Thimerosal, a mercury containing preservative which was widely used but later removed from many pharmaceutical products, lingers on in some vaccines including ones injected into some of the most vulnerable recipients – pregnant women, babies, children and seniors. As of 2011, Canadian vaccines which contain thimerosal as a preservative are multi-dose vials of the influenza vaccines, Fluviral® and Vaxigrip®; Tetanus Toxoid vaccine; Recombivax HB® multi-dose vials of hepatitis B vaccine and Menomune® A/C/Y/W-135 multi-dose vials of meningococcal vaccine. Those which contain trace amounts remaining from the manufacturing process are Infanrix™-hexa (the six-valent vaccine given to babies as young as 6 months and children up to 2yrs old), Engerix®-B multi-dose vials of hepatitis B vaccine and Twinrix® hepatitis A/hepatitis B vaccine.
A 2007 statement on thimerosal by the Public Health Agency of Canada (PHAC) informs us that a considerable amount is known about methylmercury, the form of mercury found in fish but little is known about the ethylmercury from thimerosal. It admits that, compared to methylmercury, “By contrast, little is actually known about ethylmercury metabolism in humans, including whether it has the same potency as a neurotoxin, whether the blood concentration is ever significant and even whether it crosses the blood-brain barrier. It is presumed that the majority of ethylmercury metabolized from thimerosal is rapidly excreted in the stool.” Then the statement sums up with: “The risk, at best, can be described as theoretical.” We suspect that, because some of Canada’s vaccines still contain thimerosal, this sentence was meant to convey the thought that its risk is negligible or nil. Apparently, the PHAC makes the completely illogical assumption that, because nobody has bothered to thoroughly investigate possible health effects of ethyl mercury, its risk is merely “theoretical”, and therefore unlikely to exist! This assumption violates the Precautionary Principle, an ethical guideline incorporated into the Rio Declaration at the 1992 UN Conference on the Environment. This principle is often used in medicine to ensure that absence of full scientific certainty will be not be used to postpone appropriate measures against possible serious health risk.
Because science on ethyl mercury is absent, there are no established guidelines regarding exposure safe limits as there are for methylmercury. A methylmercury standard proposed by Health Canada’s Food Directorate in 1998 was a maximum daily intake of 0.20 micrograms/kg body weight and a cumulative limit of 162 micrograms. This was half as cautious as the methylmercury standard of the Environmental Protection Agency upon which the US FDA had based its request for vaccine manufacturers to phase out thimerosal.
Prior to 1994, DPT vaccines containing thimerosal were injected into children and many subsequently suffered neurological disabilities. But the 5-valent PENTA vaccine (DPT plus polio and Hib) introduced in 1994 and Pentacel (DPT, polio and Hib) introduced in 1997 contained a different preservative. The thimerosal was replaced not because of concern about mercury toxicity, but because it would have inactivated the polio portion of these new vaccines. Yet the devastating effects of mercury poisoning are well documented and have been known since the 1930′s. To protect their unborn infants from mercury poisoning, pregnant women are advised against eating fish contaminated with high levels of methylmercury and are cautioned about the risks of mercury-containing dental amalgam fillings. But despite absence of proof that ethylmercury is safe, these same women are encouraged to receive injections of mercury-containing flu shots. A synopsis of a discussion about mercury at the October 2001 US Defeat Autism Now Conference informs us: “There are many similarities in symptoms between mercury toxicity and autism, including social deficits, language deficits, repetitive behaviors, sensory abnormalities, cognition deficits, movement disorders, and behavioral problems. There are also similarities in physical symptoms, including biochemical, gastrointestinal, muscle tone, neurochemistry, neurophysiology, EEG measurements, and immune system/autoimmunity.” And now we learn of data manipulation in a Danish study which has been flaunted as indisputable evidence that thimerosal doesn’t cause autism!