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Robust scientific evidence supports EPA’s new air quality standard to improve public health
The Health Effects Institute (HEI) acknowledges the decision by the U.S. Environmental Protection Agency to lower the National Ambient Air Quality Standards (NAAQS) for fine particulate matter air pollution (PM2.5) from 12 µg/m3 (micrograms per cubic meter) to 9 µg/m3. This is the first change in the PM2.5 NAAQS limits since 2012. The EPA has estimated that their decision to lower the limit may prevent as many as 4,500 premature deaths in the U.S., including many from historically marginalized and other vulnerable communities that often face the greatest risks from air pollution exposure.
HEI recently completed a comprehensive research initiative with three different studies to investigate the health effects of long-term exposure to low levels of air pollution in the United States, Canada, and Europe. Strengths of these studies included the use of unprecedented large populations – ranging from 7 million to 69 million people – with state-of-the-art exposure assessment methods and thorough statistical analyses with novel methods.
All three of HEI’s low-level studies documented positive associations between mortality and exposure to PM2.5 below 12 µg/m3, the previous U.S. National Ambient Air Quality Standard.
These low-level report findings, particularly those in the U.S. study of 68 million Medicare enrollees, played a key role in informing the new PM2.5 NAAQS in part because it was the largest and most comprehensive study to date. The U.S. study was used in the benefit assessment for the new NAAQS to calculate the expected mortality reductions in the U.S. population aged 65 or older. The U.S. study Phase 1 in 2019 was also used to evaluate the environmental justice implications of the new NAAQS. In this study, investigators found larger mortality effects from PM2.5 among older Hispanics, Asians, and particularly African Americans compared with older white adults.
In the U.S., it has been well established that low-income communities and other historically marginalized communities experience a disproportionate health burden from ambient air pollution, and other environmental and social stressors. HEI welcomes EPA’s efforts to address the challenges of air pollution-health inequalities through the NAAQS process, where additional monitors are now required to be placed in marginalized communities. HEI has recently launched a new Environmental Justice Program to better meet the needs of historically marginalized communities while addressing environmental inequities.
HEI’s research, which included rigorous peer review, provided important evidence of associations between long-term exposures to low levels of PM2.5 and health effects, suggesting that reducing air pollution below current standards could yield further health benefits and decrease air pollution-health inequalities.
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