Air Pollution: Global Survey Insights

Air pollution is a serious global issue that poses a major threat to human health. It is caused by a range of sources, including household combustion devices, motor vehicles, industrial facilities, and natural phenomena such as wildfires and volcanic activity. According to the World Health Organization (WHO), almost all of the global population (99%) is exposed to air pollution levels that exceed recommended guidelines, with low- and middle-income countries suffering the highest exposures. The combined effects of ambient and household air pollution are associated with 6.7 million premature deaths annually, making it one of the leading risk factors for death and a significant contributor to the global disease burden. WHO plays a crucial role in monitoring and addressing air pollution, providing technical support to member states, and offering guidance and strategies to mitigate the risks associated with air pollution.

Air pollution is a leading cause of death and disease

Air pollution is a combination of outdoor and indoor particulate matter and ozone. It is a major threat to health across the globe and is linked to respiratory and other diseases. According to the World Health Organization (WHO), almost all of the global population (99%) breathe air that exceeds WHO guideline limits and contains high levels of pollutants. This includes particulate matter, carbon monoxide, ozone, nitrogen dioxide, and sulfur dioxide.

The sources of air pollution vary by location, but common sources include household combustion devices, motor vehicles, industrial facilities, and forest fires. In recent years, agricultural land use has also been on the rise, contributing to increased air pollution. The impact of natural sources, such as volcanic activity, wildfires, and dust or sandstorms, varies depending on the local environment.

The health effects of air pollution are significant. It is a leading risk factor for death, contributing to one in ten deaths globally. The specific health risks include respiratory infections, lung cancer, heart disease, stroke, and chronic obstructive pulmonary disease (COPD). Air pollution is also associated with the development of respiratory illnesses such as asthma, bronchitis, and emphysema.

WHO has developed strategies to raise awareness about the risks of air pollution and provide solutions to mitigate exposure. The organization monitors and reports on global trends and changes in health outcomes associated with actions taken to address air pollution at the national, regional, and global levels. Despite these efforts, air pollution remains a significant challenge, with death rates varying across different regions.

Outdoor air pollution is a major health risk

WHO data reveals that 99% of the global population breathes air that exceeds the organization's guideline limits and contains high levels of pollutants. This figure varies across regions, with Central and South Asia among the most polluted areas in the world. Low- and middle-income countries suffer the highest exposures, with 89% of premature deaths occurring in these regions.

Outdoor air pollution is caused by various sources, including industrial facilities, motor vehicles, household combustion devices, and forest fires. Pollutants of major concern include particulate matter (such as PM2.5 and PM10), carbon monoxide, ozone, nitrogen dioxide, and sulfur dioxide. These pollutants can have both short-term and long-term effects on human health. Short-term effects include respiratory discomfort, difficulty breathing, chest pain, and irritation of the eyes, nose, and throat. Long-term exposure can lead to lung tissue damage, cancer, early death, and the development of respiratory illnesses such as asthma, bronchitis, and emphysema.

To address the health risks associated with outdoor air pollution, the WHO has developed strategies to raise awareness and provide solutions. The organization monitors and reports on global trends and changes in health outcomes related to actions taken to mitigate air pollution. Additionally, the WHO Global air quality guidelines (AQG) offer guidance on thresholds and limits for key air pollutants, along with interim targets to promote a gradual shift towards lower pollutant concentrations.

The impact of outdoor air pollution is not limited to health risks but also contributes to the global disease burden, affecting both the quantity and quality of life. It is a significant environmental health problem that demands attention and action from governments, industries, and individuals alike.

Household air pollution is a significant concern

WHO data reveals that 99% of people worldwide breathe air that exceeds the organization's guideline limits and contains high levels of pollutants, with low- and middle-income countries suffering the highest exposures. The organization's air quality database compiles ground measurements of annual mean concentrations of nitrogen dioxide (NO2) and particulate matter (PM10 and PM2.5) in over 600 human settlements across more than 100 countries.

The sources of indoor air pollution vary by location, but household combustion devices, such as those used for cooking, heating, and lighting, are a significant contributor. In 2014, WHO issued health-based guidelines on clean fuels and technologies for household cooking, heating, and lighting to address this issue. Despite these efforts, indoor air pollution remains a critical issue, with 89% of premature deaths attributable to combined ambient and household air pollution occurring in low- and middle-income countries.

The impact of household air pollution on health is significant. Particulate matter, such as PM2.5, can penetrate deep into the lungs and even enter the bloodstream, causing long-term health issues such as lung tissue damage, cancer, and the development of respiratory illnesses like asthma. The combined effects of ambient and household air pollution are associated with an estimated 6.7 million premature deaths annually. While the death rates from total air pollution have declined in recent decades, this improvement is primarily due to the reduction in indoor air pollution.

