Baby Teeth, Used As a Biomarker, Link Autism With Toxic Lead
June 1, 2017 - Baby teeth from children with autism contained more toxic lead and less of the essential nutrients zinc and manganese, compared to teeth from children without autism. Using naturally shed baby teeth, layers of dentine, the hard substance beneath tooth enamel, was analyzed in ways that corresponded to different developmental periods. This innovative NIEHS-funded study suggests that differences in early-life exposure to metals, or more importantly how a child’s body processes them, may affect the risk of autism.
The researchers observed higher levels of lead in children with autism throughout development, with the greatest disparity observed during the period following birth. They also observed lower uptake of manganese in children with autism, both before and after birth. The pattern was more complex for zinc. Children with autism had lower zinc levels earlier in the womb, but these levels then increased after birth, compared to children without autism.
The method of using baby teeth to measure past exposure to metals holds promise for examining environmental factors associated with other disorders, such as attention deficit hyperactivity disorder.
Arora M, Reichenberg A, Willfors C, Austin C, Gennings C, Berggren S, Lichtenstein P, Anckarsater H, Tammimies K, Bolte S. 2017. Fetal and postnatal metal dysregulation in autism. Nat Commun; doi: 10.1038/NCOMMS15493 [Full text]
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