Toxicological Status of Children with Autism vs. Neurotypical Children and the Association with Autism Severity


This study investigates both the level of toxic metals in children with autism and the possible association of those toxic metals with autism severity. This study involved 55 children with autism ages 5–16 years compared to 44 controls with similar age and gender. The study included measurements of toxic metals in whole blood, red blood cells (RBC), and urine. The autism group had higher levels of lead in RBC (+41 %, p = 0.002) and higher urinary levels of lead (+74 %, p = 0.02), thallium (+77 %, p = 0.0001), tin (+115 %, p = 0.01), and tungsten (+44 %, p = 0.00005). However, the autism group had slightly lower levels of cadmium in whole blood (−19 %, p = 0.003). A stepwise, multiple linear regression analysis found a strong association of levels of toxic metals with variation in the degree of severity of autism for all the severity scales (adjusted R 2 of 0.38–0.47, p < 0.0003). Cadmium (whole blood) and mercury (whole blood and RBC) were the most consistently significant variables. Overall, children with autism have higher average levels of several toxic metals, and levels of several toxic metals are strongly associated with variations in the severity of autism for all three of the autism severity scales investigated.

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First and foremost, we thank the many autism families and their friends who volunteered as participants in this research study. We thank the Autism Society of Greater Phoenix and the Arizona Division of Developmental Disabilities for assistance with advertising this study. We thank the staff of the Southwest College of Naturopathic Medicine (N. Foster, M. Harland, B. Peterson, N. Tkacenko) for the help with phlebotomy, and we thank ICDRC for providing use of their offices for participant visits. We thank Vitamin Diagnostics and Doctor’s Data for providing testing for this study. We thank Jon Pangborn for commenting on the manuscript.

Declaration of Competing Interests

The authors declare that they have no competing interests.

Funding Acknowledgements

This work was supported by the Autism Research Institute and the Legacy Foundation.

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Correspondence to James B. Adams.

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Adams, J.B., Audhya, T., McDonough-Means, S. et al. Toxicological Status of Children with Autism vs. Neurotypical Children and the Association with Autism Severity. Biol Trace Elem Res 151, 171–180 (2013).

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  • Autism
  • Toxic metals
  • Mercury
  • Lead
  • Thallium
  • Tungsten