Air pollution is a major issue for cities around the world, with regular dangerously high pollution levels in China coupled with recent warnings in Paris and London. While China’s air pollution alone led to 1.2 million premature deaths in 2010, the World Health Organisation (WHO) is revealing today that 7 million people died from polluted air worldwide in 2012. The latest findings are more than double previous estimates, meaning one in eight deaths worldwide are caused by air pollution.

Of the 7 million deaths, the WHO report notes that more than half (4.3 million) were caused by indoor air pollution, largely due to households using wood, coal, or biomass stoves. While the effects of air pollution aren’t obvious immediately, it’s a silent killer that scientists believe could contribute to heart disease and strokes. The report also notes that women and children are at higher risk of exposure to indoor pollution in developing countries, mainly due to the amount of time spent at home breathing in smoke and soot from nearby stoves.

"The risks from air pollution are now far greater than previously thought or understood."

"The risks from air pollution are now far greater than previously thought or understood, particularly for heart disease and strokes," says Dr. Maria Neira, a director at WHO. "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."