Pollution in cities around the world has been increasing since the last global study on the issue was published two years ago, the World Health Organisation (WHO) warned on Wednesday (May 11), estimating pollution was responsible for 7 million premature deaths annually.
WHO's Director for Public Health, Environmental and Social Determinants of Health Maria Neira said during a news briefing in Geneva that "This is obviously a major, major public health problem. And that is why we need to raise awareness; we need to increase the measures that are taken, and the countries need to move on monitoring air quality, but monitoring air quality for essentially taking action, and therefore reducing the very negative impact on the health of the people."
From a positive point of view, however, Neira insisted that more and more cities were reporting on air pollution and collecting data.
In 2014, when WHO published its last study, its database consisted of 1,600 cities. It now comprises 3,000 cities from 103 countries.
For this study, the World Health Organisation compared the levels of small and fine particles in 795 cities from 67 countries. The most polluted cities are still in India and in China, as WHO's previous study had found.
Neira added that the WHO didn't want to name the dirtiest cities, since many cities, probably the most polluted ones, were still being left out of the study, because they were not collecting data.