Assessing Adverse Health Effects of Long-Term Exposure to Low Levels of Ambient Air Pollution: Phase 1

Research Report 200 describes the first-phase results of a study led by Dr. Francesca Dominici of the Harvard T.H. Chan School of Public Health and presents the detailed Commentary by HEI’s Low-Exposure Epidemiology Studies Review Panel on the results and the needs for further analysis.

The study evaluates the relationship between exposure to low concentrations of PM2.5 and O­3 and all-cause mortality. The team developed high resolution (1 km2) ambient concentration prediction models by combining data from a variety of sources, including satellite measurements and ground-based monitors. Health data were based on records of 61 million Medicare enrollees, between the years 2000 to 2012, which they analyzed using cohort and case crossover designs.

HEI expects — after further review by the Panel —  to publish the final Phase 2 report in 2021.

Data underlying this Phase 1 report by Dominici and colleagues are available at this time. For access to the exposure data, see Health data can be obtained from Medicare. For the statistical code, see