Air pollution, health, and environmental justice implications of shifting transportation fuels

摘要

Background: Vehicles are a major contributor to air pollution health effects in the United States and globally. Air pollution exposures in the U.S. are generally higher for low-socioeconomic status (SES) than for high-SES individuals.Aims: To understand health and environmental justice aspects of alternative transportation fuels. Methods: We develop and apply a spatially and temporally explicit life cycle inventory to estimate emission changes per technology. We then use a national dispersion model (WRF/Chem; 12-km scale) to estimate impacts to ambient concentrations of fine particulate matter (PM2.5) and ozone (03). We separately estimate air pollution health impacts for white, nonwhite, high-income, and low-income individuals, for a 10% increase in vehicle-miles traveled via conventional fuel (gasoline) versus alternatives: grid-independent gasoline-electric hybrid cars, diesel cars, compressed natural gas (CNG) cars, cars fueled by ethanol from corn grain or corn stover, or battery electric vehicles powered by electricity from various fossil or non-fossil sources.Results: For scenarios with predominantly tailpipe emissions (gasoline hybrid-electric, diesel, CNG), total health impacts are reduced, but demographic aspects of exposures are unchanged (low-SES have higher exposures), relative to gasoline. For scenarios with emissions shifted up the supply chain (e.g., ethanol; vehicle electrification), health impacts are often similar to gasoline (or slightly worse), but with a demographic shift of decreasing relative impacts to low-SES individuals (i.e., helping address environmental injustice). Our research highlights the importance of considering total impacts and also distributional aspects of those impacts.Conclusions: Some of the technologies explored here would reduce total health impacts while maintaining current demographic disparities; others offer similar or slightly worse total health impacts but with reduced demographic disparities.