Environmental and health benefits of mobile source and electricity generating unit policies to reduce particulate pollution

In this HEI-funded project, the investigators will build on their previous accountability analyses in Atlanta, New York, and Los Angeles to characterize the health impacts of MV and EGU policy implementation.

Poster abstract for HEI Annual Conference 2023

Environmental and health benefits of mobile source and electricity generating unit policies to reduce particulate pollution

Stefanie Ebelt, ScD¹, David Q. Rich, ScD², Howard Chang, PhD¹, Philip K. Hopke, PhD², Armistead Russell, PhD³

1.    Rollins School of Public Health, Emory University, Atlanta, Georgia
2.    University of Rochester Medical Center, Rochester, New York
3.    Georgia Institute of Technology, Atlanta, Georgia

We will characterize the health impacts of US policies targeting mobile vehicles (MV), electricity-generating units (EGU), and other pollution sources in Atlanta, New York City, and Los Angeles. Progress on each specific aim is provided below.

1. Assess and compare effects of policies targeting MV and EGU emissions on PM_2.5, PM_2.5 components, and source-specific concentrations at 6 Chemical Speciation Network monitoring sites in Atlanta, New York City, and Los Angeles during 2005-2019. We applied PMF to the available PM compositional data from the six sites, and completed trend analyses and local wind and back trajectory analyses at each site. Next, we collected and validated emissions estimates and pollutant concentrations, and developed methods to link emissions, meteorology variables, and climate variables to actual concentrations, and then developed daily counterfactual pollutant concentrations. We gathered emissions inputs, and linked emissions trends to regulatory impacts. We identified an approach to assess how regulations affected emissions in the face of changing energy costs (e.g., the reduction in natural gas prices) using a dispatch model. Last, we will examine data from additional monitoring intensives (e.g., LA-MATES, Atlanta-SEARCH) to explore spatial variability in pollutant concentrations and source impacts.
2. Assess and compare changes in PM_2.5 toxicity resulting from these policies. We are conducting epidemiologic analyses of PM_2.5 components, sources, and cardiorespiratory emergency department (ED) visits/hospitalizations at all sites. We have acquired and processed all ED/hospitalization data for the 2005-2019 period for each site, and developed daily count datasets for each outcome. For cardiovascular outcomes, we include visits resulting in a non-elective hospital admission (aged ≥18 years); for respiratory outcomes, we include visits resulting in either an outpatient ED visit or non-elective hospital admission among patients of any age. We have assessed the stability of our outcome definitions over time following changes in the International Classification of Diseases (ICD) coding (i.e., ICD-9 to ICD-10 in October 2015). We are running city-site-specific quasi-Poisson models, controlling for confounders including temperature, relative humidity, weekday, holidays, and long-term time trends. We will estimate PM effects in the early, middle, and late periods of implementation of the policies to assess potential changes in PM toxicity at each site.
3. Quantify the health benefits of these policies during 2005-2019. Using differences in concentrations between observed and counterfactual scenarios from Aim 1, and effect estimates from multipollutant epidemiologic models, we will calculate the number of ED visits/hospitalizations prevented for MV and EGU policies at each site, and assess the effect of PM_2.5 composition changes on the estimates.

      We are currently in Year 2 of a 3-year project. We will present the overarching study goals and design, and completed analyses described above.