P3.E091: Quantifying the Association between Low-Level PM2.5 Air Pollution and IQ Loss in Children

Background: Airborne particulate matter pollution (PM2.5) poses severe risks to human health. PM2.5 exposures are linked to adverse outcomes in multiple organs, including the brain and nervous system. The burden of PM2.5-related disease is greatest in minority and marginalized populations. Of particular concern are the effects on children. This systematic review aims to quantify the association between ambient PM2.5 air pollution and loss of cognitive function in children through a systematic review of the literature linking low-level PM2.5 exposures with decreased Intelligence Quotient (IQ) scores.

Methods: Following PRISMA guidelines, we conducted a systematic literature search across 7 databases. We identified 1,107 unique studies that appeared to link PM2.5 exposure with IQ loss in children. Five of these studies met our search inclusion criteria and were included in the final analysis.

Results: Each study in our final analysis reported a negative association between PM2.5 exposure and children’s IQ. Using the data in these studies, we calculated correlation coefficients relating 1µg/m3 increments in PM2.5 exposure with loss of Full-Scale IQ., Verbal IQ, and Performance IQ. To develop combined estimates from these concentration-response functions, we weighted each estimate by sample size. We found that each 1µg/m3 increase in PM2.5 concentration is linked with the loss of an estimated 0.24 FSIQ points, 0.40 PIQ points, and 0.20 VIQ points.

Conclusion: This systematic review finds clear and consistent evidence for an association between PM2.5 air pollution exposure in early life and children's cognitive function loss. The strongest negative association appears to be with PIQ. This analysis will enable estimation of the burden of cognitive loss in pediatric populations exposed to PM2.5 air pollution.