Even Low Lead Exposure May Accelerate Memory Loss in Children: Study Finds

A new study published in Science Advances reveals that exposure to lead during pregnancy and early childhood may significantly speed up the rate at which children forget information. This crucial marker of memory impairment may have profound implications for learning and cognitive development in young children.

The study focused on children between ages 6 to 8 and assessed their working memory using a cognitive test called the delayed matching-to-sample task (DMTS). This test evaluates neurobehavioral functions like attention and working memory by requiring children to identify a previously seen image from multiple options after a short delay. The DMTS has already proven effective in detecting sensitivity to neurotoxicants, such as heavy metals.

Researchers examined how blood lead levels, both prenatally and during early childhood, affected memory retention. Using an advanced statistical model known as the nonlinear modified power function, the team discovered a clear link between higher childhood lead exposure (ages 4-6) and an accelerated rate of forgetting even at relatively low median blood lead levels around 1.7 µg/dL.

Importantly, the study introduces a translational approach using operant cognitive testing more commonly employed in animal toxicology studies. “Our work advances the current literature by incorporating operant tests specifically the DMTS which are commonly used in animal toxicology studies but sparse in human studies,” added Dr. Jamil M. Lane, co-first author.

The findings reinforce the urgent need for public health interventions to reduce childhood lead exposure, particularly in marginalized communities disproportionately affected by environmental hazards.

Reference: Katherine Svensson et al., Developmental Pb exposure increases rate of forgetting on a delayed matching-to-sample task among Mexican children.Sci. Adv.11,eadq4495(2025).DOI:10.1126/sciadv.adq4495