What is the current state of air quality around the world?
The world’s population does not have equal access to clean air.
When characterizing ambient (outdoor) air quality for its potential impact on people’s health, scientists are most interested in the levels of pollution close to areas with large numbers of people. They therefore estimate average concentrations of fine particulate matter (PM2.5) and ozone that are population-weighted. This means that the averages reflect greater weight, or emphasis, given to air pollution concentrations in areas of high population density, where the most people live. These weighted numbers make it easier to compare average pollution concentrations across countries.
Current PM2.5 levels
The first map (see below) shows population-weighted annual average concentrations of fine particulate matter around the world in 2016. The highest concentrations were in countries in North Africa (e.g., Niger at 204 µg/m3 and Egypt at 126 µg/m3), West Africa (e.g., Cameroon at 140 µg/m3 and Nigeria at 122 µg/m3), and in the Middle East (e.g., Saudi Arabia at 188 µg/m3 and Qatar at 148 µg/m3).
The high ambient concentrations in these regions were due mainly to windblown mineral dust. However, in some of these countries (for example, Niger, Nigeria, and Cameroon), high proportions of the population burn solid fuels in the home and may also engage in open burning of agricultural lands or forests, both of which can also contribute substantially to air pollution outdoors.
The next-highest concentrations appeared in South Asia where combustion emissions from multiple sources, including household solid fuel use, coal-fired power plants, agricultural and other open burning, and industrial and transportation-related sources, are the main contributors. The population-weighted annual average PM2.5 concentrations were 101 µg/m3 in Bangladesh, 78 µg/m3 in Nepal, and 76 µg/m3 in both India and Pakistan. China’s population-weighted annual average concentration was 56 µg/m3 in 2016.
The lowest population-weighted annual average PM2.5 concentrations (about 8 µg/m3 or less) were in Australia, Brunei, Canada, Estonia, Finland, Greenland, Iceland, New Zealand, Sweden, and several Pacific island nations.
Population-weighted PM2.5 concentrations
Population-weighted annual average PM2.5 concentrations in 2016.
The global ozone map (see below) indicates that seasonal population-weighted average ambient ozone concentrations generally vary less geographically around the world compared with PM2.5. In 2016, ozone concentrations were relatively higher in the United States, West and Central sub-Saharan Africa, and throughout the Mediterranean, the Middle East, South Asia, and China. They remain high across both higher-income and lower/middle income regions of the world.
The global average remains below the most stringent global standard to protect human health, set at 70 parts per billion (ppb) in the United States, but the regional averages for South and East Asia exceed this level. You can explore patterns and trends in ozone levels using the interactive tools in Explore the Data.
Seasonal population-weighted ozone concentrations in 2016
Average seasonal population-weighted ozone concentrations in 2016.
In 2016, a total of 2.45 billion people — about one in three global citizens — were exposed to household air pollution. The global map of household air pollution exposures (see below) shows wide variations among countries in the proportion of their populations exposed. About two dozen countries in Africa have over 90% of their populations exposed to household air pollution. Although the proportions are smaller in India and China, their large populations mean that hundreds of millions of people in those countries are exposed to household air pollution — the most in the world. For more details, Read the Report.
Population exposed to household air pollution using solid fuels
Proportion of population exposed to household air pollution using solid fuels in 2016.
You can explore patterns and trends in exposures to fine particulate matter, ozone, and household air pollution using the interactive tools in Explore the Data. Compare results among individual countries and regional groupings. See the How To page for more detailed instructions.