Eighty-six studies were identified,the results of which were generally supportive of associations between exposures and worsened cognition,but the literature was varied and sometimes contradictory. There was moderate certainty support for detrimental associations between PM2.5 and general cognition in adults 40+,and PM2.5,NOx,and PM10 and executive function (especially working memory) in children. There was moderate certainty evidence against associations between ozone and general cognition in adults age 40+,and NOx and reasoning/IQ in children. Some associations were also supported by meta-analysis (N = 14 studies,all in adults aged 40+). A 1 ?g/m3 increase in NO2 was associated with reduced performance on general cognitive batteries (? = ?0.02,p < 0.05) as was a 1 ?g/m3 increase in PM2.5 exposure (? = ?0.02,p < 0.05). A 1?gm3 increase in PM2.5 was significantly associated with lower verbal fluency by ?0.05 words (p = 0.01) and a decrease in executive function task performance of ?0.02 points (p < 0.001).
Back to top