COLUMN -- Research bolsters autism concerns

Wednesday, April 13, 2005


In his March 29 Viewpoints column, "Rhetoric on mercury in vaccines ignores facts," State Epidemiologist Dr. Harry Hull writes that I have done readers a "great disservice" by questioning the safety of childhood vaccines and raising the biologically plausible connection between autism and the mercury-based vaccine preservative thimerosal.

"Westover clearly has not looked at all the facts and available information on the subject," Hull wrote. "The overwhelming body of scientific research says mercury in childhood vaccines does not cause autism."

Responding to the parent of an autistic daughter he wrote: "Had he [I] done a more thorough job, he would have found a substantial body of work that says that thimerosal is not the cause of autism." To confirm his assertion that vaccines play no role in autism, Hull referred the parent to a Pioneer Press article (April 3) "Study: Autistic children lack antioxidant."

Hull citing that particular study based only on a Pioneer Press article speaks volumes about the bureaucratic mindset — the tendency to use science the way a drunk uses a streetlight — for support, not for illumination.

The study referenced by Hull was conducted by researchers at the University of Arkansas and presented at the Experimental Biology 2005 Conference. The study found that a single breakdown in the body's genetic ability to produce the antioxidant glutathione might underlie many autistic symptoms, supporting the theory that autism has a genetic link.

However, the Arkansas study also supports the theory that there is a thimerosal/autism connection — analysis that did not appear in the locally edited story.

From the Los Angeles Times' original story: "The finding is suggestive, several experts said, because glutathione also is crucial for neutralizing toxic heavy metals such as mercury, which is found in food, the air and, at one time, a vaccine preservative called thimerosal."

Although published studies of autistic children have noted a lack of glutathione and published studies have found a genetic predisposition for autism, Hull obviously did not see the relationship. The Arkansas study connects the dots between genetic predisposition and a plausible environmental trigger — mercury.

"[Our findings] suggest that these kids [children with autism] would be more sensitive to an environmental exposure and would be less likely to detox from heavy metals," the study's lead author, Dr. Jill James, director of the biochemical genetics laboratory at Arkansas Children's Hospital Research Institute, said in HealthDay News.

In other words, some children cannot excrete mercury in even the "tiniest traces." as Hull characterizes levels of mercury injected into young children that are many times higher than EPA safety levels for adults.

Further, the Arkansas study should prompt reconsideration of the "overwhelming body of scientific research" demonstrating mercury is not related to autism. Large-scale epidemiological studies (like the Danish study cited in Hull's opinion piece) assume that all children have the same genetic resistance to mercury exposure. The Arkansas study strongly indicates that is a false assumption.

Another significant implication of the Arkansas study for public health: A genetic inability to excrete heavy metals identifies an epidemic-level subgroup of people at increased risk of harm (the CDC reports one case of autism in 166 live births). Policies sufficient to protect the average child from mercury exposure in vaccines might be insufficient to fully protect all children from harm.

Further, official failure to acknowledge that autistic symptoms might have a biomedical trigger discourages parents from exploring potentially beneficial medical treatment for their affected children.

To be honest, autism research and treatment still contain a great many unknowns. However, the scientific evidence of a vaccine/autism connection is substantial enough — the harm caused, the number of children at risk, the potential social costs and certainly the personal tragedy are all significant enough — that professionals we entrust with our health and safety ought to do more to ensure public trust in the vaccination program than defensively dismiss legitimate concerns.

Hull accuses me of not doing thorough research. I might listen to that criticism from the parents portrayed in David Kirby's "Evidence of Harm," who have spent years juggling care of autistic children with understanding the complexities of biochemistry; I will not accept it from a health care professional who to the parent of an autistic daughter represents a truncated newspaper article as "scientific" evidence.

I would ask: Who is it that is really doing a disservice to the public?