Twice as bad: new estimates for mortality from air pollution. Lancet Respiratory Medicine, April 2014.
Talha Khan Burki
WHO have upwardly revised their figures for the global mortality caused by air pollution. They estimate that about 7 million deaths occurred as a result of indoor and outdoor air pollution in 2012. The new figures take into account improvements in the methods and data collection used in previous years and honed techniques for measuring exposure-response.Indoor air pollution accounted for 4·3 million deaths in 2012, largely in the South-East Asia and Western Pacific regions. Respiratory illness made up 40% of the death toll. It all comes down to smoke inhalation, either from open fires or inefficient cook stoves. Children younger than 5 years are particularly vulnerable: 2012 saw over 500 000 deaths from acute lower respiratory infections related to indoor air pollution in this age bracket.
Outdoor air pollution accounted for 3·7 million deaths in 2012, concentrated in low-income and middle-income countries; 389 000 of these deaths were from chronic obstructive respiratory disease, and 227 000 from lung cancer (emissions from diesel engines are particularly culpable in this). Since communities are exposed to several types of pollution, WHO estimated the total number of pollution-related deaths at 7 million (rather than 8 million).Tackling outdoor pollution requires a wide ranging approach. “We would like to have more interventions on healthy urban planning”, affirmed WHO’s Maria Neira. She notes that the transport sector has provided much evidence on environmentally friendly and sustainable systems. Clearly, industry has a large part to play, and there are plenty of proven interventions, such as fitting flue-gas desulphurisation systems to coal-burning power plants, that can help ameliorate matters.
Later this year, WHO will launch its guidelines on indoor air quality. About 3 billion people live in households that rely on solid fuel for cooking and heating. “They burn what is available”, explains Jon Ayres from Birmingham University. Rolling out an efficient means of combusting this fuel, as envisaged by the UN Foundation’s Global Alliance for Clean Cook Stoves, is crucial. But simply ensuring a supply of such stoves will not suffice—when they break down, users tend to return to their previous habits. Ayres emphasises the importance of co-opting local entrepreneurs to produce inexpensive, good-quality stoves and subsequently provide maintenance services. “It’s a big job—we have to enable great swathes of people to become the users, producers, and maintainers of these better stoves”, he told The Lancet Respiratory Medicine.
