New study quantifies the global health impacts of vehicle exhaust
Study links ambient PM2.5 and ozone specifically caused by vehicle exhaust emissions to ~361,000 premature deaths worldwide in 2010 and ~385,000 in 2015
On-road diesel vehicles were responsible for nearly half of the health impacts of air pollution from vehicles worldwide in 2015, and two-thirds of impacts in India, France, Germany, and Italy
The global cost of these transportation-attributable health impacts in 2010 and 2015 was approximately US$1 trillion
Exhaust from vehicles is a major source of outdoor air pollution worldwide. The health impacts are immense but unevenly distributed, both geographically and among various segments of the transportation sector, such as light-duty and heavy-duty vehicles, shipping, and off-road machinery.
A new study provides the most detailed picture available to date of the global, regional, and local health impacts attributable to emissions from four transportation subsectors: on-road diesel vehicles, other on-road vehicles, shipping, and non-road mobile engines such as agricultural and construction equipment. The study, by researchers from the International Council on Clean Transportation, George Washington University Milken Institute School of Public Health, and the University of Colorado Boulder, links state-of-the-art vehicle emissions, air pollution, and epidemiological models to estimate health impacts at the global, regional, national, and local levels in 2010 and 2015.
The study estimates that vehicle tailpipe emissions were linked to ~361,000 premature deaths from ambient PM2.5 and ozone worldwide in 2010 and ~385,000 in 2015. An estimated 70% of these impacts occurred in the four largest vehicle markets in 2015: China, India, the European Union, and the United States. Exhaust from on-road diesel vehicles was responsible for nearly half of the impacts (~181,000 premature deaths) worldwide, and fully two-thirds in India, France, Germany, and Italy. The global health burden of on-road diesel vehicles, including the PM2.5 and ozone impacts of all tailpipe emissions, is 68% higher than previously estimated for diesel NOx emissions, because it includes the effects of tailpipe PM2.5.
The distribution of health impacts and air pollution from transportation is influenced by policy, demographic, economic, and technological changes. “Transportation-attributable health impacts declined in the United States, European Union, and Japan as vehicle emission standards have been implemented, but these reductions have been offset by growing impacts in China, India, and other parts of the world,” says Susan Anenberg, lead author of the study and an associate professor at the George Washington University Milken Institute School of Public Health. “Unless the pace of transportation emission reductions is accelerated, these health impacts are likely to increase in the future as the population grows, ages, and becomes more urbanized.”
“The high public health burden of diesel vehicles in Europe underscores the need for world-class emissions standards to be accompanied by robust compliance and enforcement,” says Joshua Miller, co-author of the study and a senior researcher at the ICCT. “The long lifetime of vehicles and equipment and the increasing health burden in regions without adequate protections stress the urgency to introduce world-class standards, develop compliance programs, and adopt in-use measures that accelerate the replacement of high-emitting vehicles.”
In addition to estimated health effects on global, regional, and national scales, the study also evaluated the impacts in 100 major urban areas worldwide. The number of transportation-attributable deaths per 100,000 population in London and Paris are approximately 2 to 3 times higher than the global average.
Ambient air pollution is the leading environmental health risk factor worldwide, contributing to 3.4 million premature deaths annually from heart and lung diseases and diabetes, according to the Global Burden of Disease (GBD) study 2017. Previous studies had estimated the global health burden of emissions from all transportation sources, and from subsectors such as land transportation and shipping, in 2005, 2010, and 2014, but none had evaluated health impacts at the same level of granularity as this study.
The study assessed health impacts of transportation emissions using the GBD 2017 methods, which consider the impacts of ambient PM2.5 and ozone exposure on incidence of six disease categories. Those methods do not quantify the direct health impacts of nitrogen dioxide (NO2) exposure, which is associated with asthma incidence among children worldwide and asthma emergency department visits. However, NO2 is a precursor to both PM2.5 (in the form of nitrate aerosols) and ozone levels, so policies that target reductions in NO2—for which many European cities exceed EU air quality standards—would reduce the incidence of premature deaths from ambient PM2.5 and ozone, the health endpoints that were quantified for 2010 and 2015 in this study.
The study’s conclusions are conservative. Recent evidence indicates that the health response to PM2.5 pollution may be greater at high concentrations than previously estimated, and that air pollution may be associated with chronic kidney disease, preterm birth and other birth outcomes, and cognitive decline. Consideration of these impacts would likely increase the estimate of health impacts from vehicle exhaust emissions.
For strategies to address the health impacts of transport sector emissions, visit the ICCT Soot Free Transport Resources page at https://www.theicct.org/soot-free-transport-resources. General inquiries can also be emailed to [email protected].
A global snapshot of the air pollution-related health impacts of transportation sector emissions in 2010 and 2015
Authors: Susan Anenberg, George Washington University Milken Institute School of Public Health; Joshua Miller, International Council on Clean Transportation; Daven Henze, University of Colorado, Boulder; Ray Minjares, International Council on Clean Transportation
Contact: Joshua Miller ([email protected])