Traffic Pollution Slows Down Cognitive Development in Grade Schoolers

The location of schools in areas with high levels of air pollution may have an impact on the cognitive development of students in their middle childhood. A new study by the Centre for Research in Environmental Epidemiology (CREAL) in Spain assessed the cognitive skills of primary school students in Barcelona attending schools exposed to traffic-related air pollution.

Cognitive outcomes of 2,715 grade schoolers attending 39 schools were measured after every quarter over a period of 12 months. These were based on attentiveness, working memory and superior working memory. The children were classified into two groups – those attending schools highly exposed to air pollution and students who were attending schools with low exposure to air pollution. The research team made sure that the schools had similar socio-economic conditions. Levels of traffic-related pollutants were also measured in the areas.

After making a comparison of the outcomes, the researchers, led by Jordi Sunyer, found that cognitive development among children frequently exposed to polluted air was less compared with students who had less exposure to air pollutants. Working memory, one of the skills evaluated in this study, helps children retain information, concentrate on learning, comprehend and solve problems. Over the 12-month period, working memory improved by 11.5 percent in less polluted schools, while there was only 7.4 percent increase in the schools greatly exposed to air pollution.

Results of the study published in the March issue of PLOS Medicine imply that exposure to traffic-related air pollution may delay coognitive development during middle childhood. Thus, school locations and the air quality are some of the factors that can be considered in establishing new learning institutions. The accuracy of the findings may be limited by some unidentified factors that may have also contributed to the participants’ cognitive development.

Prior studies on the health effects of childhood exposure to traffic pollution have associated increased risk in some disorders and diseases such as allergies, asthma, other respiratory problems, obesity, and metabolic disorders. These studies also suggest measures to reduce and control traffic pollution, especially in schools, park and playgrounds, or places where children spend most of their time.