Following last month catastrophic measures in Paris. Not a funny information, yet good to know. Air quality will undoubtedly become a very big (geo)political issue in the coming years, certainly an engineering one too.
Via Treehugger
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CC BY-ND 2.0 Flickr
The World Health Organization (WHO) released a report last year showing that air pollution killed more people than AIDS and malaria combined. It was based on 2010 figures, which were the latest available at the time. There's now a new study which looked at 2012 data, and it seems like things are even worse than we first believed.
“The risks from air pollution are now far greater than previously thought or understood, particularly for heart disease and strokes,” says Dr Maria Neira, Director of WHO’s Department for Public Health, Environmental and Social Determinants of Health. “Few risks have a greater impact on global health today than air pollution; the evidence signals the need for concerted action to clean up the air we all breathe.”
The WHO found that outdoor air pollution was linked to an estimated 3.7 million deaths in 2012 from urban and rural sources worldwide, and indoor air pollution, mostly caused by cooking (!) on inefficient coal and biomass stoves was linked to 4.3 million deaths in 2012.
Because many people are exposed to both indoor and outdoor air pollution, there is overlap in these two numbers, but the WHO estimates that the total number of victims from air pollution in 2012 was around 7 million, which is tragic since it would take relatively little in many of those cases to save livesFlickr/CC BY-SA 2.0
And it's not really a question of money, since the health costs and lost productivity caused by air pollution are higher in the long-term...
Here's how the health impacts break down for both indoor and outdoor air pollution:
Outdoor air pollution-caused deaths – breakdown by disease:
- 40% – ischaemic heart disease;
- 40% – stroke;
- 11% – chronic obstructive pulmonary disease (COPD);
- 6% - lung cancer; and
- 3% – acute lower respiratory infections in children.
Indoor air pollution-caused deaths – breakdown by disease:
- 34% - stroke;
- 26% - ischaemic heart disease;
- 22% - COPD;
- 12% - acute lower respiratory infections in children; and
- 6% - lung cancer

Wikimedia/CC BY-SA 3.0
There are lots of big obvious things we can do, such as replace inefficient and pollution small stoves in poorer countries with better stoves or even better, electric cooking. Many countries, like China, could also do a lot to cut pollution at their coal plants and over time phase out coal (which isn't just a problem for air pollution, but also for water and ground pollution and global warming). There are all these low-hanging fruits that would make a huge difference. To see how dramatic the improvement could be, just look at these photos showing how bad the situation was in the US not so long ago (China is just repeating what has gone on elsewhere...).
One thing we can do to help: plant more trees! Recent studies show that they are even better at filtering the air in urban areas than we previously thought.

© Michael Graham Richard
Via World Health Organization
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