The pre-teen years are critical to development and health for many reasons. Precisely a recent study by the Barcelona Institute of Global Health (ISGlobal), a center promoted by Obra Social La Caixa, reveals that continuous exposure to polycyclic aromatic hydrocarbons (HPA) – even at levels lower than the limits established by the European Union – During preadolescence it is associated with changes in the caudate nucleus of the brain . The research has been published in the journal Environment International and focuses on these substances (HPA) that are very present in today’s cities due to traffic. HPAs are air pollutants that come from the incomplete combustion of organic matter , especially fossil fuels such as oil, biomass, and other sources, such as tobacco smoke, barbecued cooking, and barbecues .
The main source of emission of these substances in cities such as Madrid or Barcelona, where the study was carried out, is the circulation of vehicles. In previous research, these compounds had been linked to attention deficit hyperactivity disorder (ADHD) in children who had been exposed to PAHs in the prenatal phase. The new study, which is part of the BREATHE project, measured pollution levels in 39 schools in Barcelona and took magnetic resonance images of 242 boys and girls aged 8 to 12, who also carried out tests to assess possible symptoms of ADHD .
The aim was to investigate the effects that exposure to HPA can have on the volume of the infantile basal ganglia and its possible relationship with ADHD . It had already been observed in other studies that the brain structure of children with hyperactivity had a reduced volume. Everything seems to indicate, in the opinion of Marion Mortamais, researcher at ISGlobal and lead author of the study, that the inhalation of HPA, especially benzopyrene, influences the reduction of the volume of the caudate nucleus .
An increase of 70 pg / m3 in the interior and exterior concentration of benzopyrene is associated with a reduction of almost 2% in the volume of this nucleus. However, this is a subclinical reduction, since it does not seem to necessarily imply that ADHD symptoms are present. But as Marion Mortamais told the SINC agency, “in any case, given the involvement of the caudate nucleus in many crucial cognitive and behavioral processes, its reduction in volume is of concern for infant neurodevelopment .” For Jordi Sunyer, head of the ISGlobal Children’s Health program and professor at Pompeu Fabra University (UPF), “these results are added to the abundant scientific evidence that underlines the urgent need to reduce air pollution , particularly that from traffic , and suggest the convenience of re-evaluating the annual maximums established by European regulations “.
