Indoor-outdoor relationships of airborne nanoparticles, BC and VOCs at rural and urban preschools

Health risks caused by exposure to black carbon (BC) and nanoparticles (NP) are well studied, although no standard currently exists for them worldwide. Exposure children may lead serious health effects due their increased vulnerability longer time spend inside the classrooms, making it important assess factors that affect air quality in preschools. Thus, this work aims evaluate indoor-outdoor (I/O) relationships of NPs 10–420 nm range, BC volatile organic compounds (VOCs) at rural urban preschools (aged 3–5 years) between May 2016 July 2017. Factorial analysis was applied identify possible emission sources. Prior communalities were estimated squared multiple correlations with all other variables. We used varimax rotation method criterion factor selection number eigenvalues greater than one. Results indicate NP 4- 3.2-times higher outdoor traffic emissions, respectively. Highest concentrations occurred during rush hours pickup children. In school, directly related accumulation mode (N49-205), while area, local particles from pulp industries regional background. Nucleation (N11-36) emissions school secondary formation particles. Mean I/O ratios (0.54; 0.51) (0.71; 0.91) schools, respectively, suggested outdoors. VOCs indoor (I/O = 1.97) 2.22) sites, indicating these pollutants generated inside, regardless or sites. These findings suggest necessity improving ventilation commuting styles lower around environments.