Home and school pollutant exposure, respiratory outcomes, and influence of historical redlining

Abstract

Background: The discriminatory and racist policy of historical redlining in the United States during the 1930s played a role in perpetuating contemporary environmental health disparities.

Objective: Our objectives were to determine associations between home and school pollutant exposure (fine particulate matter [PM_2.5], NO₂) and respiratory outcomes (Composite Asthma Severity Index, lung function) among school-aged children with asthma and examine whether associations differed between children who resided and/or attended school in historically redlined compared to non-redlined neighborhoods.

Methods: Children ages 6 to 17 with moderate-to-severe asthma (N = 240) from 9 US cities were included. Combined home and school exposure to PM_2.5 and NO₂ was calculated based on geospatially assessed monthly averaged outdoor pollutant concentrations. Repeated measures of Composite Asthma Severity Index and lung function were collected.

Results: Overall, 37.5% of children resided and/or attended schools in historically redlined neighborhoods. Children in historically redlined neighborhoods had greater exposure to NO₂ (median: 15.4 vs 12.1 parts per billion) and closer distance to a highway (median: 0.86 vs 1.23 km), compared to those in non-redlined neighborhoods (P < .01). Overall, PM_2.5 was not associated with asthma severity or lung function. However, among children in redlined neighborhoods, higher PM_2.5 was associated with worse asthma severity (P < .005). No association was observed between pollutants and lung function or asthma severity among children in non-redlined neighborhoods (P > .005).

Conclusions: Our findings highlight the significance of historical redlining and current environmental health disparities among school-aged children with asthma, specifically, the environmental injustice of PM_2.5 exposure and its associations with respiratory health.

Keywords: Home environment; asthma disparities; asthma severity; combined home and school exposure; composite asthma severity index; lung function; school environment; traffic-related air pollution.