Tuesday, December 14, 2004

Overloaded: Genes & Environment Report from EWG

A new report from Environmental Working Group thoroughly and readably presents much of what I've been saying about an epigenetic (genes interacting with environmental exposures) theory of autism. [Full disclosure: a friend of mine is on the board of EWG and I think they do good work on an array of issues where there is a tight coupling of environmental protection with human health.]

The whole report is available here:

For just the top line, here's the press release:

For Immediate Release: December 13, 2004

New Evidence Suggests Link Between Mercury Exposures And Autism

Scientists Identify Trait in Autistic Children That Makes Them More Susceptible To Harm From Toxic Metals

Washington, D.C., Dec. 13 -- A year-long review by Environmental Working Group (EWG) finds that a near-universal trait in autistic children suggests a possible link between autism and children's exposure to mercury. EWG's review corresponds with the publication of a new study by Dr. Jill James of the University of Arkansas for Medical Sciences. James served for fourteen years as a senior research scientist with the Food and Drug Administration and is currently Professor of Pediatrics at the University of Arkansas for Medical Sciences.

In a paper published this week in the American Journal of Clinical Nutrition, James and her colleagues identified a signature metabolic profile in autistic children that strongly suggests that these children are more susceptible to the harmful effects of mercury and other toxic chemicals.

The EWG study finds that autistic children have a common weakened ability to protect themselves from the effects of small amounts of toxic metals in their bodies. This trait appears as a severe deficit of active glutathione in autistic children when compared to healthy children. Glutathione is a potent antioxidant that is the body's most important tool for detoxifying and excreting toxic metals.

While a review published earlier this year by the National Academy of Sciences Institute of Medicine concluded that available science showed no mercury-autism link, it left open the possibility that vaccines preserved with mercury might trigger autism in a small subset of susceptible children. The new study by James and her colleagues examines precisely the issue of susceptibility in a small subpopulation.

The findings raise serious concerns about autistic children's overall exposure to environmental contaminants. Mercury is of particular significance because of its proven toxicity to the developing brain and nervous system, and its documented high exposures from a variety of sources such as canned tuna, dental fillings and vaccines preserved with mercury-based thimerosal.

This study significantly strengthens the possibility that mercury is linked to autism and other neurodevelopmental disorders. It also points to a subgroup within the population that may be vulnerable to a number of environmental contaminants.

"The autism epidemic is alerting us to the importance of individual susceptibility to environmental pollutants," said Richard Wiles, senior vice president of EWG. "Environmental safeguards that protect a theoretical 'average' person still leave thousands at risk. Increased understanding of susceptibility will provide the basis for stronger health policies that truly protect the most vulnerable."

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