Racial/ethnic minority children experience greater impacts of NO2/PM10 exposures on daily/weekly asthma symptoms

Background: Previous studies demonstrate that children in racial/ethnic sub-populations have greater exposure to ambient air pollutants and experience more asthma-related adverse health outcomes. However, there is a paucity of studies investigating whether racial/ethnic minorities are more vulnerable to the effects of air pollution on asthma. This study examines the question: Are racial/ethnic populations more affected by air pollutants due to greater vulnerability?

Methods: Using Geographic Information System (GIS) software, California Health Interview Survey (CHIS) 2003 children's residential addresses were linked to government air monitoring stations for NO2 and PM10. Individual annual average pollutant exposure was estimated. Logistic regression analyses controlling for age, sex, and poverty level were performed to evaluate interactions between pollutant exposure and race/ethnicity.

Results: American Indian/Alaska Native children and Asian/PI/other children with current asthma showed greater increases in daily/weekly asthma symptoms than white children with the same increase in annual average NO2 (p < 0.001 and p=0.04, respectively). Similarly, African American and Asian/PI/other children had greater increases in daily/weekly symptoms in comparison to white children with the same level of increase in PM10 annual average concentration (p=0.03).

Conclusion: Racial/ethnic minority children experience increased odds of frequent asthma symptoms at the same level of increase in air pollutant exposures, and are therefore more vulnerable to the effects of air pollution on asthma. Health policy and community design should reflect the importance of protecting children from environmental exposures contributing to greater asthma burden, especially for these vulnerable sub-populations.