Baby teeth are helping scientists better understand autism spectrum disorders (ASD).
Baby teeth are good for more than just luring the tooth fairy; they are helping scientists better understand autism spectrum disorders (ASD).

Did you know that baby teeth act as biological libraries recording an individual's exposure to a number of different elements? Researchers are now using milk teeth to determine if a link exists between such exposures and ASD.

According to the CDC, an autism spectrum disorder currently affects as many as 1 in 68 children in the United States. Current scientific thought regarding ASD centers on genetics and environmental exposure as key factors. With the rise of autism throughout the U.S., more scientists are examining baby teeth to determine what exposures make an important impact.

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Baby teeth begin growing at the embryonic development stage; as they grow, they store traces of compounds they come in contact with. Such exposures become trapped in the teeth and act as a record of what elements the growing baby and young infant experience.

Behind a tooth's enamel is dentine. Think of dentine as ringed layers that build upon one another. Current technology developed in the United States allows researchers to examine these layers to determine what the body absorbed, and roughly when it was absorbed.

The study, funded by the National Institute of Environmental Health Sciences (NIEHS) was published in Nature Communications. It found that the baby teeth tested from children with autism showed higher levels of toxic lead and lower amounts of important nutrients such as zinc and manganese than the baby teeth of children without autism.

Data showed a notable difference in exposure to metal toxins in the last trimester and just after birth between children with and without autism.

Researchers collected data on teeth from 32 pairs of twins and 12 individual twins. Manish Arora, Ph.D., Vice Chair and Associate Professor at the Environmental Medicine and Public Health Icahn School of Medicine at Mount Sinai, led the study.

Ultimately, the research team concluded: "Significant divergences are apparent in metal uptake between ASD cases and their control siblings, but only during discrete developmental periods."

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In a press release, the NIEHS stated: "The findings…suggest that differences in early-life exposure to metals, or more importantly how a child's body processes them, may affect the risk of autism."

Researchers stated that their research should be replicated in larger studies to better understand the connection between metal exposure and autism.