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Could Endocrine-Disrupting Chemicals in Vaccines Cause Autism?

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In a recent Huffington Post article, "Cracking the Autism Riddle: Toxic Chemicals, a Serious Suspect in the Autism Outbreak" (6/30/09), Dr. Harvey Karp gives credence to the theory that environmental chemicals cause autism.

Dr. Karp correctly observes, "research has mounted against a virtual police lineup of EDCs, like BPA (in food cans, hard plastic water bottles), phthalates (in soft plastics, cosmetics) and fire retardants (in sofas, computers, flame-resistant clothing)." He later writes, "Furthermore, since multiple different EDCs have the same effect on the developing body, exposure to a variety of EDCs may create a large cumulative stress to the body."

Environmental "triggers," including endocrine-disrupting chemicals (EDCs), is an area in which autism organizations are seeking to encourage further research and it continues to be under-studied as a mechanism of autism causality.

So how should we study a potential link between EDCs and autism?

Perhaps this is too obvious, but why not examine what most normally developing children who are later diagnosed with autism have in common? Why not study the EDCs in childhood vaccines?

That's right, most vaccines contain aluminum adjuvants used to increase immune response, and aluminum is an endocrine-disrupting chemical. Like it or not, vaccines are likely the largest source of one-time exposure to endocrine-disrupting chemicals in early infant development.

In addition, some vaccines still contain mercury as a preservative, and mercury is also a known EDC as well as a developmental neurotoxin. The seasonal influenza vaccine contains as much as 25 mcg of mercury, exceeding federal safety guidelines established by the EPA.

There is a long list of research demonstrating mercury's effect as an endocrine-disrupting chemical, as referenced in the paper authored by Dr. Tan of the EPA in March 2009 (Tan, Shirlee W., Meiller, Jesse C. and Mahaffey, Kathryn R., "The endocrine effects of mercury in humans and wildlife," Critical Reviews in Toxicology,39:3,228-269).

The start of the autism epidemic correlates closely with the phased introduction of the Hib vaccine plus the HepB vaccine in the late 1980's/early 1990's. At that time, both the Hib and the HepB contained high amounts of mercury and aluminum which significantly increased the exposure to infants to both of these toxic chemicals at a far earlier age than ever before (HepB: at birth and then 1-2, 4, and 6 months; Hib: 2, 4, and 6 months).

Although mercury has been reduced or removed in some vaccines since 2003, mercury is still a component in most flu vaccines. The number of infant vaccines with aluminum-based adjuvants administered by 18 months of age has increased by 54% since 2000, and the amount of aluminum administered has increased by 23%.

In an article for Mothering Magazine, Dr. Bob Sears warned about the aluminum content found in infant vaccines:

In other words, a newborn who gets a Hepatitis B injection on day one of life would receive 250 mcg of aluminum. This would be repeated at one month with the next Hep B shot. When, at two months, a baby gets its first big round of shots, the total dose of aluminum could vary from 295 mcg (if a non-aluminum HIB and the lowest-aluminum brand of DTaP are used) to a whopping 1225 mcg (if the Hep B vaccine is given along with the brands with the highest aluminum contents). These doses are repeated at four and six months. With most subsequent rounds of shots, a child would continue to get some aluminum throughout the first two years. But the FDA recommends that premature babies, and anyone with impaired kidney function, receive no more than 10 to 25 mcg of injected aluminum at any one time.

Interestingly, Dr. Karp also refers to how slightly elevated levels of testosterone in fetuses have been linked to autism, and that autism-type disorders are four to nine times more common in boys.

Research indicates that mercury and aluminum components of vaccines may have synergistic toxicity with testosterone.

So there you have it, aluminum and mercury are both endocrine disrupters, as well as neurotoxins, and both can be particularly toxic when exposed to testosterone.

With all of this in mind, it is important to note that in May 2009, HHS Secretary Kathleen Sebelius directed approximately $1 billion to be used for the development of an H1N1 vaccine and for clinical studies to determine dose level and assess the safety and effectiveness of potential vaccines. The funds will be used to place additional orders for bulk H1N1 antigen and adjuvant on existing contracts with Sanofi Pasteur, MedImmune, GlaxoSmithKline and Novartis. The vaccine ingredients will become a part of the pandemic stockpile, for use if a vaccination campaign is necessary.

Antigen is the active ingredient in a vaccine that causes the human body's immune system to develop antibodies that help fight an invading virus. Depending on the results of clinical studies, adjuvant could be added to a vaccine to boost the immune system's response, and potentially reduce the amount of antigen necessary for the body to recognize and fight a virus.

As I mentioned earlier, aluminum is often used as an adjuvant in vaccines. Many U.S. licensed children's vaccines contain aluminum, including:
  • DTaP (diphtheria-tetanus-acellular pertussis) vaccine
  • Hepatitis B vaccines
  • Hepatitis A vaccines
  • Some Hib (Haemophilus influenzae type b) conjugate vaccines
  • Human Papillomavirus vaccine
  • Prevnar (Pneumococcal) vaccine
  • Tdap (tetanus-diptheria-acellular pertussis) adolescent vaccine

In June, the National Vaccine Advisory Committee (NVAC) issued a report reviewing the Centers for Disease Control's Immunization Safety Office Draft Research Agenda. The NVAC report identified critical gaps in vaccine safety research and made sweeping recommendations -- one of those critical gaps -- data on simultaneous administration of multiple vaccines.

There is a growing recognition that even small amounts of endocrine-disrupting chemicals can have a deleterious affect on the development of the fetus, infants and young children. It is logical that we include the EDCs used in vaccines, along with other neurotoxins, and consider, as Dr. Karp suggests, the "cumulative stress" these chemicals might create.

It remains unclear how the H1N1 vaccine will be given (with other vaccines, or separately) and what amount of EDCs will be used in the formulations. It is also unclear if another adjuvant, squalene, used in the Anthrax vaccine and believed to be linked to Gulf War Syndrome, will also be an ingredient. This has many parents and physicians rightfully concerned.

One thing seems clear: sufficient safety data will not be available before the H1N1 vaccination campaign is scheduled to start and pregnant women and young school age children are the high priority target population. This means more chemical exposures during critical periods of development.

It is encouraging to read that Dr. Karp is now joining a growing number of professionals who support new studies into the autism risk in vaccinated vs. unvaccinated kids and the metabolism of vaccine ingredients like aluminum.

If indeed endocrine-disrupting chemicals can be linked to autism, then health officials should be implementing whatever policies are necessary that will eliminate these exposures and not be initiating plans that will increase the exposures.

Why is something that seems to be so fundamentally obvious so difficult for some health officials to understand?

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