Air quality, energy and health
The unit provides technical support to WHO’s Member States in the development of normative guidance, tools and provision of authoritative advice on health issues related to air pollution and its sources. The unit leads monitoring and reporting on global trends and changes in health outcomes associated with actions taken to address air pollution at the national, regional and global scales.

Exposure & health impacts of air pollution

Pollutants not only severely impact health, but also the earth’s climate and ecosystems globally.

Pollutants not only severely impact health, but also the earth’s climate and ecosystems globally.

The public health impacts of air pollution exposure range from increased hospital admissions and emergency room visits, to increased risk of premature death and disease. See below to find out more about the levels of exposure and how many deaths and diseases are attributed to air pollution. Estimates are presented for ambient and household air pollution, as well as the combined effects of both household and ambient air pollution.  

Refers to the presence in the air of one or more substances at a concentration of, or for a duration above their natural levels with the potentials to produce adverse health impacts. It refers to the air pollution in the ambient environment, that is outdoor air, but able to enter homes. 

Is the air pollution generated by household fuel combustion, leading to indoor air pollution and contributing to outdoor air pollution. Household air pollution is a specific type of indoor air pollution. 

Ambient (Outdoor) Air Pollution Exposure 

Almost all of the global population (99%) are exposed to air pollution levels levels that exceed the safe WHO guideline level for fine particulate matter (PM 2.5µg/m3,), with low- and middle-income countries suffering from the highest levels of exposure.

Estimates of ambient air pollution exposure at the global, regional and national levels can be found here

Ambient (Outdoor) Pollution Disease Burden 

An estimated 4.2 million deaths globally are linked to ambient air pollution, mainly from heart disease, stroke, chronic obstructive pulmonary disease, lung cancer and acute respiratory infections. 

Worldwide ambient air pollution accounts for

43 % of deaths

and disease from chronic obstructive pulmonary disease

25 % of deaths

and disease from ischaemic heart disease

24 % of deaths

from stroke

17% of deaths

and disease from acute lower respiratory infection

29% of deaths

and disease from lung cancer

Estimates of the disease burden of household air pollution at the global, regional and national level can be found here.

Combined Ambient and Household Air Pollution Disease Burden

The combined or joint effects of ambient (outdoor) and household air pollution exposure cause about 7 million premature deaths every year from increased mortality from stroke, heart disease, chronic obstructive pulmonary disease, lung cancer and acute respiratory infections.  

How do you estimate the combined effects of household and ambient air pollution? 

Estimating the combined effects of household and ambient air pollution is not as simple as adding to the two disease burden totals together, as household air pollution smoke is not trapped inside the home. Polluting smoke can leak from windows, doors, and chimneys of homes, and spreads throughout the outdoor environment contributing to ambient air pollution levels. In some areas of the world, up to fifty percent of the ambient air pollution outdoors is caused by household air pollution entering the ambient environment.  

Accordingly, WHO uses statistical adjustments in their estimates avoid double-counting, arriving at the estimate of almost 7 million deaths a year.  

Access WHO air pollution data on burden of diseases and exposure