Short-term Effects of Indoor Air Quality on Schoolchildren's Attention Level: A Pilot Study of Four Primary Schools in Barcelona

Abstract

BACKGROUND AND AIM: Despite knowing that children are highly sensitive towards increased pollution values, available evidence on the impact of short-term air quality exposure on children’s attention level is limited, and it overlooks indoor exposure at schools, where children spend a considerable amount of time. We aimed to investigate the relationship between short-term indoor air quality exposure at school and attention levels in schoolchildren. METHODS: A cross-sectional study of 5th grade school children (n=139, aged 9 to 11y) from four schools in Barcelona (Catalonia, Spain) was conducted in 2019, assessing attention levels via the computerized Attention Network Flanker task. Short-term indoor environmental quality was assessed, measuring Tª, relative humidity, black carbon, CO2, and PM2.5, during the test progress. Explorative linear regression models, analysing the relationship between school short-term indoor air quality exposures and attention levels were performed, adjusted by sex and selected neighbourhood contextual factors. RESULTS:Statistically significant differences were found among the four schools regarding all indoor environmental quality exposures (p-value0.001), and two attention level outcomes: impulsivity (p-value 0.048) and selective attention (p-value 0.031). Overall, no significant associations were observed between single short-term indoor quality exposures and attention level outcomes. A trend towards decreased impulsivity [-0.61 (-1.1;-0.12) 95%CI; p-value 0.014] and increased conflict score [2.45 (-7.57;12.47) 95%CI; p-value 0.63] was found with increasing Tª. A reverse trend was observed towards impulsivity [0.1 (-0.08;0.27) 95%CI; p-value 0.282] and conflict score [-1.43 (-5.04;2.18) 95%CI; p-value 0.433] with increasing relative humidity. CONCLUSIONS:Short-term indoor air quality exposures do not necessarily affect attention levels in primary school children while developing a short task. Increased indoor temperature balanced with low relative humidity could improve attention levels. Next steps will take a longitudinal approach. Including different time point measures will allow to account for temporal changes and to compare the relationship between short-term indoor quality exposures and attention levels across schools. KEYWORDS: Air pollution, Short-term exposure, Children's environmental health, Built environment, Neurodevelopmental outcomes