Guardian: Air pollution has become the world's single biggest environmental health risk, linked to around 7 million or nearly one in eight deaths in 2012 according to the World Health Organisation (WHO).
The new figures are more than double previous estimates and suggest that outdoor pollution from traffic fumes and coal-burning, and indoor pollution from wood and coal stoves, kills more people than smoking, road deaths and diabetes combined.
Around 80% of the 3.7 million deaths from outdoor pollution...