7 in 10 cities suffer from ‘dangerous’ air pollution – WHO

Almost 90% of the world’s urban population live in cities where the air is unsafe to breathe, according to UN data

Pic: Thanh Mai Bui Duy/Flickr

Pic: Thanh Mai Bui Duy/Flickr

By Sophie Yeo

Dangerous air pollution afflicts 7 out of 10 of the world’s cities, according to data released today by the UN.

Of the 1,600 cities around the globe monitored by the World Health Organisation (WHO), air quality was only considered ‘safe’ in 30%.

As larger, more populous cities have worse air quality, this means only 12% of the world’s urban population are breathing safe air, putting almost 90% of the urban world at risk of respiratory and heart problems, strokes and other diseases

Around half of the urban population being monitored are exposed to levels of air pollution at least 2.5 times higher than that deemed ‘safe’ by the WHO, according to the data.

“Too many urban centres today are so enveloped in dirty air that their skylines are invisible,” said Dr Flavia Bustreo, WHO Assistant Director-General for Family, Children and Women’s Health.

“Not surprisingly, this air is dangerous to breathe. So a growing number of cities and communities worldwide are striving to better meet the needs of their residents – in particular children and the elderly.”


Limitations in air pollution data collection in places such as Africa and the Eastern Mediterranean means that some of the worst polluted cities are not included in today’s statistics. The reality is likely to be worse than what appears on paper, says Sophie Bonjour from WHO, who helped to compile the database.

In high income countries, 816 cities reported on PM2.5 levels, while in low- and middle-income countries, only 70 cities registered this information. PM2.5 are the fine particles that are most hazardous to human health.

“A lot of cities that are not represented have a worse air quality,” Bonjour told RTCC. “We have to bear in mind we have much more data on cities from high income countries, of course, so a lot of cities we don’t have. If we had the data, I guess this number would be much lower than 30%.”

And in most cities air pollution is getting worse, the data shows, despite some efforts to combat the problem. They attribute this to continued reliance on fossil fuels, as well as transport, inefficient buildings, and the use of biomass for cooking and heating.

Bejing, for instance, regularly registers levels of air pollution considered ‘hazardous’ to human health, while a haze which descended on Paris in March caused the government to impose a partial transport ban.

Last month, the WHO said that air pollution was now the world’s biggest environmental threat, as it killed some seven million people in 2012.

Clean cities

In response to the data, the WHO points out that action to tackle air quality not only improves the lives of those in the cities, but can also contribute to economic development.

Measures such as effective public transport ad cycle-friendly streets can serve as a catalyst for local economic development. Some major cities in Latin America prove this point, says the WHO, where air quality has reached ‘safe’ levels.

“Effective policies and strategies are well understood, but they need to be implemented at sufficient scale,” said Dr Maria Neira, WHO Director for Public Health, Environmental and Social Determinants of Health.

“Cities such as Copenhagen and Bogotà, for example, have improved air quality by promoting ‘active transport’ and prioritizing dedicated networks of urban public transport, walking and cycling.”

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