Air and Climate: Air Pollution Exposure
Air pollution exposure is a major environmental and health issue that affects millions of people around the world. According to the World Health Organization, air pollution is responsible for nearly seven million deaths each year globally.
Air pollution exposure refers to the amount and duration of contact with harmful substances in the air, such as fine particulate matter (PM2.5), ozone, nitrogen oxides, sulfur oxides, and volatile organic compounds. These pollutants can cause various respiratory and cardiovascular diseases, as well as cancer and other chronic conditions.
Fine Particulate Matter (PM2.5)
Fine particulate matter (PM2.5) is the air pollutant that poses the greatest risk to health globally, affecting more people than any other pollutant. PM2.5 is composed of tiny particles that are 30 times thinner than a human hair.
These particles can penetrate deep into the lungs and bloodstream, causing inflammation and oxidative stress. PM2.5 can also affect the brain, the nervous system, and the reproductive system. PM2.5 is mainly produced by combustion processes, such as vehicle emissions, power plants, industrial boilers, and biomass burning.
The OECD Air Pollution Exposure Indicator measures the percentage of population exposed to PM2.5 levels above 10 micrograms per cubic meter, which is the annual average guideline value recommended by the WHO. The indicator shows that in 2019, 58% of the OECD population was exposed to PM2.5 levels above this threshold, with the highest exposure rates in Chile, Mexico, Turkey, and Korea. The indicator also shows that the exposure to PM2.5 has decreased by 15 percentage points since 2005, mainly due to the implementation of air quality policies and regulations in many OECD countries.
Ozone
Ozone is a gas that is beneficial in the upper atmosphere, where it protects the Earth from harmful ultraviolet radiation. However, ozone is harmful when it is present at ground level, where it is a major component of smog. Ground-level ozone is formed by the chemical reaction of nitrogen oxides and volatile organic compounds in the presence of sunlight. These precursors are emitted by various sources, such as vehicles, power plants, industrial facilities, and solvents.
Ground-level ozone can irritate the eyes, nose, and throat, and cause breathing difficulties, coughing, and chest pain. Ozone can also aggravate asthma and other respiratory diseases, and reduce lung function and capacity. Ozone can also damage crops and vegetation, reducing their growth and yield.
The OECD Air Quality and Health Indicator measures the population-weighted average of the annual maximum daily eight-hour average ozone concentration across the OECD countries. The indicator shows that in 2019, the average ozone concentration was 48.6 parts per billion, which is below the WHO guideline value of 51 parts per billion. However, the indicator also shows that the ozone concentration has increased by 4.4% since 2005, indicating a worsening trend of ozone pollution in the OECD area.
Other Indicators of Air and Climate
In addition to PM2.5 and ozone, there are other indicators that can provide information on the state and trends of air and climate. For example, the EPA Climate Change Indicators report presents more than 50 indicators that show the causes and effects of climate change in the United States and globally. Some of these indicators are related to air pollution, such as greenhouse gas emissions, atmospheric carbon dioxide concentrations, and air temperature.
Other indicators are related to the impacts of climate change on weather and climate, such as precipitation, storms, floods, droughts, heat waves, and sea level rise. These indicators can help us understand the linkages between air pollution and climate change, and the implications for human health and the environment.
Nitrogen Oxides
Nitrogen oxides (NOx) are a group of gases that consist of nitrogen and oxygen, such as nitric oxide (NO) and nitrogen dioxide (NO2). NOx are mainly emitted by combustion processes, such as vehicles, power plants, industrial boilers, and biomass burning. NOx can react with other pollutants in the air, such as volatile organic compounds, to form ozone and secondary particulate matter. NOx can also contribute to acid rain and eutrophication of water bodies.
NOx can have adverse effects on human health and the environment. NOx can irritate the respiratory system, cause bronchitis, asthma, and emphysema, and increase the risk of lung infections and cancer. NOx can also damage vegetation, reduce crop yields, and impair the photosynthesis process.
The OECD Air and Climate Indicator measures the total emissions of NOx from all sources in the OECD countries. The indicator shows that in 2019, the total NOx emissions were 14.6 million tonnes, which is a 38% decrease since 2005. The indicator also shows that the main sources of NOx emissions in the OECD area are road transport (40%), energy production and distribution (23%), and industry (18%).
Sulfur Oxides
Sulfur oxides (SOx) are a group of gases that consist of sulfur and oxygen, such as sulfur dioxide (SO2) and sulfur trioxide (SO3). SOx are mainly emitted by combustion processes that use coal, oil, or other fossil fuels that contain sulfur. SOx can also be emitted by industrial processes, such as metal smelting, paper production, and petroleum refining. SOx can react with other pollutants in the air, such as water vapor, to form sulfuric acid and secondary particulate matter. SOx can also contribute to acid rain and eutrophication of water bodies.
