Biological Trace Element Research

, Volume 163, Issue 1–2, pp 2–10 | Cite as

Levels of Metals in the Blood and Specific Porphyrins in the Urine in Children with Autism Spectrum Disorders

  • Marta Macedoni-Lukšič
  • David Gosar
  • Geir BjørklundEmail author
  • Jasna Oražem
  • Jana Kodrič
  • Petra Lešnik-Musek
  • Mirjana Zupančič
  • Alenka France-Štiglic
  • Alenka Sešek-Briški
  • David Neubauer
  • Joško Osredkar


The aim of the present study was to determine the levels of metals in blood (zinc (Zn), copper (Cu), aluminium (Al), lead (Pb) and mercury (Hg)), as well as the specific porphyrin levels in the urine of patients with autism spectrum disorder (ASD) compared with patients with other neurological disorders. The study was performed in a group of children with ASD (N = 52, average age = 6.2 years) and a control group of children with other neurological disorders (N = 22, average age = 6.6 years), matched in terms of intellectual abilities (Mann-Whitney U = 565.0, p = 0.595). Measurement of metals in blood was performed by atomic absorption spectrometry, while the HPLC method via a fluorescence detector was used to test urinary porphyrin levels. Results were compared across groups using a multivariate analysis of covariance (MANCOVA). In addition, a generalized linear model was used to establish the impact of group membership on the blood Cu/Zn ratio. In terms of blood levels of metals, no significant difference between the groups was found. However, compared to the control group, ASD group had significantly elevated blood Cu/Zn ratio (Wald χ 2 = 6.6, df = 1, p = 0.010). Additionally, no significant difference between the groups was found in terms of uroporphyrin I, heptacarboxyporphyrin I, hexacarboxyporphyrin and pentacarboxyporphyrin I. However, the levels of coproporphyrin I and coproporphyrin III were lower in the ASD group compared to the controls. Due to observed higher Cu/Zn ratio, it is suggested to test blood levels of Zn and Cu in all autistic children and give them a Zn supplement if needed.


Autism Neurodevelopmental Children Metals Zinc Copper 



This study was financed by the Slovenian Research Agency (J3-9470-0312-06). The authors thank the children who participated in the study and their parents. We also thank the staff of the Clinical Department of Child, Adolescent and Developmental Neurology for their cooperation in the study and the Kobis Company for performing the analysis of urinary porphyrins.


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Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  • Marta Macedoni-Lukšič
    • 1
    • 2
  • David Gosar
    • 1
  • Geir Bjørklund
    • 3
    Email author
  • Jasna Oražem
    • 1
  • Jana Kodrič
    • 1
  • Petra Lešnik-Musek
    • 1
  • Mirjana Zupančič
    • 1
  • Alenka France-Štiglic
    • 4
  • Alenka Sešek-Briški
    • 4
  • David Neubauer
    • 1
  • Joško Osredkar
    • 4
  1. 1.University Paediatric HospitalLjubljanaSlovenia
  2. 2.Institute of Autism Spectrum DisordersMedvodeSlovenia
  3. 3.Council for Nutritional and Environmental MedicineMo i RanaNorway
  4. 4.University Institute for Clinical Chemistry and Biochemistry, University Clinical CentreLjubljanaSlovenia

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