Thiomersal
From RationalWiki
Thiomersal or thimerosal is a mercury-containing compound used as a preservative in many vaccines. The fact that some mercury compounds are toxic has led many to conclude that vaccines containing this compound are dangerous. Many mercury compounds--particularly those with mercury-carbon bonds--are neurotoxins, such as dimethylmercury.[1] While in large doses thiomersal can be toxic, a 2002 study indicated that the mercury levels in infants receiving a vaccine preserved by an appropriate amount of thiomersal were low; some were so low that they could not be measured. The blood concentrations were below the EPA guidelines. The amount of mercury in stool samples was high, indicating that the body eliminated the thiomersal.[2][3] Most of the concern about thiomersal derives from analogy from methylmercury, a well characterized mercury compound--but it is unclear whether the pharmacology is similar to thiomersal. Initial studies on the pharmacokinetics indicate differences.[4] Also, the amount of thiomersal actually present in vaccines is quite low. Most importantly, however, are the large studies listed here that have shown no evidence of harm.
The only routine vaccine that still contains thiomersal is the influenza vaccine, therefore arguments against other routine vaccinations should not invoke thiomersal (but often do).
[edit] See Also
[edit] References
- ↑ http://www.fda.gov/cber/vaccine/thimerosal.htm
- ↑ Pichichero ME, Cernichiari E, Lopreiato J, and Treanor J. "Mercury concentrations and metabolism in infants receiving vaccines containing thimerosal: a descriptive study." Lancet 360:1737-1741 (2002).
- ↑ http://www.niaid.nih.gov/factsheets/thimerosal.htm
- ↑ Burbacher, TM; Shen, DD; Liberato, N; Grant, K.S.; Cernichiari, E; Clarkson, T. "Comparison of Blood and Brain Mercury Levels in Infant Monkeys Exposed to Methylmercury or Vaccines Containing Thimerosal" Environmental Health Perspectives 113: 1015-1021 (2005). http://www.ehponline.org/docs/2005/7712/abstract.html