SOx can have negative impacts on human health and the environment. SOx can irritate the eyes, nose, and throat, and cause coughing, wheezing, and shortness of breath. SOx can also aggravate asthma and other respiratory diseases, and increase the risk of cardiovascular diseases and premature death. SOx can also damage buildings, monuments, and cultural heritage, and reduce the visibility and aesthetic value of the landscape.
The OECD Air and Climate Indicator measures the total emissions of SOx from all sources in the OECD countries. The indicator shows that in 2019, the total SOx emissions were 5.4 million tonnes, which is a 64% decrease since 2005. The indicator also shows that the main sources of SOx emissions in the OECD area are energy production and distribution (49%), industry (25%), and residential and commercial sectors (12%).
Volatile Organic Compounds
Volatile organic compounds (VOCs) are a group of chemicals that are emitted as gases from various sources, such as paints, solvents, cleaners, fuels, cosmetics, and pesticides. VOCs can also be produced by natural sources, such as plants, animals, and microorganisms. VOCs can react with other pollutants in the air, such as nitrogen oxides, to form ozone and secondary particulate matter. VOCs can also contribute to indoor air pollution, as they can accumulate in poorly ventilated spaces.
VOCs can have harmful effects on human health and the environment. VOCs can cause eye, nose, and throat irritation, headaches, nausea, and dizziness. VOCs can also affect the central nervous system, the liver, the kidneys, and the reproductive system. VOCs can also increase the risk of cancer and other chronic diseases. VOCs can also damage vegetation, reduce crop yields, and impair the photosynthesis process.
The OECD Air and Climate Indicator measures the total emissions of non-methane VOCs from all sources in the OECD countries. The indicator shows that in 2019, the total non-methane VOC emissions were 9.8 million tonnes, which is a 34% decrease since 2005. The indicator also shows that the main sources of non-methane VOC emissions in the OECD area are road transport (28%), residential and commercial sectors (25%), and industry (18%).
Greenhouse Gases
Greenhouse gases (GHGs) are a group of gases that trap heat in the atmosphere and cause the greenhouse effect, which is the main driver of global warming and climate change. The most important GHGs are carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and fluorinated gases (F-gases). GHGs are emitted by various human activities, such as fossil fuel combustion, agriculture, land use change, waste management, and industrial processes.
GHGs can have severe impacts on human health and the environment. GHGs can increase the global average temperature, which can lead to more frequent and intense heat waves, droughts, floods, storms, and wildfires. GHGs can also alter the precipitation patterns, which can affect the availability and quality of water resources. GHGs can also cause the melting of glaciers and ice caps, which can raise the sea level and threaten coastal communities. GHGs can also affect the biodiversity and ecosystems, which can reduce the provision of essential services and goods.
The OECD Greenhouse Gas Emissions Indicator measures the total emissions of GHGs from all sources in the OECD countries. The indicator shows that in 2019, the total GHG emissions were 11.9 billion tonnes of CO2 equivalent, which is a 9% decrease since 2005. The indicator also shows that the main sources of GHG emissions in the OECD area are energy production and distribution (35%), road transport (16%), and industry (15%).
Air Quality Policies and Regulations
Air quality policies and regulations are the legal and institutional frameworks that aim to reduce air pollution and protect human health and the environment. Air quality policies and regulations can include various instruments, such as standards, limits, taxes, subsidies, incentives, bans, permits, and enforcement mechanisms. Air quality policies and regulations can be implemented at different levels, such as local, national, regional, and global.
Air quality policies and regulations can have positive impacts on human health and the environment, as well as economic and social benefits. Air quality policies and regulations can prevent or reduce the premature deaths, diseases, and disabilities caused by air pollution. Air quality policies and regulations can also improve the quality of life, well-being, and productivity of the population. Air quality policies and regulations can also reduce the costs of health care, environmental damage, and climate change mitigation and adaptation.
The OECD Environmental Policy Stringency Indicator measures the stringency of air quality policies and regulations in the OECD countries. The indicator shows that in 2019, the average stringency score was 4.1 out of 6, which is a 36% increase since 2005. The indicator also shows that the most stringent countries in terms of air quality policies and regulations were Switzerland, Norway, and Japan. The indicator also shows that the main drivers of policy stringency were the public demand for cleaner air, the international cooperation and commitments, and the technological innovation and diffusion.
Conclusion
Air pollution is a critical issue impacting human health and the environment globally. Policies and regulations are crucial for addressing this challenge, aiming to reduce pollution levels and safeguard public health. The OECD provides valuable indicators to monitor progress in air quality and climate action, offering insights into the effectiveness of measures implemented and highlighting areas for further improvement. These indicators play a vital role in guiding decision-making processes towards a cleaner and healthier future.
