Early life exposure to airpollution poses a significant risk to brain development from direct exposure to toxicants or via indirect mechanisms involving the circulatory, pulmonary or gastrointestinal systems. In children, exposure to traffic relatedairpollution has been associated with adverse effects on cognitive, behavioral and psychomotor development.
We aimed to determine whether childhood exposure to traffic relatedairpollution is associated with regional differences in brain volume and corticalthickness among children enrolled in a longitudinal cohort study of traffic relatedairpollution and child health. We used magnetic resonance imaging to obtain anatomical brain images from a nested subset of 12 year old participants characterized with either high or low levels of traffic relatedairpollution exposure during their first year of life.
We employed voxel-based morphometry to examine group differences in regional brain volume, and with separate analyses, changes in corticalthickness. Smaller regional graymatter volumes were determined in the left pre- and post-central gyri, the cerebellum, and inferior parietal lobe of participants in the high traffic relatedairpollution exposure group relative to participants with low exposure. Reducedcorticalthickness was observed in participants with high exposure relative to those with low exposure, primarily in sensorimotor regions of the brain including the pre- and post-central gyri and the paracentral lobule, but also within the frontal and limbic regions.
These results suggest that significant childhood exposure to traffic relatedairpollution is associated with structural alterations in brain.