Air Pollution: A Global Killer?

Air pollution is a major threat to global health, causing millions of premature deaths annually. In 2021, air pollution was attributed to 8.1 million deaths worldwide, making it the second leading risk factor for death, ahead of tobacco and poor diet. This includes the 700,000 deaths of children under five, with 500,000 of these linked to household air pollution due to cooking with polluting fuels. The death toll from air pollution varies across regions, with high-income countries like Finland, Norway, and Australia seeing less than 10% of pollution-related deaths, while in parts of Africa and Asia, this figure rises to over 40%.

In 2021, air pollution caused 8.1 million deaths globally

Air pollution is a leading cause of death globally, and in 2021, it caused 8.1 million deaths worldwide. This figure represents a significant global impact, with poor air quality becoming the second leading risk factor for death, ahead of tobacco and poor diet. The State of Global Air report, produced in collaboration with UNICEF, highlights the severity of the issue, as air pollution is linked to millions of healthy years of life lost globally.

The impact of air pollution is particularly devastating for children under five years old. In 2021, exposure to air pollution contributed to more than 700,000 deaths in this age group, making it the second-leading risk factor for death after malnutrition. Household air pollution due to the use of polluting fuels for cooking is a significant contributor, especially in Africa and Asia. UNICEF's report also emphasizes the health effects on young children, including premature birth, low birth weight, asthma, and lung diseases.

The primary driver of air pollution-related deaths is PM2.5 air pollution, which accounts for 7.8 million deaths. These fine particles, resulting from the burning of fossil fuels and biomass in various sectors, are less than 2.5 micrometers in diameter. They remain in the lungs, enter the bloodstream, and affect multiple organ systems. The health consequences include an increased risk of non-communicable diseases such as heart disease, stroke, diabetes, lung cancer, and chronic obstructive pulmonary disease (COPD).

Ozone (O3) is another critical air pollutant, contributing to an estimated 489,000 deaths globally in 2021. High levels of ozone are often found in areas with significant NO2 emissions, and the impact of ozone on childhood asthma development is a growing concern. Additionally, long-term exposure to air pollution has resulted in 8.7 million healthy years of life lost globally, further emphasizing the severe health implications.

The global impact of air pollution varies regionally, with high-income countries like Finland, Norway, Australia, and Canada experiencing lower attributed death rates. In contrast, regions such as East, West, Central, and Southern Africa, and South Asia, including Nigeria, Kenya, and Bangladesh, have higher rates of air pollution-related deaths. As the world grapples with the health and environmental consequences of air pollution, addressing this issue is crucial for improving global public health and mitigating climate change.

700,000 children under five died from air pollution

Air pollution is a leading cause of death globally, with 8.1 million deaths attributed to it in 2021. It is the second leading risk factor for death, ahead of tobacco and poor diet. Among children under five, air pollution is the second leading cause of death after malnutrition.

In 2021, exposure to air pollution was linked to more than 700,000 deaths of children under five years old. This accounted for approximately 15% of all global deaths in children under five. The death rate linked to air pollution in children under five has decreased by more than 50% since 2000, but it still takes a heavy toll. UNICEF Deputy Executive Director Kitty van der Heijden stated that "every day almost 2,000 children under five years die because of health impacts linked to air pollution." This figure includes deaths linked to indoor air pollution, which is particularly prevalent in Africa and Asia.

Indoor air pollution, caused by the use of polluting fuels for cooking and heating, is linked to more than half of all air pollution-related deaths in children under five. In 2021, 500,000 child deaths were linked to household air pollution, mostly in Africa and Asia. This is a result of families cooking indoors with polluting fuels, such as solid fuels and biomass. These activities contribute to air pollution and climate change, leading to respiratory illnesses and other health issues, particularly among children.

Outdoor air pollution is also a significant contributor to the death toll. Fine particulate matter (PM2.5), ozone (O3), and nitrogen dioxide (NO2) are all pollutants that have severe health impacts. PM2.5, which comes from the burning of fossil fuels and biomass in sectors such as transportation and industrial activities, is especially harmful. These tiny particles can remain in the lungs and enter the bloodstream, affecting multiple organ systems and increasing the risk of non-communicable diseases such as heart disease, stroke, diabetes, lung cancer, and chronic obstructive pulmonary disease (COPD).

The impact of air pollution on child health is inequitable, with the death rate in children under five in East, West, Central, and Southern Africa being 100 times higher than in high-income countries. UNICEF's Regional Director for East Asia and the Pacific, June Kunugi, stated that "every breath matters, but for too many children, every breath can bring harm." Urgent action is needed to address air pollution's impact on children, including strengthening climate and environmental policies, transitioning to clean energy, and enforcing air quality standards that protect children's health.

90% of deaths are attributed to PM2.5 air pollution

Air pollution is a leading cause of death globally, with 8.1 million deaths attributed to it in 2021. It has surpassed tobacco and poor diet as a risk factor for death, including for children under five years of age. Among these deaths, 7.8 million, or more than 90%, are linked to PM2.5 air pollution, including ambient PM2.5 and household air pollution.

