Thimerosal and autism

Blaxill MF, Redwood L, Bernard S. Thimerosal and autism A plausible hypothesis that should not be dismissed. Med Hypotheses 2004 62(5) 788 94. 

A 2004 report by the Institute of Medicine s Immunization Safety Review Committee concluded that available evidence favored rejection of a causal relation between thimerosal-containing vaccines and autism. In like manner, a recent retrospective cohort study conducted by the CDC did not support a causal association between early prenatal or postnatal exposure to mercury from thimerosal-containing vaccines and neuropsychological functioning later in childhood. 

Controversially, some have claimed a connection between the use of thimerosal in vaccines and the apparent rise in the incidence of autism. However, recent studies have shown no association between thimerosal exposure and autism. ... 

Madsen KM, Lauritsen MB, Pedersen CB, Thorsen P, Plesner AM, Andersen PH, et al. Thimerosal and the occurrence of autism Negative ecological evidence from Danish population-based data. Pediatrics 2003 112 604-6. 

Hviid A, Stellfeld M, Wohlfahrt J, Melbye M. (2003) Association between thimerosal-containing vaccine and autism. JAMA 290 1763-1766. 

Thimerosal is a preservative used in vaccines that has been purported to cause autism in children. The assumption is that thimerosal, also known as ethyl mercury, causes similar effects as methyl mercury, which has neurotoxic and nephrotoxic... 

Shevell M, Fombonne E. Autism and MMR vaccination or thimerosal exposure An urban legend Can J Neurol Sci 2006 33(4) 339-40. 

Stehr-Green P, Tull P, Stellfeld M, Mortenson PB, Simpson D. Autism and thimerosal-containing vaccines Lack of consistent evidence for an association. Am J Prev Med 2003 25 101-6. 

Ethylmercury (EtHg) is used in the form of thimerosal as a preservative in vaccines given to children. In recent years, there has been concern that EtHg exposure may induce neurodevelopmental disabilities such as language delay and attention deficit-hyperactivity disorder, but especially autism spectrum disorder. It has been removed from most vaccines in the USA and Europe but is stiU used in some developing countries. 

Psychiatric Studies of the possible relation between exposure to thimerosal in vaccines and the risk of autism continue to be published. The association has not been confirmed. For example, in a case-control study in 256 children with autistic spectrum disorder and 752 matched controls, exposure to thimerosal was not associated with an increased risk [79 ]. 

The association between exposure to thimerosal in pharmaceutical formulations and the risk of autism has been reviewed [80 ]. The author concluded that the evidence does not support such an association. This conclusion was also reached by a US court [81 ]. 

Price CS, Thompson WW, Goodson B, Weintraub ES, Croen LA, Hinrichsen VL, Marcy M, Robertson A, Eriksen E, Lewis E, Bernal P, Shay D, Davis RL, DeStefano F. Prenatal and infant exposure to thimerosal from vaccines and immunoglobulins and risk of autism. Pediatrics 2010 126(4) 656-64. 

The debate about the relation between autism and mercury (as thimerosal) in vaccines continues, without useful conclusions [37 ]. In a population-based study of the pharmacokinetics of mercury after immunization of 72 premature infants weighing 2000-3000 g at birth, the mean maximal blood mercury concentration was 3.6 fig/l, and it occurred at 1 day after immunization the maximal mean stool mercury concentration was 35 ng/g, and it occurred on day 5 urine mercury was almost undetectable [38 ]. The blood mercury half-life was 6.3 (95% Cl = 3.9S.8) days, and mercury concentrations returned to prevaccination values by day 30. The blood half-life of intramuscular ethyl mercury from thimerosal in vaccines given to premature infants is substantially shorter than that of oral methyl mercury in adults. Because of the differing pharmacokinetics, exposure guidelines based on oral methyl mercury in adults may not be accurate for children who receive thimerosal-containing vaccines. 

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