Hair Toxic Metal Concentrations and Autism Spectrum Disorder Severity in Young Children

Previous studies have found a higher body-burden of toxic metals, particularly mercury (Hg), among subjects diagnosed with an autism spectrum disorder (ASD) in comparison to neurotypical controls. Moreover, Hg body-burden was associated with ASD severity. This cross-sectional study examined the potential correlation between hair toxic metal concentrations and ASD severity in a prospective cohort of participants diagnosed with moderate to severe ASD. The Institutional Review Board at the University of Texas Southwestern Medical Center at Dallas (Dallas, TX) approved the present study. Qualifying study participants (n = 18) were evaluated for ASD severity using the Childhood Autism Rating Scale (CARS) and quantitatively for arsenic, Hg, cadmium, lead, chromium, cobalt, nickel, aluminum, tin, uranium, and manganese using hair toxic element testing by Doctor’s Data (a CLIA-approved laboratory). CARS scoring and hair toxic element testing were blinded to one another. Increasing hair Hg concentrations significantly correlated with increased ASD severity. In contrast, no significant correlations were observed between any other of the hair toxic metals examined and ASD severity. This study helps to provide additional mechanistic support for Hg in the etiology of ASD severity, and is supported by an increasing number of recent critical reviews that provide biological plausibility for the role of Hg exposure in the pathogenesis of ASDs.

[1]  M. Desoto,et al.  Sorting out the spinning of autism: heavy metals and the question of incidence. , 2010, Acta neurobiologiae experimentalis.

[2]  Janet K. Kern,et al.  A Comparison of the Autism Treatment Evaluation Checklist (ATEC) and the Childhood Autism Rating Scale (CARS) for the Quantitative Evaluation of Autism , 2013, Journal of mental health research in intellectual disabilities.

[3]  J. Kern,et al.  Toxicity biomarkers in autism spectrum disorder: A blinded study of urinary porphyrins , 2011, Pediatrics international : official journal of the Japan Pediatric Society.

[4]  J. Kern,et al.  The biological basis of autism spectrum disorders: Understanding causation and treatment by clinical geneticists. , 2010, Acta neurobiologiae experimentalis.

[5]  J. Kern,et al.  A Prospective Blinded Evaluation of Urinary Porphyrins Verses the Clinical Severity of Autism Spectrum Disorders , 2009, Journal of toxicology and environmental health. Part A.

[6]  Janet K. Kern,et al.  Biomarkers of environmental toxicity and susceptibility in autism , 2009, Journal of the Neurological Sciences.

[7]  Salwa Tobar,et al.  Study of some biomarkers in hair of children with autism , 2011 .

[8]  Janet K. Kern,et al.  A biomarker of mercury body-burden correlated with diagnostic domain specific clinical symptoms of autism spectrum disorder , 2010, BioMetals.

[9]  Marjorie Solomon,et al.  Evidence-Based Assessment of Autism Spectrum Disorders in Children and Adolescents , 2005, Journal of clinical child and adolescent psychology : the official journal for the Society of Clinical Child and Adolescent Psychology, American Psychological Association, Division 53.

[10]  Thanaa M. Rabah,et al.  Heavy metals and trace elements in hair and urine of a sample of arab children with autistic spectrum disorder. , 2011, Maedica.

[11]  Janet K. Kern,et al.  Sulfhydryl-Reactive Metals in Autism , 2007, Journal of toxicology and environmental health. Part A.

[12]  Nancy L. Freeman,et al.  Multi-site Study of the Childhood Autism Rating Scale (CARS) in Five Clinical Groups of Young Children , 2005, Journal of autism and developmental disorders.

[13]  P. Mierzejewski,et al.  Age-dependent lower or higher levels of hair mercury in autistic children than in healthy controls. , 2010, Acta neurobiologiae experimentalis.

[14]  Janet K. Kern,et al.  Evidence of parallels between mercury intoxication and the brain pathology in autism. , 2012, Acta neurobiologiae experimentalis.

[15]  J. Kern,et al.  A Prospective Study of Oxidative Stress Biomarkers in Autistic Disorders , 2009 .

[16]  F. Montecchi,et al.  Childhood Autism Rating Scale (CARS) and Autism Behavior Checklist (ABC) Correspondence and Conflicts with DSM-IV Criteria in Diagnosis of Autism , 2004, Journal of autism and developmental disorders.

[17]  D A Bass,et al.  Trace element analysis in hair: factors determining accuracy, precision, and reliability. , 2001, Alternative medicine review : a journal of clinical therapeutic.

[18]  Erin E. Kent,et al.  Heavy Metal in Children’s Tooth Enamel: Related to Autism and Disruptive Behaviors? , 2012, Journal of autism and developmental disorders.

[19]  Sung-Hoon Kim,et al.  Porphyrinuria in Korean Children with Autism: Correlation with Oxidative Stress , 2010, Journal of toxicology and environmental health. Part A.

[20]  J. B. Adams,et al.  Mercury in first-cut baby hair of children with autism versus typically-developing children , 2008 .

[21]  Mark F Blaxill,et al.  Reduced Levels of Mercury in First Baby Haircuts of Autistic Children , 2003, International journal of toxicology.

[22]  Eric Boerwinkle,et al.  Seafood Consumption and Blood Mercury Concentrations in Jamaican Children With and Without Autism Spectrum Disorders , 2012, Neurotoxicity Research.

[23]  F. El-baz,et al.  Hair mercury measurement in Egyptian autistic children , 2010 .

[24]  Janet K. Kern,et al.  Blood mercury levels in autism spectrum disorder: Is there a threshold level? , 2010, Acta neurobiologiae experimentalis.

[25]  A. Geetha,et al.  Level of Trace Elements (Copper, Zinc, Magnesium and Selenium) and Toxic Elements (Lead and Mercury) in the Hair and Nail of Children with Autism , 2011, Biological Trace Element Research.

[26]  Lisa K. Sykes,et al.  A comprehensive review of mercury provoked autism. , 2008, The Indian journal of medical research.

[27]  Ben Alderson-Day,et al.  A Comparison of Urinary Mercury between Children with Autism Spectrum Disorders and Control Children , 2012, PloS one.

[28]  M. Obrenovich,et al.  Altered Heavy Metals and Transketolase Found in Autistic Spectrum Disorder , 2011, Biological Trace Element Research.

[29]  D. Quig,et al.  Preparation of hair for measurement of elements by inductively coupled plasma-mass spectrometry (ICP-MS) , 1998, Biological Trace Element Research.

[30]  C Lenti,et al.  Normal concentrations of heavy metals in autistic spectrum disorders. , 2012, Minerva pediatrica.

[31]  E. Geis,et al.  The Severity of Autism Is Associated with Toxic Metal Body Burden and Red Blood Cell Glutathione Levels , 2009, Journal of toxicology.

[32]  D. Austin,et al.  The plausibility of a role for mercury in the etiology of autism: a cellular perspective , 2011, Toxicological and environmental chemistry.

[33]  David Wallinga,et al.  A macroepigenetic approach to identify factors responsible for the autism epidemic in the United States , 2012, Clinical Epigenetics.