Childhood mental activities linked to less lead harm in later life
In adults with less childhood stimulation, 1 part per million higher second-trimester lead was linked to 0.34 standard deviations lower cognitive scores, but not with high stimulation.
In an observational cohort study, researchers analysed baby teeth and survey data from 704 adults who originally donated teeth between 1958 and 1972, tested at an average age of 62 years. Most participants (53%) were female, and they lived primarily in the St. Louis area of the United States. The team measured lead levels in baby tooth dentin to track exposure before and after birth. Participants completed six online tests to determine an overall cognitive score and recalled their engagement in cognitively stimulating activities at ages 6, 12, and 18. Childhood activities modified the link between second-trimester lead exposure and cognitive performance at age 62. Among those with less-frequent stimulating activities, each additional part per million of lead was linked to 0.34 standard deviations lower cognitive function. For those with frequent activities, the range of likely values included no difference.
Why it matters
Early lead exposure is linked to cognitive function in later adulthood. The findings support the hypothesis that engaging in cognitively stimulating activities during childhood could buffer against its deleterious effects on later adult cognitive function.
Caveats
The observational design means the findings show an association and cannot prove that childhood activities caused the difference. In addition, participants recalled their childhood activities decades later, which may introduce reporting inaccuracies.
The paper
Show 11 more authors
Tracy Punshon, Brian P Jackson, Matthew N. Barr, Felicitas B. Bidlack, Laura Germine, Scott M. Bartell, Joseph J. Mangano, Justin Farmer, Joel D. Schwartz, Rajarshi Mukherjee, Susan Korrick,Harvard University
Environmental Health Perspectives, 26 Aug 2026