Last week, Beijing has been hit by a cloud of fine dusts, particularly Pm2.5 and Pm10, which reduced visibility and led Chinese authorities to ask those who are more at risk, such as children and elderly people, to do not spend much time outdoor, in order to avoid breathing in particles causing lung disorders. On this occasion, the British weekly newspaper The Economist republished the graph of the most polluted cities in world's biggest economies
, realised according to the World Health Organisation’s data. Alarming figures are several. For example, Beijing is not the Chinese most polluted metropolis, but Lanzhou, prefecture-level city in the northwest of the country. Ludhiana, India, is the most hazardous city for people’s health. Negative figures also come from our country, Italy, since Turin is the first European city in the list, followed by Seville, Zaragoza, and Paris.