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Road transportation and power plants are the leading causes of air-pollution-related deaths in the US, contributing to 53,000 and 52,000 early deaths respectively each year.
Researchers from Massachusetts Institute of Technology (MIT) estimate that total combustion emissions in the United States account for about 200,000 premature deaths per year in the country due to changes in particulate matter (PM2.5) concentrations, and about 10,000 deaths due to changes in ozone concentrations.
The group tracked emissions from sources such as industrial smokestacks, vehicle tailpipes, marine and rail operations, and commercial and residential heating throughout the country.
In a state-by-state analysis, it was found that California suffers the worst health impacts from air pollution, with about 21,000 early deaths annually, mostly attributed to road transportation and to commercial and residential emissions from heating and cooking.
When mapping local emissions in 5,695 cities, the highest emissions-related mortality rate was found in Baltimore, where 130 out of every 100,000 residents likely die in a given year due to long-term exposure to air pollution.
“In the past five to ten years, the evidence linking air-pollution exposure to risk of early death has really solidified and gained scientific and political traction,” said Steven Barrett at MIT. “There’s a realization that air pollution is a major problem in any city, and there’s a desire to do something about it.”
According to Barrett, a person who dies from air-pollution causes typically dies about a decade earlier than he or she might have otherwise.
The greatest number of emissions-related premature deaths came from road transportation, with 53,000 early deaths per year attributed to exhaust from cars and trucks.
Pollution from electricity generating power plants accounted for 52,000 premature deaths annually. The largest impact was seen in the east-central United States and in the Midwest.
To explain why road transport contributes more than power plants to the health damage, the researchers reasoned that “vehicles tend to travel in populated areas, increasing large populations’ pollution exposure, whereas power plants are generally located far from most populations and their emissions are deposited at a higher altitude.”
Most premature deaths due to commercial and residential pollution sources, such as heating and cooking emissions, occurred in densely populated regions along the east and west coasts.
Pollution from industrial activities was highest in the midwest, roughly between Chicago and Detroit, as well as around Philadelphia, Atlanta and Los Angeles. Industrial emissions also peaked along the Gulf Coast region, possibly due to the proximity of the largest oil refineries.
Southern California saw the largest health impact from marine-derived pollution, such as from shipping and port activities, with 3,500 related early deaths.
While the study is based on emission data from 2005, Barrett says the results are likely representative of today’s pollution-related health risks.
Christer Ågren
The results of the study “Air pollution and early deaths in the United States. Part I: Quantifying the impact of major sectors in 2005” are published in the journal Atmospheric Environment. Link:
Source: MIT News, 29 August 2013
