Increased exposure to air pollution can negatively affect the brain as well as mental development of children and adolescents, finds a new study.The findings showed that air pollution increased the risk of at least one psychiatric diagnosis for children and adolescents.In particular, the concentrations of nitrogen dioxide (NO2) and particulate matter (PM10 and PM2.5) were found rampant in residential areas.The risk increased nine per cent with a 10 microgram per cubic metre higher concentration of nitrogen dioxide even after socioeconomic and demographic factors were taken into account.In addition, children and adolescents living in such areas were more likely to have been given medications, including sedatives, sleeping pills and antipsychotics, for a psychiatric disorder."The results can mean that higher concentration of air pollution, first and foremost traffic-related air pollution, may increase psychiatric disorders in children and adolescents," said lead author Anna Oudin, researcher at Umea University in Sweden.For the study, published in the journal BMJ Open, the team examined the entire under 18 population in the Swedish counties of Stockholm, Vastra Gotaland, Skane and Vasterbotten.