Seven Million Deaths in 2012 From Air Pollution

Health Letter, September 2014

By Jennifer Rubio

When you think of air pollution, you may think only of the impending threat of global warming due to the greenhouse effect. But air pollution also has more immediate consequences. The World Health Organization (WHO), in a report released in late March, estimated that 7 million people died in 2012 from air pollution — nearly one in eight deaths worldwide. This sobering finding places air pollution as the number one environmental threat to health and highlights the importance of air pollution regulations to protect public health.

Two major types of pollution accounted for the 7 million deaths: household air pollution, which comes from solid fuels used for cooking and heating, and ambient air pollution, the pollution in outdoor environments. Both types are problematic. While 3.7 million deaths were attributable to ambient air pollution, 4.3 million were caused by household air pollution. (There is some overlap between ambient and household pollution exposure, so the figures do not add up to 7 million.)

Low- and middle-income countries in the Western Pacific and Southeast Asia had the highest number of deaths, with 3.3 million deaths related to indoor air pollution and 2.6 million related to outdoor air pollution.[1] Deaths were primarily from cardiovascular events, including ischemic heart disease and stroke.

Urban areas in most of the countries along the southern coast of Asia — including Iran, Pakistan, India, Bangladesh and China — have some of the heaviest air pollution in the world. Pollution levels in those areas range from three times (China) to more than ten times (Pakistan) those in most Western European countries.[2] (See the WHO country-by-country air pollution map here.) Not surprisingly, the WHO report found links between air quality and public health, as, in most cases, the higher-pollution areas were those with higher mortality rates.

Indoor pollution: A major threat

Over 3 billion people worldwide heat their homes and cook with solid fuel, such as wood, coal, dung, crop waste and charcoal. The inefficient combustion of these solid fuels on open fires or leaky stoves causes the emission of small particles, including soot, into the air. Indoor pollution is further exacerbated by poor ventilation, which allows the soot to accumulate to as much as 100 times the acceptable levels. “Having an open fire in your kitchen is like burning 400 cigarettes an hour,” said Dr. Kirk Smith, professor of global environmental health at the University of California, Berkeley, in an article for the WHO.[3] Like cigarette smoke, soot particles from burning solid fuels, when inhaled, can penetrate deep into lung tissue and cause respiratory diseases such as pneumonia as well as cardiovascular diseases.[4]

Women and children spend more time in the home and close to the hearth or stove, making them particularly susceptible to diseases related to indoor air pollution. For example, more than half of fatal cases of pneumonia in children under 5 are due to household air pollution.[5] Also, women exposed to indoor smoke are more likely to develop chronic obstructive pulmonary disease (COPD) and lung cancer.[6]

As with air pollution in general, exposure to household air pollution is more prevalent in low- to middle-income countries, primarily in Africa, Southeast Asia and the Western Pacific.

Ambient air pollution: A clear danger to public health

Ambient air pollution caused 3.7 million deaths worldwide in 2012, in both cities and rural areas.[7] The great majority of the deaths attributable to outdoor air pollution in 2012 were from cardiovascular causes: 40 percent from ischemic heart disease, such as heart attacks, and another 40 percent from stroke.[8] The remaining deaths were caused by COPD and lung cancer in adults and pneumonia in children.[9]

As with household air pollution, small particles in the atmosphere are a major component of outdoor air pollution and a leading cause of both cardiovascular and respiratory diseases. The major sources of these particles are diesel-fueled vehicles and coal-fired power plants.[10]

Exposure to ambient air pollution varies by region. The WHO points out that risk is high in developing countries, where urbanization is occurring but mitigating measures, such as regulations, are not robust.

For example, a World Bank study released at the same time as the March WHO report analyzed China’s problem of wasteful urban sprawl.[11] The researchers called on the country to build more efficient, better-planned cities — a recommendation that the WHO echoed. “Building cities around rapid public transport systems, complemented by dedicated walking and cycling networks, is more fuel efficient,” the WHO’s report said. It also suggested “more compact cities, more energy efficient housing, fewer private car trips, and thus fewer air pollution emissions overall.”[12]

Up to policymakers to implement solutions

Improving air quality worldwide, according to the WHO, would avert 12.7 percent of deaths.[13] It would also mitigate the effects of climate change, including extreme weather events and the spread of diseases from contaminated water and food, as well as insect-transmitted disease like malaria.[14]

The WHO has released new guidelines for air quality in households and is working with countries to monitor and address the health dangers of household air pollution. However, the WHO admits in its report, “There is a gap in our understanding of the most effective interventions at protecting health and data collection on the issue at both a national and global level.”[15] Organizations such as the Global Alliance for Clean Cookstoves are also working to provide households in developing countries with cleaner-burning stoves.[16]

No such gap in understanding exists when it comes to preventing further deaths from ambient air pollution. Though the policies that would reduce this type of pollution are well known, they are not being implemented worldwide.

