Responding to the foolishness written by Joanna Karpasea-Jones at a "women's health site".
Holmes AS, Blaxill MF, Haley BE. (2003) Reduced levels of mercury in first baby haircuts of autistic children. Int J Toxicol. 2003 Jul-Aug;22(4):277-85.
Joanna uses this citation to make the argument:
A study in the International Journal of Toxicology found that autistic infants had reduced levels of mercury in their hair, showing that they had not been able to excrete it as effectively as infants who were neurologically normal.
Differential rates of postnatal mercury elimination may explain why similar gestational and infant exposures produce variable neurological effects ... The mothers in the autistic group had significantly higher levels of mercury exposure through Rho D immunoglobulin injections and amalgam fillings 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."
So the neurologically normal babies who had been exposed to mercury in the womb via their mother’s fillings or anti-D injections, and after birth in the form of vaccines, had a higher level of mercury showing in their hair. Autistic babies exposed to the same things did not show this same level of mercury because they hadn’t excreted it from their bodies.
Holmes et al. (2003) is one of the weakest of the weak reeds advanced for the argument "mercury exposure causes autism".
The most complete analysis of the flaws in Holmes et al. (2003) was written in 2005 by Prometheus, an academic biological scientist who blogs pseudonymously at Photon in the Darkness.
- http://photoninthedarkness.com/?p=12
- http://photoninthedarkness.com/?p=16
- http://photoninthedarkness.com/?p=17
The first flaw in the study is the authors' acceptance of the idea of "excretion into the hair". It doesn't happen. Blood mercury = hair mercury.
The second flaw is the data collection methods (the hair used in the study )
The third flaw is that the study found that the autistic children had lower hair mercury levels than the neurotypical controls. Rather than accepting that data, the authors went on to spin "tooth fairy tales" to explain why that might be so (the idea that autistic children had impaired mercury excretion). The fourth flaw in the study involves the hair analyzed: the samples had been in storage under unknown conditions for a median of five and a half years.
Do I really need to go on why Holmes et al. is a broken reed? Why Joanna should not have used this study to advance her notion that "metal metabolism disorders" are causal in autism?
I don't think so. It was, when published, a footling study, and Joanne, by citing it, revealed her lack of in serious science writing. Holmes et al. 2003 isn't even a weak reed -- it's an over-cooked noodle.
But wait: One more thing you should know: Holmes et al. 2003 authors' affiliations are given as Safeminds. Safeminds is an acronym for Sensible Action For Ending Mercury Induced Neurological Disorders. Do you think the authors had an ideological point to make?
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