By Mihir Vohra, Research Associate

In the fight to end our reliance on fossil fuels, most of the focus has been on the dangers of carbon dioxide emissions, but other emissions are harmful as well. Particulate matter (PM) is a type of air pollution made up of a mixture of dust, chemicals, and liquid droplets and gets released into the air through fossil fuel combustion. When inhaled, PM enters the lungs and bloodstream, exacerbating existing respiratory tract illnesses and causing lung disease, heart disease, and lung cancer. Very small PM – called PM2.5 to denote particulate matter smaller than 2.5 micrometers in diameter – is particularly dangerous. A study published this week in Environmental Research made a shocking finding about just how dangerous this pollution is: PM2.5 emissions from fossil fuel combustion are responsible for over 20% of premature deaths worldwide.

Previous studies have calculated the effect of all sources of PM2.5 on worldwide mortality, but this is the first one with the data and computer modeling technology to accurately assess the effect of PM2.5 only from fossil fuel combustion. It incorporates fossil fuel burning from all sources and sectors such as oil and natural gas extraction, power generation, kerosene, and land, air, and sea transportation.

To do their analysis, the authors created a map of total PM2.5 emissions from all sources. They also mapped premature deaths, meaning deaths that occur before the average age of death in a given country. Then they used computer modeling to estimate PM2.5 emissions due only to fossil fuels. Using a mathematical function to calculate what percentage of premature deaths could be attributable to PM2.5 emissions, they arrived at an estimate of how many premature deaths were due to PM2.5 from fossil fuels. China and India had the highest fossil fuel PM2.5 emissions, with Europe and the United States not far behind. Unsurprisingly, these were the places with the highest death rates due to these emissions.

The study estimated that worldwide, 21.5% of all premature deaths were due to PM2.5 air pollution from fossil fuel combustion. This means that out of every five people who died before their natural lifespan, one of them died because of health effects of PM2.5 emissions from burning fossil fuels. This staggering number even surprised scientists because previous estimates using less accurate computer modeling estimated the effect to be much smaller. Overall, this study shows that a huge percentage of deaths across the globe occur because of air pollution from burning fossil fuels. Transitioning to clean fuels will have a direct impact on health and mortality worldwide.

Photo Credit: Vohra et al./Environmental Research