Current Opinion in Pediatrics: What causes autism?

[Guest guest]

The interesting thing about this is one study just showed that women

who have infertility issues have a higher concentration of flame

retardant chemicals in their blood then the general population and two

if a chemical is used in Europe then it has passed a stringent testing

protocol called REACH. SO testing these chemicals is possible as REACH

has shown and these chemicals can cause unintended issues. Therefore

instituting REACH in the US should be easy plus good for the economy

as it will lower health costs.

Also something to remember I have known lobbyists for the plastic

industry and the minute studies showed the plastic mix might be

causing a problem then the industry in the US would quickly but

quietly fix the problem. No body wants to harm others .

http://journals.lww.com/co-pediatrics/Abstract/publishahead/What_causes_autism__\

Exploring_the_environmental.99878.aspx

Current Opinion in Pediatrics:

What causes autism? Exploring the environmental contribution

Abstract

Purpose of review: Autism is a biologically based disorder of brain

development. Genetic factors - mutations, deletions, and copy number

variants - are clearly implicated in causation of autism. However,

they account for only a small fraction of cases, and do not easily

explain key clinical and epidemiological features. This suggests that

early environmental exposures also contribute. This review explores

this hypothesis.

Recent findings: Indirect evidence for an environmental contribution

to autism comes from studies demonstrating the sensitivity of the

developing brain to external exposures such as lead, ethyl alcohol and

methyl mercury. But the most powerful proof-of-concept evidence

derives from studies specifically linking autism to exposures in early

pregnancy - thalidomide, misoprostol, and valproic acid; maternal

rubella infection; and the organophosphate insecticide, chlorpyrifos.

There is no credible evidence that vaccines cause autism.

Summary: Expanded research is needed into environmental causation of

autism. Children today are surrounded by thousands of synthetic

chemicals. Two hundred of them are neurotoxic in adult humans, and

1000 more in laboratory models. Yet fewer than 20% of high-volume

chemicals have been tested for neurodevelopmental toxicity. I propose

a targeted discovery strategy focused on suspect chemicals, which

combines expanded toxicological screening, neurobiological research

and prospective epidemiological studies.

© 2010 Lippincott & Wilkins, Inc.

http://www.nytimes.com/2010/02/25/opinion/25kristof.html

OP-ED COLUMNIST

Do Toxins Cause Autism?

By NICHOLAS D. KRISTOF

Autism was first identified in 1943 in an obscure medical journal.

Since then it has become a frighteningly common affliction, with the

Centers for Disease Control reporting recently that autism disorders

now affect almost 1 percent of children.

Over recent decades, other development disorders also appear to have

proliferated, along with certain cancers in children and adults. Why?

No one knows for certain. And despite their financial and human cost,

they presumably won’t be discussed much at Thursday’s White House

summit on health care.

Yet they constitute a huge national health burden, and suspicions are

growing that one culprit may be chemicals in the environment. An

article in a forthcoming issue of a peer-reviewed medical journal,

Current Opinion in Pediatrics, just posted online, makes this

explicit.

The article cites “historically important, proof-of-concept studies

that specifically link autism to environmental exposures experienced

prenatally.” It adds that the “likelihood is high” that many chemicals

“have potential to cause injury to the developing brain and to produce

neurodevelopmental disorders.”

The author is not a granola-munching crank but Dr. Philip J.

Landrigan, professor of pediatrics at the Mount Sinai School of

Medicine in New York and chairman of the school’s department of

preventive medicine. While his article is full of cautionary language,

Dr. Landrigan told me that he is increasingly confident that autism

and other ailments are, in part, the result of the impact of

environmental chemicals on the brain as it is being formed.

“The crux of this is brain development,” he said. “If babies are

exposed in the womb or shortly after birth to chemicals that interfere

with brain development, the consequences last a lifetime.”

Concern about toxins in the environment used to be a fringe view. But

alarm has moved into the medical mainstream. Toxicologists,

endocrinologists and oncologists seem to be the most concerned.

One uncertainty is to what extent the reported increases in autism

simply reflect a more common diagnosis of what might previously have

been called mental retardation. There are genetic components to autism

(identical twins are more likely to share autism than fraternal

twins), but genetics explains only about one-quarter of autism cases.

Suspicions of toxins arise partly because studies have found that

disproportionate shares of children develop autism after they are

exposed in the womb to medications such as thalidomide (a sedative),

misoprostol (ulcer medicine) and valproic acid (anticonvulsant). Of

children born to women who took valproic acid early in pregnancy, 11

percent were autistic. In each case, fetuses seem most vulnerable to

these drugs in the first trimester of pregnancy, sometimes just a few

weeks after conception.

So as we try to improve our health care, it’s also prudent to curb the

risks from the chemicals that envelop us. Senator Lautenberg of

New Jersey is drafting much-needed legislation that would strengthen

the Toxic Substances Control Act. It is moving ahead despite his own

recent cancer diagnosis, and it can be considered as an element of

health reform. Senator Lautenberg says that under existing law, of

80,000 chemicals registered in the U.S., the Environmental Protection

Agency has required safety testing of only 200. “Our children have

become test subjects,” he noted.

One peer-reviewed study published this year in Environmental Health

Perspectives gave a hint of the risks. Researchers measured the levels

of suspect chemicals called phthalates in the urine of pregnant women.

Among women with higher levels of certain phthalates (those commonly

found in fragrances, shampoos, cosmetics and nail polishes), their

children years later were more likely to display disruptive behavior.

ly, these are difficult issues for journalists to write about.

Evidence is technical, fragmentary and conflicting, and there’s a

danger of sensationalizing risks. Publicity about fears that

vaccinations cause autism — a theory that has now been discredited —

perhaps had the catastrophic consequence of lowering vaccination rates

in America.

On the other hand, in the case of great health dangers of modern times

— mercury, lead, tobacco, asbestos — journalists were too slow to blow

the whistle. In public health, we in the press have more often been

lap dogs than watchdogs.

At a time when many Americans still use plastic containers to

microwave food, in ways that make toxicologists blanch, we need

accelerated research, regulation and consumer protection.

“There are diseases that are increasing in the population that we have

no known cause for,” said Alan M. Goldberg, a professor of toxicology

at the Bloomberg School of Public Health at s Hopkins University.

“Breast cancer, prostate cancer, autism are three examples. The

potential is for these diseases to be on the rise because of chemicals

in the environment.”

The precautionary principle suggests that we should be wary of

personal products like fragrances unless they are marked

phthalate-free. And it makes sense — particularly for children and

pregnant women — to avoid most plastics marked at the bottom as 3, 6

and 7 because they are the ones associated with potentially harmful

toxins.