Charlie: "Swine flu the new al-Qaeda?"
Quecksilber und andere Stoffe in Impfseren unbedenklich?
Studien zum Zusammenhang zwischen Quecksilber und Autismus:
An epidemiological analysis of the ‘autism as mercury poisoning’ hypothesis
Authors David Austin1 1Life and Social Sciences, Swinburne University of Technology, Melbourne, Australia
Abstract Where direct experimental research into a causal hypothesis of a disease is impossible due to ethical and practical considerations, epidemiological inference is the accepted route to establishing cause. Therefore, to examine the autism as mercury poisoning hypothesis, this paper reviews the existing scientific literature within the context of established epidemiological criteria and finds that the evidence for a causal relationship is compelling. Exposure to mercury (via vaccines and maternal dental amalgam) in utero and during infant years is confirmed; mercury poisoning is known to cause symptoms consistent with autism; animal modeling supports the link and, critically, mercury levels are higher in both the urine and blood of autistic children than in non-autistic peers. Analogous to epidemiological evidence of the smoking–lung cancer relationship, a mercury–autism relationship is confirmed. The precautionary principle demands that health professionals not take an action if there is suspicion that the action may cause severe or lifelong health effects: it does not require certainty. Therefore, given the severity, devastating lifelong impact and extremely high prevalence of autism, it would be negligent to continue to expose pregnant and nursing mothers and infant children to any amount of avoidable mercury.
The International Journal of Risk and Safety in Medicine Volume 20, Number 3 / 2008
Mercury and autism: Accelerating Evidence?
Joachim Mutter*, Johannes Naumann*, Rainer Schneider*1, Harald Walach*1,2
& Boyd Haley3
* Institute for Environmental Medicine and Hospital Epidemiology, University Hospital Freiburg,
Germany
1 Samueli Institute, European Office, Freiburg, Germany
2 School of Social Sciences, University of Northampton, United Kingdom
3 Department of Chemistry, Lexington, University of Kentucky, USA
Abstract
The causes of autism and neurodevelopmental disorders are unknown. Genetic
and environmental risk factors seem to be involved. Because of an observed
increase in autism in the last decades, which parallels cumulative mercury exposure,
it was proposed that autism may be in part caused by mercury. We review
the evidence for this proposal. Several epidemiological studies failed to find a correlation
between mercury exposure through thimerosal, a preservative used in
vaccines, and the risk of autism. Recently, it was found that autistic children had a
higher mercury exposure during pregnancy due to maternal dental amalgam and
thimerosal-containing immunoglobulin shots. It was hypothesized that children
with autism have a decreased detoxification capacity due to genetic polymorphism.
In vitro, mercury and thimerosal in levels found several days after vaccination
inhibit methionine synthetase (MS) by 50%. Normal function of MS is crucial
in biochemical steps necessary for brain development, attention and production
of glutathione, an important antioxidative and detoxifying agent. Repetitive doses
of thimerosal leads to neurobehavioral deteriorations in autoimmune susceptible
mice, increased oxidative stress and decreased intracellular levels of glutathione in
vitro. Subsequently, autistic children have significantly decreased level of reduced
glutathione. Promising treatments of autism involve detoxification of mercury,
and supplementation of deficient metabolites.
Neuroendocrinology Letters Vol.26 No.5, October 2005
Reduced Levels of Mercury in First Baby Haircuts of Autistic Children
Amy S. Holmes Baton Rouge, Louisiana, USA Mark F. Blaxill Safe Minds, Cambridge, Massachusetts, USA Boyd E. Haley Chemistry Department, University of Kentucky, Lexington, Kentucky, USA
Reported rates of autism have increased sharply in the United States and the United Kingdom. One possible factor underlying these increases is increased exposure to mercury through thimerosal-containing vaccines, but vaccine exposures need to be evaluated in the context of cumulative exposures during gestation and early infancy. Differential rates of postnatal mercury elimination may explain why similar gestational and infant exposures produce variable neurological effects. First baby haircut samples were obtained from 94 children diagnosed with autism using Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM IV) criteria and 45 age- and gender-matched controls. Information on diet, dental amalgam fillings, vaccine history, Rho D immunoglob-ulin administration, and autism symptom severity was collected through a maternal survey questionnaire and clinical observation. Hair mercury levels in the autistic group were 0.47 ppm versus 3.63 ppm in controls, a significant difference. The mothers in the autistic group had significantly higher levels of mercury exposure through Rho D immunoglobulin injections and amalgam fillings than control mothers. Within the autistic group, hair mercury levels varied significantly across mildly, moderately, and severely autistic children, with mean group levels of 0.79, 0.46, and 0.21 ppm, respectively. Hair mercury levels among controls were significantly correlated with the number of the mothers' amalgam fillings and their fish consumption as well as exposure to mercury through childhood vaccines, correlations that were absent in the autistic group. Hair excretion patterns among autistic infants were significantly reduced relative to control. These data cast doubt on the efficacy of traditional hair analysis as a measure of total mercury exposure in a subset of the population. In light of the biological plausibility of mercury's role in neurodevelopmental disorders, the present study provides further insight into one possible mechanism by which early mercury exposures could increase the risk of autism.
International Journal of Toxicology, Vol. 22, No. 4, 277-285 (2003)
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