How the autism epidemic came to beBMJ 2011; 342 doi: https://doi.org/10.1136/bmj.d852 (Published 09 February 2011) Cite this as: BMJ 2011;342:d852
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When my son was diagnosed with autism in the mid 90s our local
education service scurried to provide any kind of service for an influx of
children who needed specialised support of a sort which had barely been
needed before in our schools, and for a group of children who could not
possibly manage without it. Ahead of them at secondary level monitored by
the same services there were only a tiny fraction of the cases (and bear
in mind Asperger type cases which might go undetected till later tend to
spin out of control at adolescence). A decade and half on we face adult
services who also have only had to deal with a tiny fraction of the cases,
and have few of the necessary resources in place.
That a psychiatrist such as Dr McClure should be reaching out to a
group of sociologists to explain away a medical phenomenon which has
substantially manifested itself during the space of his medical career is
Competing interests: Autistic son
Increases in the neurodevelopment disorder of autism, environmental toxins, toxic metals and oxidative stress
It is surprising that McClure's book review, "How the autism epidemic
came to be", does not mention the connections with increases in
In contrast, DeSoto and Hitlan's helpful review, "Sorting out the
spinning of autism: heavy metals and the question of incidence", concludes
that the increase in the neurodevelopmental disorder of autism can be
linked to toxic exposures.
A total of 17 laboratory groups(4 or more in each case) have
1 Individuals with ASD (Autism spectrum disorders) have higher
levels of neurotoxins.
2 Pockets of higher prevalence existed
3 Increased rates of ASD associated with sources of contaminants
4 Individuals with ASD have decreased detoxifying ability.
Sajdel- Sulkowska and colleagues have recently discovered brain
region-specific changes in oxidative stress marker 3-NT (3-nitrotyrosine)
and neurotrophin-3 levels in ASD in brain areas associated with speech
processing, sensory and motor coordination, emotional and social
Their exciting results match McLaren-Howard's routine analyses of
blood from 61 autistic children. He found most had deficiencies of zinc,
magnesium, chromium, selenium, manganese, molybdenum, and/or B vitamins.
Such deficiencies can impair EFA pathways. In addition, 26% (16) of the
children had DNA-adducts to malondialdehyde (from lipid peroxidation) in
their leucocytes, 20% (12) to cadmium, 15% (9) to nickel, 5% (3) to
mercury and one child had DNA-adducts to lead.3
Modern day biochemistry is much more illuminating than historical
1. McClure I. How the autism epidemic came to be. BMJ 2011; 342:d852
2. Desoto MC, Hitlan RT. Sorting out the spinning of autism: heavy
metals and the question of incidence. Acta Neurobiol Exp (Wars).
3. Sajdel-Sulkowska EM, Xu M, McGinnis W, Koibuchi N. Brain Region-
Specific Changes in Oxidative Stress and Neurotrophin Levels in Autism
Spectrum Disorders (ASD). Cerebellum. 2011 Mar;10(1):43-8.
4 Grant ECG. McLaren-Howard J. Re: The effects of toxic metals in
autistic children http://bmj.com/cgi/eletters/329/7466/588-b#74117, 13 Sep
Competing interests: No competing interests