingham]

So your contention is that all the research is wrong or contrived and that an ever increasing number of children are just poorly behaved. Well many of these kids, especially those diagnosed with autism show classic markers of brain disorders (quite different from mental illness by the way) coupled with little or no speech devlopment, and/or profoundly repetitive behaviors far beyond traditional anti-social misbehavior. Whether it's the toxins that have been poured into the ground and into our ecosystems or the absurd range of unnatural chemical substances added to just about every commercial food product one buys these days for children -- your contention is that these additives have no negative effect and should not be investigated. There's a fast food food hamburger waiting on you and your child that has the parts of about 1,000 cattle in it waiting for you at Burger King. Go for it.

[sy2502]

I am very skeptical of this "pandemic" of brain disorders decried here in the US. The problem is that we expect the children to be miniature adults, to sit down and stay still for hours when they are 3 years old, not to fight with each other, to be quiet, to do homework and study at an age when they should be running around, play, scream and laugh. When they can't do that, we slap a nice ADD label on them, and medicate them. The problem isn't with the children, who are behaving as they should, but with these overworked, self-indulging parents who want their kids to be quiet, when they come home tired from work, and child care professionals who just want their job to be easy without having to make the effort to accomodate all kinds of children. I don't deny that there are kids with real mental problems, who should be taken care of, but I have seen way too many perfectly normal kids whose only sin was to be active, happy, outgoing, noisy, being medicated to fit some kind of social mold that just isn't for them. Let kids be kids, accept their diversity of character, skills and personality.

[navotny]

and a follow up to that....there are a very FEW people in the general population that have allergic reactions to ASPARTAME...just like any other substance that we eat or expose ourselves too. This makes sense. BUT there are no documented cases of permenant brain damage or any other significant illness (other than the allergic reactions) attributed to this chemical. Yes, you can find tons of speculation and psuedo science garbage about this substance on the web. But if any of that garbage were factual, and it is NOT, the substance would have warnings on it. (all products containing aspartame sold in the US do...its an allergy alert).
SUGAR...which is natural, causes death and disease in the millions every year...diabetes, heart disease etc. your learned and eminent and responsible folks need to research your facts a little better...and don't use the crackpot science that so many use to back up your claims.

[navotny]

Aspartame? LOL! Wow people who continue to dwell on a substance made from bananas and milk just baffle my mind. This is coming from a country that had what, 30 people die of contaminated beef from a horrible disease because of the way they raise cattle (MAD COW DISEASE). No one has ever died of aspartame..no one.
Our FDA, just like any other agency, is not 100% perfect. Historically though, US food supply has been the safest in the history of this planet. While companies like BP (British Petroleum) continue to pollute the world with petro-chemical contamination, as the article is talking about when it speaks of the neurotoxin LEAD in gasoline.
The psuedo science that fuels the fears of the ignorant about substance like aspartame and other food additives causes the unnecessary attention and waste of energy on fighting causes of no real worth. These people should be investigating the petro-chemical industry...you will find much to complain about there.

[daviduk-2009]

I have only one word to convey to the American readers of the above article in relation to brain damage and poor development. That word is
ASPARTAME. The eminent and learned folks responsible for this report have missed a very important factor by excluding meaningful and honest research into this product. We have a saying in England appertaining to dubious substances, "If In Doubt, Kick It Out" and there are certainly a major doubts over this product.
How many more suffering children will it take before your FDA places a total ban on this evil sweet poison. Maybe you are afraid of the litigation which will result.
David Roberts UK

[tinwoman69k]

hmmm that's why there's an alternative to silver fillings that's not a metal.....

[tbooton-2009]

But it still is okay to inject thimerosal(a mercury based preservatine) into newborns and pregnant women. Oh, and it's still okay to get silver fillings (mercury). Totally safe!!

[Syndicate]

Big deal. The greater cause of brain disorders are Viruses. Which are curently uncontrollable. Memory loss with age may be caused by an inflamation of the brain. Die hard Bush supporters are explained simply, Gore, Kerry, Dean and a million other liberals calling Bush Hitler or calling those of us who voted for him stupid. I seriously doubt any of Bushes critics could do better. You could do a lot worse.

[shingles1]

"Exposure to industrial chemicals may be responsible for a "silent pandemic" of brain development disorders affecting millions of children worldwide..."

Oh, so THAT explains diehard Bush supporters.

[jetlizhan]

Jarehan - what the hell are you trying to say? You really scare me with your off the walls jargon.

Now to get back to the real subject at hand - my 7 yr old grandson has the 'silent epilepsy' and is on medication for it; he also has ADHD. If he weren't in the care of skilled physicians and medication, he would literally drive himself crazy, as he has told me this. He absolutely cannot help his 'ping pong activeness'. We are all hoping and praying he'll outgrow the epilepsy, and maybe even the ADHD. He's an outstanding athlete in baseball and soccer, is an honor student and his teachers absolutely love him in class. He's popular, cute as a button, has wonderful loving and caring parents, whom love this child with all their hearts. No social dysfunctions whatsoever. I guess my point is, any of the brain disorders can hit any family at any given time.

[jarehan-2009]

I can't understand why people will keep pointing to "environmental factors," but they won't look at the social factors that may also be contributing to the increase.

For example, the abundance of wealth, to those with skills in technology, post-World War II and during the Cold War era...

A higher income determines a larger change of success --

In other words, people who may have had more difficulty breeding, suddenly had an easier time at it.

If there are social factors (environmental pressures) leading to different personality types...

If only makes sense, that the ratio of those personality types will fluctuate as technology and civilization progresses.
Therefore... While factors like mercury may contribute...

In the larger picture, they are almost irrelevent.

Today's "normal person" is tomorrow's "crazy person" -- and vice versa.

If you win the war, you get to write the history books.

It's practically the same with psychiatry.

- Jarehan