Residents of Paris, London, Los Angeles and Hong Kong are breathing cleaner air than a year ago, while N’Djamena, Baghdad and New Delhi are suffering higher levels of pollution, the latest report on global air quality shows.
Roughly 90 per cent of the world’s population is still breathing air that poses a risk to health but the gap between high and low income cities is widening, the annual study by IQAir, the Swiss-based air technology group found, using 30,000 ground level sensors from more than 7,000 cities.
The study measured the concentration of fine particulate matter with diameters of up to 2.5 microns, known as PM2.5, one of the most hazardous pollutants as it may be able to enter the bloodstream.
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