Autism-Mitochondrial Dysfunction Link: 1 in 200 At Risk
Posted: Mon Feb 19, 2007 11:16 am
clocker bob wrote:The responses to those two questions are the words of Dr. Laszlo Magos, author of the report, The Toxicology of Mercury, published in the New England Journal of Medicine. Maybe you've heard of that publication, Wood Goblin? It's been around a while.
I'll do you one better: I looked up the original article in NEJM. Here is the section that concerns mercury and vaccines (emphasis mine):
Thimerosal has been used as a preservative in many vaccines since the 1930s.45,46 At concentrations found in vaccines, thimerosal meets the requirements for a preservative set forth by the U.S. Pharmacopeia47 — that is, it kills the specified challenge organisms and can prevent the growth of the challenge fungi. It contains the ethyl mercury radical (CH3CH2Hg+) attached to the sulfur group of thiosalicylate and is believed to behave toxicologically like other ethyl mercury compounds. Early toxicity studies found no adverse health effects; recently, however, Ball et al. reevaluated thimerosal by applying the revised EPA guideline for methyl mercury to ethyl mercury.48 They calculated that infants undergoing the usual U.S. program of vaccines from birth to six months of age would receive more than 0.1 µg of mercury per kilogram per day.8 Steps were rapidly taken to remove thimerosal from vaccines by switching to single-dose vials that did not require any preservative. This process is now virtually complete in the United States. The decision itself is remarkable, and the speed of execution even more so49; however, the EPA guideline is based on epidemiologic data on prenatal exposure to methyl mercury rather than postnatal exposure to ethyl mercury. Ethyl mercury has some similarities to methyl mercury. They are closely related chemically, have a similar initial distribution in the body, and cause similar types of damage to the brain in toxic doses.
They also have differences. Methyl mercury is more potent. Ethyl mercury is metabolized more rapidly to inorganic mercury; perhaps this is why ethyl mercury, unlike methyl mercury, causes kidney damage in humans. Of greater importance is the recent finding that the half-life of ethyl mercury in the body is much shorter .50 The half-life of methyl mercury in blood, which is assumed to indicate the total body burden, is usually assumed to be about 50 days.51 In contrast, in children receiving thimerosal in vaccines, the half-life of ethyl mercury in blood was 7 to 10 days, or 1/7 to 1/5 as long as that of methyl mercury.50 Therefore, in the two-month periods between vaccinations (at birth and at two, four, and six months), all of the mercury should have been excreted, so that there is no accumulation.
Given the short half-life of ethyl mercury, any risks of its damaging either the brain or kidneys would seem remote. A World Health Organization advisory committee recently concluded that it is safe to continue using thimerosal in vaccines.52 This is especially important in developing countries, where the use of a preservative is essential in multidose vials. The known risk of infectious diseases far exceeds that of the hypothetical risk of thimerosal. Claims have been made that thimerosal in vaccines may be a cause of autism and related disorders, but studies testing that theory have yet to be performed.
All forms of mercury have adverse effects on health at high doses. However, the evidence that exposure to very low doses of mercury from fish consumption, the receipt of dental amalgams, or thimerosal in vaccines has adverse effects is open to wide interpretation. Moreover, attempts to reduce such exposure may pose greater health risks than those hypothesized to occur from mercury.
I only skimmed the rest of the article, but it seems that the greatest concern is being directed toward the presence of methyl mercury (as opposed to ethyl mercury, which is what WAS present in vaccines) in fish, and even this concern is based on the possibility of future problems and not on current problems (mercury poisining is, thankfully, rare).
So the good doctor actually supports my side, not yours. Thank you for providing me with some good evidence, though.