Do low-income adults and children have greater pollutant exposure?

Background: In 1994, an Executive order was issued to address environmental justice in minority populations and low-income populations. It is important to examine if low-income populations still carry a greater burden of air pollution exposures. Using government air monitoring data, this study aims to examine if low-income Californians with asthma or asthma-like symptoms have greater exposure to air pollutants.

Methods: We linked data from the 2003 California Health Interview Survey (CHIS) and government air monitoring stations. Using Geographic Information Systems (GIS), CHIS respondents were linked to a station within 5-miles of their residential addresses. Annual pollutant averages were calculated from the 12-months prior to the CHIS interview. We performed t-tests on mean exposure estimates to identify disparities across income levels.

Results: Adults and children with current asthma living below 200% of Federal Poverty Level (FPL) have higher estimates for NO2, PM10, and PM2.5 compared to those living at or above 400% of the FPL (p < 0.05). Adults with asthma-like symptoms living below 200% of the FPL had higher estimates for NO2, PM10, and PM2.5 (p < 0.001), and children with asthma-like symptoms living below 200% of the FPL had higher estimates for PM2.5 (p < 0.05) compared to those living above 400% of the FPL.

Conclusions: Disparities in annual pollutant exposures exist among low-income California populations, both with current asthma and with asthma-like symptoms. The unequal distribution of air pollutant exposures suggest more must be done to regulate and reduce emissions in low-income communities to better protect the health of these communities over-burdened by pollution.