Air pollution kills – Evidence from a global analysis of exposure and poverty

Globally, poor air quality is estimated to cause some 7 million deaths each year, as it05.18_air_pollution_kills_blog_image increases the risk of a wide range of cardiovascular and respiratory diseases. Yet the exposure to and impact of air pollution are not equally distributed. Air pollution is particularly prevalent in industrializing developing economies. Less stringent air quality regulations, the prevalence of older polluting machinery and vehicles, subsidized fossil fuels, congested urban transport systems, rapidly developing industrial sectors, and cut-and-burn practices in agriculture are all contributing to heightened pollution levels. The lack of affordable quality healthcare services further increases air pollution related mortality.

And within countries, poorer and marginalized communities are often more exposed. Low-paying jobs are more likely to require physical outdoor labor, leading to heightened exposure. Pollution sources, such as industrial plants or transport corridors, are disproportionately located in low-income neighborhoods. And as air pollution increases, housing prices go down, which in turn reinforces the low-income status of neighborhoods. In short, as health, well-being, and productivity suffer, air pollution can reinforce socio-economic inequalities .

Figure 1. Average annual PM2.5 concentrations in Southeast Asia 

Chart 1

Source: Rentschler & Leonova (2022) based on van Donkelaar et al (2021)

Poor people’s exposure to harmful air pollution.

While many studies have focused on air pollution in rich countries, a better understanding of the interplay between air pollution and poverty is crucial for several reasons. Studies from high-income countries on the health risks associated with air pollution may not be directly transferable to low-income communities, where the nature of occupations and healthcare differ substantially . The health and productivity implications of air pollution will impact the socio-economic prospects of developing countries. This is especially significant in low-income countries, which tend to still have relatively low anthropogenic air pollution levels compared to more industrialized middle-income countries. Here, there is still an opportunity to ensure that development progress does not come hand in hand with intensifying air pollution and the associated detrimental effects on health and well-being .

2.8 billion people face hazardous air pollution levels

In a new study, we provide a comprehensive account of the relationship between ambient (outdoor) air pollution exposure, economic development, and poverty in 211 countries and territories. It presents global exposure estimates for the World Health Organization’s 2021 revised fine particulate matter (PM2.5) thresholds. In addition, we provide estimates of the number of poor people exposed to unsafe PM2.5 concentrations. The findings are based on high-resolution air pollution and population maps with global coverage, as well as subnational poverty estimates based on harmonized household surveys.

Our estimates show that globally 7.3 billion people, or 94 percent of the world population, face air pollution levels considered unsafe by the WHO (annual average PM2.5 concentration over 5 μg/m3). For 2.8 billion people pollution levels are hazardous – with PM2.5 concentrations over 35 μg/m3, which implies a mortality rate that is more than 24 percent higher than in safe areas.

Figure 2. Share of population exposed to PM2.5 concentrations over 15 μg/m3

Figure 2

One in ten people exposed to unsafe air pollution live in extreme poverty

We estimate that 716 million people living in extreme poverty, calculated as living on less than $1.90 per day, are directly exposed to unsafe PM2.5 concentrations; of these, 405 million, or 57 percent are in Sub-Saharan Africa. Further, 275 million people living in extreme poverty are exposed to hazardous PM2.5 concentrations (over 35 μg/m3). Approximately one in ten people exposed to unsafe levels of air pollution live in extreme poverty –making them particularly vulnerable to prolonged adverse impacts on their livelihoods and well-being. For the extreme poor, the same air pollution level likely means increased severe health risks compared to higher income households, as the effects of air pollution are compounded by other poverty risk factors in addition to inequitable access to affordable healthcare.

Pollution is highest in middle-income countries

Yet, the estimates also show that the vast majority of people breathing unsafe air are located in middle-income countries, where 5.5 billion people are exposed to hazardous PM2.5 levels (over 35 μg/m3) – compared to just 40.5 million in low- and high-income countries combined. As a share of the overall population, PM2.5 exposure is also by far the highest in middle-income countries. About 64.5 percent of people in lower-middle-income countries are exposed to PM2.5 levels over 35 μg/m3, compared to just 4.4 percent in low-income countries and 0.9 percent in high-income countries .

