According to a growing study, exposure to air pollution in the earliest stages of life is associated with adverse effects on cognitive abilities. Led by the Barcelona Institute for Global Health (ISGlobal), a center supped by "la Caixa", the new study has offered new data: exposure to particulate matter with a diameter of fewer than 2.5 μm (PM2.5) during pregnancy and the first years of life is connected with a reduction in fundamental cognitive abilities, such as working memory and executive attention.
As part of the BREATHE project, the research has been published in Environmental Health Perspectives. The study's objective was to build on the knowledge generated by earlier studies carried out by the same team, which discovered lower levels of cognitive development in children attending schools with higher levels of traffic-related air pollution.
The team investigated 2,221 children between seven and ten years of age attending schools in the city of Barcelona. The children's cognitive abilities were assessed using various computerized tests. Exposure to air pollution at home during pregnancy and throughout childhood was estimated with a mathematical model using real measurements.
The study discovered that greater PM2.5 exposure from pregnancy until age seven years was connected with lower working memory scores on tests administered between the ages of seven and ten years. The findings suggest that exposure to fine particulate matter throughout the study period had a cumulative effect, although the association was stronger when the most recent years of exposure were taken into account. Working memory is a cognitive system responsible for temporarily holding information for subsequent manipulation. It plays a fundamental role in learning, reasoning, problem-solving, and language comprehension.
Analysis of sex-stratified revealed that the relationship between PM2.5 exposure and diminished working memory was discovered only in boys. The lead author of the study and ISGlobal researcher, Ioar Rivas said that as yet, they don't understand what causes these differences, but there are various hormonal and genetic mechanisms that could lead to girls having a better response to inflammatory processes triggered by fine particulate matter and being less susceptible to the toxicity of these particles.
Also, the study discovered that higher exposure to particulate matter was associated with a reduction in executive attention in both boys and girls. Executive attention is one of the three networks that make up a person's attention capacity. It is involved in high-level forms of attention, including the detection and resolution of conflicts between options and responses, error detection, response inhibition, and the regulation of thoughts and feelings.
The Childhood and Environmental Programme Coordinator at ISGlobal and last author of the study, Jordi Sunyer said that this research reinforces scientists' previous findings and confirms that exposure to air pollution at the beginning of life and throughout childhood is a threat to neurodevelopment and an obstacle that prevents children from reaching their full potential.
