Milan mayor casts doubt on city's ranking as third most polluted in world

IQAir labelled Milan 'unhealthy' over PM 2.5 levels, triggering limits on daytime traffic Milan was under a blanket of smog on Tuesday as a row broke out over data from a monitoring group that ranked the northern Italian city long known for its poor air quality among the most polluted in the world, alongside Dhaka, Lahore and Chengdu. The controversy began on Sunday, when the Swiss real time air quality website IQAir labelled Milan "unhealthy" as the level of fine particulate matter, or PM 2.5, ...