global exposure

Towards healthier lives and better livelihoods

Our study affirms the case for targeted measures that reduce the pollution intensity of economic growth – for instance, supporting the uptake of clean technologies and fuels. In addition, measures are needed to directly address the disproportionate exposure of poor people to pollution. For example, improving the provision of affordable and adequate healthcare in large urban centers can help reduce mortality. Mandating transparent accounting for environmental and health externalities in planning decisions can help to steer pollution sources, like industrial zones, away from low-income communities. Finally, removing incentives that perpetuate the over-consumption of polluting fuels can yield a double dividend for poor people. For instance, fossil fuel subsidies are well documented to benefit richer households disproportionately, but the air pollution externalities associated with subsidized fossil fuel consumption are also a burden that can be borne disproportionately by poorer households.

The Earth’s atmosphere and oceans are both common resources that are entirely dependent on international cooperation if they are to be managed sustainably. Doing so calls for renewed commitment at the broadest level. Last November, at the 26th Conference of the Parties of the U.N. Framework Convention on Climate Change in Glasgow, 15 countries pledged to increase protection of their maritime areas, known as national exclusive economic zones (EEZs), by investing in ocean-based renewable energy and decarbonizing their shipping industries. Yet these pledges to address climate change in aggregate fall far short of the global ambition needed to avoid the worst and cumulative impacts of climate change on oceans. 

The latest report of the Intergovernmental Panel on Climate Change is a stark reminder of the narrowing window to bolster global climate action on oceans. A series of global events in 2022 has aimed to drive momentum — including  the One Ocean Summit in France in February, Our Ocean Conference in Palau in April, and the Stockholm+50 Conference in Sweden and UN Ocean Conference in Lisbon in June.  Pressure continues to increase from all quarters to maintain support for ongoing global initiatives, from the UN Environment Assembly negotiations on marine plastics to UN negotiations on biodiversity in areas beyond national jurisdiction. 

The World Bank is supporting countries to chart a new course away from business as usual and towards a Blue Economy—defined as the sustainable and integrated development of oceanic sectors in healthy oceans.  Such a path necessarily involves greater collaboration as ocean-based resources are often either shared or migratory, rendering international cooperation essential to the sustainable management of ocean resources in the face of growing climate impacts on oceans.

“The World Bank is supporting countries to chart a new course away from business as usual and towards a Blue Economy—defined as the sustainable and integrated development of oceanic sectors in healthy oceans.”

Ocean governance considerations were central to the African Union’s continent-wide Blue Economy Strategy released in 2019, which aims to chart a coordinated path to address regional threats, including sea piracy, illegal fishing, climate change, and pollution. The strategy also seeks to harness the potential for oceans to provide jobs, strengthen food security and environmental sustainability. It focuses on five thematic areas: (i) fisheries, aquaculture, and conservation, (ii) shipping and transport, (iii) environmental sustainability, climate change, and coastal tourism and infrastructure, (iv) sustainable energy, mineral resources, and innovative industries, and (v) governance, policies, and job creation. 

Such strategies and the activities they envision are anchored in international and regional conventions relating to the Blue Economy, including the U.N. Convention on the Law of the Sea, the Abidjan, Nairobi and Jeddah regional seas conventions, the MAPROL Convention on marine pollution, the Convention on Biological Diversity, and the U.N. Framework Convention on Climate Change and the Paris Agreement. 

To build on these cornerstones of the global ocean regime, the Environment and International Law Practice Group of the World Bank has launched an Ocean Governance Capacity Building Program to support the development and implementation of ocean governance strategies. The training program was developed in partnership with the University of Melbourne Law School, the Division for Ocean Affairs and the Law of the Sea of the Office of Legal Affairs of the United Nations, the Food and Agricultural Organization of the United Nations, the International Seabed Authority, and the Maritime and Oceanic Law Centre at the University of Nantes in France. It brings together experts from the partner organizations, government officials and other stakeholders for training workshops on ocean governance focusing on the key international legal frameworks. 

Following two successful workshops focused on the Pacific and Africa Regions in 2021, which trained more than 150 stakeholders, the World Bank will launch a self-paced e-learning course in the summer 2022 and plan future workshops in the Indian Ocean, Latin America, and other regions. This training program is one of several supported by the multi-donor trust fund PROBLUE, established in 2018 with support from 15 development partners in 11 countries and the European Union. PROBLUE support will continue for future efforts to bring together key stakeholders and build more robust global ocean governance.