An international epidemiological study involving scientists from the University of Granada, published in Environment International, analysed data from a large sample of European children (13,182)
An international study in which scientists from the University of Granada (UGR) have participated has found no evidence—contrary to the findings of other studies—of a link between exposure during pregnancy and the first years of life to common air pollutants (nitrogen oxides, fine and ultrafine particles and polycyclic aromatic hydrocarbons) and symptoms of depression, anxiety, or aggressiveness in children aged between 7 and 11 years.
The research, published in Environment International, comprised an epidemiological study in which data were analysed from a large sample of children (13,182) participating in eight European birth cohorts, including the Childhood and Environment cohort (known as INMA). The INMA study covered children from different geographical areas of Spain, including Granada.
Several studies conducted in recent years have suggested that exposure to air pollution during foetal development and the early years of life could pose a risk to children’s proper neurodevelopment. Pollution has been associated, for example, with negative effects on cognitive and motor functions and with the risk of autism and attention deficit hyperactivity disorder (ADHD).
Based on this hypothesis, this study examined the possible relationship between early exposure to air pollutants and symptoms of depression, anxiety, and aggressiveness in children. While these are common behavioural–emotional problems, to date they remain under-studied in relation to foetal and childhood exposure to atmospheric pollution.
Environmental measurements
The levels of exposure to air pollutants were determined by environmental measurements taken in the areas of residence of the children in the sample, followed by the application of spatial analysis techniques. Information on symptoms of depression, anxiety, and aggressiveness was obtained through questionnaires completed by the parents.
Carmen Freire Warden of the UGR’s Environmental Medicine Research Group, one of the authors of the work, explains: “Among all the children evaluated, a total of 1,108 presented symptoms of depression and anxiety, while 870 showed signs of aggressiveness. In general, the study did not observe any significant link between antenatal or postnatal exposure and the risk of presenting symptoms of depression, anxiety, or aggressiveness, for any of the air pollutants evaluated.”
As other studies have found a relationship between exposure to air pollution and the risk of emotional and behavioural problems in adults, the absence of any link in this study could be due to the fact that the population analysed may have been too young, at between 7 and 11 years old, to have developed such problems.
“This alerts us to the need for further studies of this type but among adolescents or young adults, to corroborate the proposed hypothesis,” concludes Freire.
Bibliography:
Jorcano, A. et al., ‘Prenatal and postnatal exposure to air pollution and emotional and aggressive symptoms in children from 8 European birth cohorts’, Environment International, 131, 2019: 104927.
Media enquiries:
Carmen Freire Warden, Biomedical Research Centre (CIBM), UGR, Biohealth Research Institute in Granada (ibs.GRANADA), University Hospitals of Granada.
Tel.: +34 958 241000 (ext. 20366)
Email: cfreire@ugr.es
