Long-term exposure to aircraft emissions causes around 16,000 premature deaths a year, finds MIT study
Fri 7 Aug 2015 – Fine particulate matter and ozone emissions from civil aircraft are responsible for around 16,000 premature deaths annually across the world, according to a study carried out by researchers at the Massachusetts Institute of Technology (MIT) in the US. The team found the greatest impact on air quality and health was caused by emissions in the cruise phase of flights, except in Europe and North America where landing and take-off (LTO) emissions were equally as important in terms of health impact. Assigning a monetary value, it was calculated that premature deaths from long-term exposure to aviation emissions could be costed at around $21 billion a year. The researchers found that air quality costs of aviation were in the same order of magnitude as those from climate and considerably higher than costs from accidents and noise.
The study, published in Environmental Research Letters, follows an earlier assessment carried out by lead author Prof Steven Barrett and a MIT team in 2010 that looked at the incidence of premature deaths worldwide caused by emissions from jet fuel burn at cruise altitude (see article). Other studies have investigated the impact on air quality around a specific airport but this is the first to quantify the health burden accounting for near-airport (within 20km), regional and global-scale effects. Previously, according to Barrett, it was difficult to know which really mattered more – cruise emissions or airport vicinity emissions.
Aircraft emit fine particulate matter (PM2.5) that can increase rates of lung cancer and cardiovascular and respiratory disease, as well as ozone (O3), which is also linked to respiratory disease. Of these two pollutants, the vast majority of the 16,000 premature deaths (87%) could be linked to fine particulates.
In North America, LTO emissions contributed to 43% of deaths compared to those from cruise emissions, while in Europe the figure was 49% and in Asia just 9%, the difference due to population exposure to aircraft-attributable air pollution. Globally, premature deaths from LTO emissions amount to 25% of the 16,000 total.
Results from the study showed that 23% of airports have near-field population exposure to aircraft-attributable PM2.5 higher than the global average exposure, of which 17% are located in North America, 33% and 34% are located in Europe and Asia respectively, and the remaining 16% are located in other regions.
A global total of around 5,000 people who live within 20km of airports are estimated to die prematurely each year due to aviation emissions, with 38% of airport vicinity deaths in Europe, says the study. “Our results suggest, in contrast with previous analyses, that primary PM2.5 emissions from aviation are a significant contributor to health risk when airport vicinity exposure is captured,” say the researchers.
To monetise the premature deaths due to aviation emissions, the researchers determined country-specific values of statistical life. For the US, they were based on estimates from the Environmental Protection Agency, while assessments for other countries were based on national income per capita. The study shows the monetised health costs from pollution caused by aviation emissions are in the same order as aviation’s climate costs and exceed aviation’s fatal accident costs and noise costs by an order of magnitude, so roughly ten times as much.
This suggests, it states, the environmental benefits of fuel burn reduction are as much in air quality as they are in climate. Furthermore, add the researchers, this implies that when assessing the environmental impacts of aviation biofuels that result in reductions of emissions, the air quality impacts on health may be in the same order as climate impacts, since it would be expected that paraffinic biofuels would be expected to eliminate SOx emissions and reduce climate forcing black carbon (soot) emissions.
According to a study published in 2013, it is estimated around 2.1 million deaths are caused each year by human-caused increases in fine particulate matter and around 470,000 people die because of increases in ozone.
Another study has shown pollution from shipping leads to 60,000 deaths a year in the United States alone and costs up to $330 billion per year in health costs from lung and heart diseases. In Europe, academic studies put the figure at 50,000 premature deaths from international shipping emissions, with the sector likely to be the biggest single emitter of air pollution by 2020, even surpassing the emissions from all land-based sources together, says environmental NGO Transport & Environment.
“It is important to keep in mind that today aviation contributes a very small fraction to air pollution-related health risk,” Barrett told environmentalresearchweb. “However, other sectors are rapidly reducing their air pollution-relevant emissions, while aviation is forecast to double or triple by mid-century, with greater challenges in finding new ways to reduce emissions.”