Addressing household air pollution is crucial for improving global health outcomes. WHO has developed strategies to raise awareness about the risks of air pollution and provide solutions to mitigate exposure. These include supporting cleaner household energy sources and promoting access to clean household energy, which can significantly reduce ambient air pollution in certain regions.

WHO provides guidance and support to address air pollution

Air pollution is a pressing global issue, with almost 99% of the world's population exposed to air pollution levels that put them at an increased risk of diseases, including heart disease, stroke, chronic obstructive pulmonary disease, cancer, and pneumonia. The World Health Organization (WHO) is actively working to address this issue by providing guidance and support to its member states.

WHO provides technical support to its member states, aiding in the development of normative guidance, tools, and the provision of authoritative advice on health issues related to air pollution and its sources. WHO also monitors and reports on global trends and changes in health outcomes associated with actions taken to address air pollution at the national, regional, and global levels. This includes the creation and implementation of strategies to raise awareness about the risks of air pollution and the available solutions to mitigate these risks.

WHO has developed various tools and resources to assist in addressing air pollution. The APHT toolkit for health workers, for example, is a comprehensive set of training materials that explores different air pollution and health topics. The WHO Household Multiple Emission Sources (HOMES) model helps policymakers and program planners determine household air pollution levels and make informed decisions. Additionally, the WHO Air Quality, Energy, and Health Science and Policy Summaries (SPS) provide concise overviews of current knowledge and evidence on relevant topics.

WHO also maintains an Air Quality Database, which compiles data on ground measurements of annual mean concentrations of nitrogen dioxide (NO2) and particulate matter (PM10 and PM2.5). This database represents over 600 human settlements in more than 100 countries and is used to derive the Sustainable Development Goal Indicator 11.6.2 for air quality in cities. The Global air quality guidelines (AQG) offer additional global guidance, providing thresholds and limits for key air pollutants that pose health risks. These guidelines are developed through a transparent, evidence-based decision-making process and include interim targets to promote a gradual shift towards lower pollutant concentrations.

Furthermore, WHO supports countries by providing evidence, building institutional capacity, and leveraging the health argument to convene sectors to tackle air pollution. WHO's Air Quality and Health Unit works across three cross-cutting areas: knowledge, evidence, and measuring progress. By recognizing the urgency of the problem, all WHO Member States approved resolution A68.8, "Health and the Environment: Addressing the Health Impact of Air Pollution," at the World Health Assembly in 2015. This resolution was complemented by a roadmap for action the following year.

Air pollution monitoring and data collection

Air pollution is a serious global health issue, with almost 99% of the world's population exposed to air pollution levels that put them at increased risk of disease and early death. The World Health Organization (WHO) defines air pollution as the contamination of the indoor or outdoor environment by any chemical, physical, or biological agent that modifies the natural characteristics of the atmosphere. It is caused by a variety of sources, including household combustion devices, motor vehicles, industrial facilities, and forest fires, with particulate matter, carbon monoxide, ozone, nitrogen dioxide, and sulfur dioxide being major pollutants of concern.

WHO plays a crucial role in monitoring and addressing air pollution through its Air Pollution Data Portal. This portal includes Burden of Disease statistics, air quality databases, and modelled exposure estimates for both ambient and household air pollution. WHO collects data on ground measurements of annual mean concentrations of nitrogen dioxide (NO2) and particulate matter (PM10 and PM2.5) from over 600 human settlements in more than 100 countries. These measurements aim to represent the average air quality for entire cities or towns. While there are thousands of locations worldwide where PM is measured, some geographical areas have little or no monitoring, requiring additional data for high-resolution global estimates.

The organization also provides technical support to its member states, offering guidance, tools, and advice on health issues related to air pollution. WHO actively monitors and reports on global trends and changes in health outcomes associated with actions taken to address air pollution at the national, regional, and global levels. Their global air quality guidelines (AQG) provide valuable thresholds and limits for key air pollutants, along with interim targets to promote a gradual shift towards lower pollutant concentrations.

WHO has developed and implemented strategies to raise awareness about the risks of air pollution and the available solutions. Through digital outreach and partnerships, they have engaged with various stakeholders, including health and environment ministries and city governments, to emphasize the importance of addressing air pollution for both health and environmental benefits. WHO's efforts extend beyond data collection and monitoring, aiming to drive tangible actions and policies that can mitigate the adverse impacts of air pollution on human health and the environment.

WHO's work in air pollution monitoring and data collection is instrumental in informing global health policies and initiatives. By providing evidence-based guidelines and raising awareness, WHO plays a pivotal role in mitigating the health risks associated with air pollution and driving global efforts toward cleaner air and improved public health outcomes.

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