We all need air to breathe. But ambient air pollution — from vehicles, industrial facilities and other outdoor sources — makes that difficult.

As of 2013, almost 90 per cent of the world’s population lives in areas where outdoor air pollution exceeds the World Health Organization’s Air Quality Guideline.1

The effects are deadly. In 2016 alone, ambient air pollution killed 4.2 million people and affected the health of many more.2

A cocktail of pollutants

Ambient air pollution contains a cocktail of substances, including nitrogen oxides (NOx) and volatile organic compounds (VOCs). Those are dangerous in their own right, creating problems that range from coughing and wheezing to central nervous system problems and cancer.3,4

But the damage doesn’t stop there. When exposed to sunlight, these pollutants can create ground-level ozone: a significant contributor to asthma, respiratory diseases and other breathing problems.5

Today, more people than ever are feeling the impact. According to the Organization for Economic Co-operation and Development (OECD), the number of premature deaths caused by ambient ozone pollution increased by nearly 30 per cent between 2000 and 2015.6

Devastating smog

Hot, sunny days can also trigger photochemical reactions that transform NOX and VOCs into smog. Smog can blanket an entire region in pollution or get blown hundreds of kilometres, creating health impacts far from its original source. In fact, studies have shown that air pollution from Asia can travel across the Pacific Ocean, all the way to North America.7

Those health impacts range from minor to lethal. Smog irritates eyes, noses and throats. It aggravates heart and lung problems. Meanwhile, pregnant women exposed to ambient air pollution are more likely to have babies with low birth weights and other complications.8

Smoggy days lead to thousands of premature deaths, overload emergency rooms and make it dangerous for even healthy people to exercise outdoors. In London, nearly 9,500 people die prematurely each year because of air pollution.9 In many other countries, the toll is even higher. In Beijing, for example, breathing the smog-filled air creates the same health risks as smoking 40 cigarettes a day.10

A costly problem

Financially, air pollution costs the global economy hundreds of billions of dollars in lost labour income each year.11 Meanwhile, an OECD report estimates that global healthcare costs related to air pollution could increase eight-fold by 2060.12


2WHO. 2018. Ambient (Outdoor) Air Quality and Health. https://www.who.int/en/news-room/fact-sheets/detail/ambient-(outdoor)-air-quality-and-health




6Roy, R. and N. Braathen (2017), “The Rising Cost of Ambient Air Pollution thus far in the 21st Century: Results from the BRIICS and the OECD Countries”, OECD Environment Working Papers, No. 124, OECD Publishing, Paris. https://www.oecd-ilibrary.org/docserver/d1b2b844-en.pdf?expires=1552421681&id=id&accname=guest&checksum=AB0DD45DFA0AB3CFF217AD1B136E2606

7Toa, Z., Yu, H., Chin, M. 2015. Impact of transpacific aerosol on air quality over the United States: A perspective from Aerosol-cloud-radiation interactions. Atmospheric Environment 125, November 2015.

8Smith, R.B., Fecht, D., Gulliver, J., Beevers, S.D., Dajnak, D., Blangiardo, Marta et al. 2017. Impact of London’s road traffic air and noise pollution on birth weight: retrospective population based cohort study BMJ 359: j5299. https://doi.org/10.1136/bmj.j5299


10Rohde, R.A., Muller, R.A. 2015. Air pollution in China: Mapping of Concentrations and Sources. PLoS One. 10(8): e0135749. https://doi.org/10.1371/journal.pone.0135749

11 http://documents.worldbank.org/curated/en/781521473177013155/pdf/108141-REVISED-Cost-of-PollutionWebCORRECTEDfile.pdf

12 OECD. 2016. The Economic Consequences of Outdoor Air Pollution. http://www.oecd.org/environment/indicators-modelling-outlooks/the-economic-consequences-of-outdoor-air-pollution-9789264257474-en.htm