Heavy metal in children's tooth enamel: related to autism and disruptive behaviors?

Scientists shaved tiny bits of baby teeth from three groups of kids. One group had autism. One group had lots of tantrums but no autism. The last group was typically developing.

They tested the enamel for lead, mercury, and manganese. These metals can build up before birth. The team wanted to know if metal levels matched later behavior problems.

Metal levels were the same across all three groups. Kids with autism did not have more lead or mercury in their teeth. High tantrums did not link to higher metal either.

The study found no signal that heavy metals in enamel explain autism or disruptive behavior.

Lundström et al. (2014) also found no autism–behavior link. They tracked Swedish siblings and saw autism did not raise later crime risk. Both papers show autism alone does not drive externalizing problems.

Sievers et al. (2020) did find one birth risk that matters. They showed premature babies had 3.5 times higher odds of later autism or ADHD. So some prenatal events matter, but tooth metals do not.

Lung et al. (2018) and Boudreau et al. (2015) looked at assisted reproduction. Like the metal study, they found no extra autism risk from ART. The pattern is clear: many suspected birth exposures fail to predict autism once properly tested.

You can stop asking parents to test baby teeth for heavy metals. The data say it will not guide treatment. Focus your energy on evidence-based risks like prematurity and on skill-building programs that actually help.