PM2.5 refers to fine particulate matter that is less than 2.5 micrometers in diameter. These particles are so minuscule that they can remain in the lungs and even enter the bloodstream, causing inflammation and oxidative stress throughout the body. This, in turn, increases the risk of various noncommunicable diseases in adults, such as ischemic heart disease, lung cancer, chronic obstructive pulmonary disease (COPD), lower-respiratory infections, stroke, type 2 diabetes, and adverse birth outcomes.

The sources of PM2.5 air pollution are diverse and include the burning of fossil fuels and biomass in sectors such as transportation, residential homes, coal-burning power plants, industrial activities, and wildfires. The impact of PM2.5 pollution is particularly severe in Asia and Africa, with China and India accounting for 58% of the total global mortality burden. In 2019, long-term exposure to PM2.5 pollution contributed to approximately 4.14 million deaths worldwide, a significant increase from the previous decade.

Addressing PM2.5 air pollution is crucial for improving global public health and reducing the burden of disease, especially in highly affected regions. This involves implementing measures to reduce emissions, improve air quality, and protect vulnerable populations from the harmful effects of air pollution.

Overall, the high number of deaths attributed to PM2.5 air pollution underscores the urgent need for global efforts to mitigate this environmental and health crisis.

3.6 million premature deaths are caused by burning fossil fuels

Burning fossil fuels is a major contributor to air pollution, which has become the second leading risk factor for death worldwide. According to the latest State of Global Air report, air pollution accounted for 8.1 million deaths globally in 2021. While this figure includes deaths caused by both indoor and outdoor air pollution, it is clear that burning fossil fuels plays a significant role.

The death toll from burning fossil fuels in power generation, transportation, and industry is estimated to be 3.6 million premature deaths annually. This means that phasing out fossil fuels and transitioning to clean energy sources could prevent an excess mortality rate of 3.6 million people each year. This number is more than six times the annual death toll from murders, war deaths, and terrorist attacks combined.

The impact of burning fossil fuels is particularly devastating in certain regions. China and India bear the brunt of premature deaths caused by air pollution, with nearly five million deaths in those two countries alone. Other severely affected areas include Western Europe, Southeast Asia, and parts of the United States, such as the Northeast and Midwest.

The tiny particles released by burning fossil fuels, known as PM2.5, have severe health consequences. These particles, measuring less than 2.5 micrometers in diameter, can remain in the lungs and enter the bloodstream, increasing the risk of various non-communicable diseases. These include heart disease, stroke, diabetes, lung cancer, and chronic obstructive pulmonary disease (COPD).

Addressing air pollution caused by burning fossil fuels is crucial for protecting the health of children. In 2021, exposure to air pollution was linked to more than 700,000 deaths of children under five years old, making it the second-leading risk factor for death in this age group, after malnutrition. The developing fetus and young children are more susceptible to the adverse effects of air pollutants due to their rapid growth and developing brains and physiological systems.

Air pollution is the second leading risk factor for death

Air pollution is a major global concern, and it is now the second leading risk factor for death worldwide. In 2021, air pollution was responsible for 8.1 million deaths globally, according to the State of Global Air (SoGA) report. This report, released by the Health Effects Institute (HEI), an independent U.S.-based non-profit research organization, highlights the severe health impacts of air pollution. The effects of air pollution are far-reaching, contributing to millions of healthy years of life lost worldwide and causing debilitating chronic diseases that put tremendous strains on healthcare systems, economies, and societies.

Outdoor air pollution, particularly in cities, is a significant contributor to the problem. Fine particulate matter, or PM2.5, from the burning of fossil fuels and biomass in transportation, power generation, residential homes, industrial activities, and wildfires, poses a serious health risk. These tiny particles can enter the lungs and bloodstream, increasing the risk of non-communicable diseases such as heart disease, stroke, diabetes, lung cancer, and chronic obstructive pulmonary disease (COPD). High levels of nitrogen dioxide (NO2) in the air, often found in areas with high NO2 emissions, can also lead to higher ozone levels, exacerbating the health impacts of air pollution.

Indoor air pollution is also a critical factor in the overall death toll attributed to air pollution. Around 2.4 billion people are exposed to dangerous levels of indoor air pollution, primarily from using polluting open fires or simple stoves for cooking with fuels like kerosene, biomass, and coal. This type of household air pollution disproportionately affects low- and middle-income countries, with nearly 500,000 child deaths linked to it, mostly in Africa and Asia.

Children under five years old are especially vulnerable to the health effects of air pollution, with increased risks of premature birth, low birth weight, asthma, and lung diseases. In 2021, exposure to air pollution was linked to more than 700,000 deaths in this age group, making it the second-leading risk factor for death globally for children under five, after malnutrition.

Addressing air pollution is crucial to reducing its impact on global health and mitigating climate change. Phasing out fossil fuels and adopting clean energy sources can significantly reduce the death toll attributed to air pollution. Additionally, implementing policies to reduce air pollution can provide a "win-win" strategy for both climate and health outcomes, lowering the burden of disease and contributing to near- and long-term climate change mitigation.

Frequently asked questions