In a study review conducted by David A. Geier, B.A. President, MedCon, Inc., and Mark R. Geier, M.D., Ph.D. President, The Genetic Centers of America, the authors present a clear correlation between Thimerosal (a mercury based preservative used in vaccines) and spectral autism and possibly ADHD.

Thimerosal is an organic mercury compound that is metabolized to ethylmercury and thiosalicylate and has been present since the 1930s as a preservative in some vaccines and pharmaceutical products to prevent bacterial and fungal contamination.

One cited study showed that there are distinct similarities between autism and mercury exposure in their effects upon biochemistry, the immune system, the central nervous system structure, neuro-chemistry and neurophysiology

The National Toxicology Program (NTP), U.S. Department of Health and Human Services, National Institutes of Health’s National Institute of Environmental Health Sciences (NIEHS) Statement on Thimerosal states that symptoms of Thimerosal exposure include mental retardation in children, loss of coordination in speech, writing, gait, stupor, irritability, and bad temper progressing to mania.

The FDA in 1999, under the recommended childhood immunization schedule, determined infants might be exposed to cumulative doses of ethylmercury that exceed some federal safety guidelines established for exposure to methylmercury, another form of organic mercury. Additionally it was noted that routine administration of childhood vaccines expose children to more than 100 times the Federal Safety Guidelines for orally ingested methylmercury.

In another study, mice were injected with ethylmercuri-S-cysteine (EMC) and found that the extent and distribution of cell damage was highly predictable, and selective necrosis of the small granular neurons was a constant finding. Thimerosal crosses the blood-brain and placental barriers and results in appreciable mercury content in brain tissue.

In another report the authors concluded that the elimination of methyl- and ethylmercury is very slow, especially in man and primates, and consequently there is a considerable risk of mercury accumulation.

The authors also found that the glutathione system is involved in the metabolism of Thimerosal or its decomposition products. And that certain individuals are genetically more sensitive to Thimerosal due to genetic factors in their glutathione system.

Brain scans of children with autistic spectrum disorders show damage in areas similar to areas damaged by mercury. These areas tend to be areas that have minimal glutathione levels. In addition, these areas typically have higher testosterone concentrations. Testosterone has been shown to increase Thimerosal neuronal toxicity whereas estrogen has been shown to reduce Thimerosal neuronal toxicity.

According to John Hopkins University the increased incidence of ADHD could represent an alternative manifestation of vaccine-associated neuro-developmental toxicity as ADHD.

In a closed meeting where the findings of the Vaccine Safety Datalink analysis were discussed a participant, Dr. Johnston, stated: "This association leads me to favor a recommendation that infants up to two years old not be immunized with Thimerosal containing vaccines if suitable alternative preparations are available." "Forgive this personal comment, but I got called out at eight o’clock on an emergency call and my daughter-in-law delivered a son by C-Section. Our first male in the line of the next generation, and I do not want that grandson to get a Thimerosal containing vaccine until we know better what is going on."

Recent other studies report no correlation between vaccines containing mercury and autism. At least one of these studies was lead by Thomas Verstraeten, who failed to disclose to "Pediatrics" as per the journal's requirements that he is employed by GlaxoSmithKline a vaccine manufacturer that produced Thimerosal containing vaccines.

In conclusion parents taking their child for immunization should insist on vaccines that do not contain mercury preservatives, such as Thimerosal. In addition chelation and other natural detoxification programs are known to remove heavy metals from the body. Once heavy metals are removed from a child’s body it may be possible for them to recover from the affects of the poisoning.