“Excessive air pollution is often a by-product of unsustainable policies in sectors such as transport, energy, waste management and industry. In most cases, healthier strategies will also be more economical in the long term due to health-care cost savings as well as climate gains,” says Dr. Carlos Dora, the WHO coordinator for public health, environmental and social determinants of health.[17]

But these solutions, the WHO notes, are “largely beyond the control of individuals and [require] action by public authorities at the national, regional and even international levels.”[18]

The WHO cites both lack of awareness and “under-appreciation of the potential solutions” as barriers to improving ambient air quality.[19] The latter is especially troubling, as it implies that despite knowledge of the problem and of potential solutions, policymakers lack the political will to implement measures that would improve public health.

Yet the burden falls squarely on the shoulders of policymakers and regulatory bodies: It is up to governments to implement the WHO’s suggested solutions, including encouraging power plants to use more clean and renewable fuels, investing in energy efficiency and raising awareness of the cost — in both money and lives — of air pollution.[20]


References

[1] World Health Organization. 7 million premature deaths annually linked to air pollution. http://www.who.int/mediacentre/news/releases/2014/air-pollution/en/. Accessed August 1, 2014.

[2] World Health Organization. Public Health and Environment (PHE): outdoor air pollution. Exposure to particulate matter less than 10 µm in diameter in urban areas, 2003-2010. http://gamapserver.who.int/gho/interactive_charts/phe/oap_exposure/atlas.html. Accessed August 1, 2014.

[3] World Health Organization. Clean household energy can save people’s lives. March 2014. http://www.who.int/features/2014/clean-household-energy/en/. Accessed August 1, 2014.

[4] World Health Organization. Household air pollution and health. March 2014. http://www.who.int/mediacentre/factsheets/fs292/en/. Accessed August 1, 2014.

[5] Ibid.

[6] Ibid.

[7] World Health Organization. Ambient (outdoor) air quality and health. March 2014. http://www.who.int/mediacentre/factsheets/fs313/en/. Accessed August 1, 2014.

[8] World Health Organization. 7 million premature deaths annually linked to air pollution. http://www.who.int/mediacentre/news/releases/2014/air-pollution/en/. Accessed August 1, 2014.

[9] Ibid.

[10] World Health Organization. Frequently Asked Questions. Ambient and Household Air Pollution and Health. 2014. http://www.who.int/phe/health_topics/outdoorair/databases/faqs_air_pollution.pdf. Accessed August 1, 2014.

[11] Jacobs A, Johnson I. Pollution Killed 7 Million People Worldwide in 2012, Report Finds. The New York Times. March 25, 2014. http://www.nytimes.com/2014/03/26/world/pollution-killed-7-million-people-worldwide-in-2012-report-finds.html?_r=0. Accessed August 1, 2014.

[12] World Health Organization. Frequently Asked Questions. Ambient and Household Air Pollution and Health. 2014. http://www.who.int/phe/health_topics/outdoorair/databases/faqs_air_pollution.pdf. Accessed August 1, 2014.

[13] World Health Organization. Frequently Asked Questions. Ambient and Household Air Pollution and Health. 2014. http://www.who.int/phe/health_topics/outdoorair/databases/faqs_air_pollution.pdf. Accessed August 1, 2014.

[14] Ibid.

[15] World Health Organization. Frequently Asked Questions. Ambient and Household Air Pollution and Health. 2014. http://www.who.int/phe/health_topics/outdoorair/databases/faqs_air_pollution.pdf. Accessed August 1, 2014.

[16] Global Alliance for Clean Cookstoves website. http://www.cleancookstoves.org/. Accessed August 1, 2014.

[17] World Health Organization. 7 million premature deaths annually linked to air pollution. http://www.who.int/mediacentre/news/releases/2014/air-pollution/en/. Accessed August 1, 2014.

[18] World Health Organization. Frequently Asked Questions. Ambient and Household Air Pollution and Health. 2014. http://www.who.int/phe/health_topics/outdoorair/databases/faqs_air_pollution.pdf. Accessed August 1, 2014.

[19] World Health Organization. Frequently Asked Questions. Ambient and Household Air Pollution and Health. 2014. http://www.who.int/phe/health_topics/outdoorair/databases/faqs_air_pollution.pdf. Accessed August 1, 2014.

[20] World Health Organization. Frequently Asked Questions. Ambient and Household Air Pollution and Health. 2014. http://www.who.int/phe/health_topics/outdoorair/databases/faqs_air_pollution.pdf. Accessed August 1, 2014.