Biological Trace Element Research

, Volume 151, Issue 2, pp 181–186 | Cite as

Levels of Heavy Metals and Essential Minerals in Hair Samples of Children with Autism in Oman: a Case–Control Study

  • Yahya M. Al-Farsi
  • Mostafa I. Waly
  • Marwan M. Al-Sharbati
  • Mohammed A. Al-Shafaee
  • Omar A. Al-Farsi
  • Maha M. Al-Khaduri
  • Ishita Gupta
  • Allal Ouhtit
  • Samir Al-Adawi
  • Mona F. Al-Said
  • Richard C. Deth


Toxic levels of heavy metals and low levels of essential minerals have been suggested to play a critical role in the pathogenesis of autism spectrum disorders (ASD). This study documents the levels of heavy metals and essential minerals in hair samples of children with ASD in Muscat, the urbanized capital of Oman, Muscat. The study included 27 children with ASD and 27 matched non-ASD controls. Parental interviews were held and dietary intake questionnaires completed in conjunction with the collection of hair samples. Analysis of heavy metals and essential minerals was carried out by inductively coupled plasma mass spectrometry. Chi-square analysis and non-parametric Fisher’s exact tests were used to assess statistical significance. Children with ASD had significantly higher levels of all 11 analyzed heavy metals in their hair samples (P < 0.05), ranging from 150 to 365 % of control levels. ASD children also had significantly higher levels of essential minerals sulfur, sodium, magnesium, potassium, zinc, and iron, but lower levels of calcium and copper in their hair samples. This study corroborates data from previous studies in different parts of the world indicating the presence of elevated levels of heavy metals and selective depletion of essential minerals in the hair of children with ASD.


Autism Heavy metals Essential minerals Hair Oman Case–control 


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Copyright information

© Springer Science+Business Media New York 2012

Authors and Affiliations

  • Yahya M. Al-Farsi
    • 1
    • 7
    • 10
  • Mostafa I. Waly
    • 2
    • 8
  • Marwan M. Al-Sharbati
    • 3
  • Mohammed A. Al-Shafaee
    • 1
  • Omar A. Al-Farsi
    • 1
  • Maha M. Al-Khaduri
    • 4
  • Ishita Gupta
    • 5
  • Allal Ouhtit
    • 5
  • Samir Al-Adawi
    • 3
  • Mona F. Al-Said
    • 6
  • Richard C. Deth
    • 9
  1. 1.Department of Family Medicine and Public Health, College of Medicine and Health SciencesSultan Qaboos UniversityAl-KhoudhOman
  2. 2.Department of Nutrition and Food Sciences, College of Agriculture and Marines SciencesSultan Qaboos UniversityMuscatOman
  3. 3.Department of Behavioural Medicine, College of Medicine and Health SciencesSultan Qaboos UniversityMuscatOman
  4. 4.Department of Obstetrics and Gynecology, College of Medicine and Health SciencesSultan Qaboos UniversityMuscatOman
  5. 5.Department of Genetics, College of Medicine and Health SciencesSultan Qaboos UniversityMuscatOman
  6. 6.Department of Early Childhood Education, College of EducationSultan Qaboos UniversityMuscatOman
  7. 7.Department of Epidemiology, School of Public HealthBoston UniversityBostonUSA
  8. 8.Department of Nutrition, High Institute of Public HealthAlexandria UniversityAlexandriaEgypt
  9. 9.School of Pharmacy, Bouvé College of Health SciencesNortheastern UniversityBostonUSA
  10. 10.Department of Family Medicine and Public Health, College of Medicine and Health SciencesSultan Qaboos UniversityAl-KhoudhSultanate of Oman

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