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Indoor air pollution kills a staggering 4.3 million people a year in the developing world


The surprising problem that is the greatest environmental danger to women and children

By Bjorn Lomborg on April 27, 2015

The world’s greatest environmental threat disproportionately harms women and children, particularly in the developing world: it is indoor air pollution.

The World Health Organization estimates that indoor pollution kills 4.3 million people a year, mainly because 2.8 billion people still use firewood, dung and coal for cooking and keeping warm, breathing polluted air inside their homes every day. Indoor air pollution from cooking and heating with open fires can cause harm equivalent to smoking two packs of cigarettes a day.

And, because of their greater involvement in daily kitchen activities in societies where indoor cooking is prevalent, women experience higher personal exposure levels than men. During long hours spent indoors at their mothers’ sides, young children, too, are breathing more life-threatening pollutants than adult males.

It is well known that air pollution in cities like Beijing or Bangkok is far worse than in developed-world cities like New York. On average, developing world cities are 10 times more polluted. But what most don’t realize is that the indoor air in the homes of almost half this world’s families is 10 times worse than the outdoor air in Bangkok. For most women and children, the polluted public spaces of emerging mega-cities are dramatically cleaner, in terms of air quality, than their own smoke-filled homes.

To put the issue in perspective, take the much more talked-about environmental problem of global warming. WHO estimates that currently 141,000 a year die from global warming, while 4.3 million die right now each year from indoor air pollution—a figure many  times higher than even the 250,000 annual deaths from global warming WHO anticipates by 2050. Of course, this does not mean global warming is an unimportant environmental issue, but clearly indoor air pollution should be given high priority as an urgent concern of humanitarians.

The good news is that it is comparatively cheap to tackle the issue. One effective step is to provide half of these 2.8 billion people with improved cooking stoves, which dispel smoke to the outside through chimneys and vents. That alone would save almost half a million lives each year, and avoid 2.5 billion disease days. The cost would be around $5 billion a year, but this investment would yield economic, social and environmental benefits amounting to $52 billion a year.

Right now, we are presented with an important window of opportunity to influence environmental priorities as the world’s 193 governments are gearing up to select a set of development and environmental targets for the next 15 years through the United Nations. These new targets are set to replace the very successful Millennium Development Goals (MDGs) that expire this year.

My think tank, the Copenhagen Consensus, has asked 60 teams of top economists, including several Nobel laureates, to evaluate the economic, social and environmental costs and benefits of some of these proposals, to guide policy makers in the direction of the targets expected to do the most good.

The experts have not only looked into air pollution, they have addressed a wide range of the top environmental challenges for the next 15 years. Several of these are particularly consequential for women.

Take access to water and sanitation: Even though we have seen improvement, 750 million people have no access to any safe source of drinking water, and 2.5 billion – almost half of the developing world – lack even a basic latrine. Beyond the economic impact on families, the inconvenience and demoralizing drudgery it leads to, this deficit actually kills 360,000 people each year.

And, again, women are harder hit than men: The shortage of sanitation and places to wash in the slums exacerbates their insecurity. Apart from the disease that spreads from unclean water and lack of sanitation, not having access to facilities means long walks to community toilets which, especially at night, vastly increases the risk of rape and other gender-based violence. Amnesty International did one study aptly titled “Risking Rape to Reach a Toilet.

Most slum residents use shared pit latrines, with as many as 50 to 150 people sharing one location. It can take 10 minutes to walk from the user’s home to the toilet. To avoid the perilous journey, some women are forced to resort to “flying toilets”–disposing of human waste by throwing it into the open in a plastic bag.

Moreover, most water is fetched by women: More accessible sources could save them 40 minutes per day. Getting water and sanitation for everyone by 2030 means installing more wells, boreholes and springs to serve 3 billion people with basic sanitation. This will not be cheap. It is likely to cost $45 billion annually, but the results would be massive: 170,000 fewer deaths from contaminated water and 80,000 fewer deaths from improper sanitation.

Similarly, research suggests that women are more likely to die in climate disasters, because they often haven’t learned to swim, they have restricted mobility because of their clothing and, in some cultures, women leave their homes and evacuate a threatened area too late because they wait for a male relative to accompany them. In total, about 10,000 women a year die from weather related disasters compared to 4,500 men.

The world’s most pressing environmental issues are entwined with human rights challenges. When world leaders meet at the UN in New York in September to agree on the final set of global targets for the next 15 years, we should demand that they focus on the smartest solutions to the environmental ills that do the most harm.

Dr. Lomborg researches the smartest ways to improve the environment and the world. He is one of TIME Magazine’s 100 most influential people in the world, one of the 75 most influential people of the 21st century according to Esquire magazine, and one of the 50 people who could save the planet according to the UK Guardian. Lomborg has repeatedly been named one of Foreign Policy’s Top 100 Global Thinkers. With his think tank, the Copenhagen Consensus, he works with 100+ of the world’s top economists and 7 Nobel Laureates to identify the most effective solutions across development and environment. His latest book is Prioritizing The World.