PICS: 7 million died of air pollution in 2012

According to the UN health agency, WHO, the air pollution ranges from cooking fires to auto fumes. "Air pollution, and we're talking about both indoors and outdoors, is now the biggest environmental health problem, and it's affecting everyone, both developed and developing countries," says Maria Neira, the World Health Organisation's public and environmental health chief. Globally, pollution was linked to one death in eight in 2012, new WHO research found. The biggest pollution-related killers were heart disease, stroke, pulmonary disease and lung cancer.