Differences in socio-demographic and environmental exposures at home vs. school in the ECHO cohort

Social and environmental exposures, typically characterized at residential locations, are linked to adverse respiratory outcomes in children; yet, children spend a significant amount of time in school. Little is known about how socio-demographic and environmental exposures vary between home and school settings.

The objectives of this study were to compare home and school exposures and to assess whether these differences were consistent across cities and varied by home-school distance.

Home and school addresses were geocoded for 6-13 year olds (n = 923) from the Environmental influences on Child Health Outcomes (ECHO) consortium. Children were drawn from cohorts located in New York City (NYC), Boston, Cincinnati, Baltimore, and St. Louis. Four categories of exposures were assessed: neighborhood socio-demographics (assigned at the census-tract level), ambient pollution (fine particulate matter (PM^2.5); 1 × 1 km grids), traffic-exposure (primary/secondary road proximity, traffic/truck density; 400 m-buffer), and green-space (Enhanced Vegetation Index; 500-m, 1500-m, and 2500-m buffer).

Overall, neighborhood socio-demographic characteristics were less favorable near home vs school including median household income ($58,125 vs $63,315), poverty (7.8% vs 5.9%), percentage of residents with less than high school education attainment (9.8% vs 8.4%), households receiving public assistance (7.6% vs 6.0%; p < 0.002 for all). Home-school differences were greatest for poverty and receiving public assistance in Baltimore (median: 48.9% and 39.3%) and St. Louis (15.8% and 15.7%), whereas the other cities showed no differences (median values of 0). Overall, children who lived farther from school (≥3.4 km), had greater differences in neighborhood socio-demographics (near vs far median percent difference: 0 vs 16.8% less than high school education, 0 vs 43.1% receiving public assistance) with the largest distance-related percent differences observed in NYC and Baltimore. No meaningful home-school differences were observed in particulate pollution, traffic-exposure, green-space (e.g., home vs school PM_2.5: 9.8 vs 9.9 μg/m³) regardless of the distance between home and school.

Children within our longitudinal birth cohorts experienced less optimal socio-demographic conditions at home compared to school, particularly those from low-income families and those traveling further to go to school; however, outdoor exposures such as PM_2.5, traffic, and green-space were similar. Our findings suggest that interventions to reduce environmental health inequities may need to address social and structural disparities at home, such as housing quality and neighborhood socioeconomic status (SES). Additionally, schools may offer an opportunity to provide beneficial exposures, potentially buffering some of the adverse SES-related exposures experienced at home. Overall, our findings provide rationale for a holistic assessment of the social and environmental exposure profile in future environmental health research.