London, March 4 (IANS): Admitting your kids to schools located near busy roads or in areas with high levels of air pollution could hamper their intellectual development, new research suggests.

Attendance at schools exposed to high levels of traffic-related air pollution is linked to slower cognitive development among seven to 10-year-old children, the findings showed.

"Children attending schools with higher traffic-related air pollution had a smaller improvement in cognitive development," said Jordi Sunyer from the Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Catalonia, Spain.

The findings suggest that the developing brain may be vulnerable to traffic-related air pollution well into middle childhood, a conclusion that has implications for the design of air pollution regulations and for the location of new schools.

The researchers measured three cognitive outcomes (working memory, superior working memory, and attentiveness) every three months over a 12-month period in 2,715 primary school children attending 39 schools in Barcelona.

The increase in cognitive development over time among children attending highly polluted schools was less than among children attending school exposed to low levels of pollution, even after adjusting for additional factors that affect cognitive development, the findings showed.

Thus, for example, there was an 11.5 percent increase in working memory in a year at the lowly-polluted schools but only a 7.4 percent 12-month increase in working memory at the highly-polluted schools.

These results were confirmed using direct measurements of traffic related pollutants at schools.

"Air pollution is a suspected developmental neurotoxicant," the researchers noted.

The study appeared in the journal PLOS Medicine.