India Gate can barely be seen through smog in Delhi. Around 4.3 million deaths in 2012 were caused by indoor air pollution, mostly from wood and coal stoves in Asia. Photograph: Louis Dowse/Corbis
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 came as a result of stroke and heart disease, 11% from lung diseases and 6% from cancers. The vast majority were in Asia, with 180,000 in the Americas and Europe combined, said the WHO.
Indoor air pollution led to 4.3 million deaths, of which 34% were caused by strokes, 26% heart diseases and 12% respiratory disease in children. Only 19,000 of these deaths were in rich countries, with the vast majority being in low- and middle-income countries. Because many people are exposed to both indoor and outdoor air pollution, the WHO said deaths attributed to the two sources cannot be added together.
“The risks from air pollution are now far greater than previously thought or understood, particularly for heart disease and strokes,” said Maria Neira, director of WHO’s department for public health, environmental and social determinants of health. “Few risks have a greater impact on global health today than air pollution; the evidence signals the need for concerted action to clean up the air we all breathe.”