Air Pollution: What You Need To Know

Air pollution is a major threat to global health and prosperity, causing around 7 or 8 million deaths each year. It is caused by the release of pollutants into the air, which are detrimental to human health and the planet. These pollutants can be gases like ozone or nitrogen oxides, small particles like soot or other chemicals like lead. They are released into the air by human activities such as burning fossil fuels for industry, construction, transportation, and heating, as well as natural sources such as wildfires, dust storms, and volcanic eruptions. Air pollution is most common in large cities, where emissions from many different sources are concentrated, and it poses a significant risk factor for a number of diseases, including stroke, heart disease, respiratory issues, asthma, and lung cancer.

Health risks: respiratory disease, cardiovascular disease, neurological damage, cancer, and death

Air pollution is linked to a range of serious health issues, including respiratory disease, cardiovascular disease, neurological damage, cancer, and death.

Respiratory diseases are a common outcome of air pollution exposure. Particle pollution can cause cellular injury and systemic inflammation, affecting the lungs and other organs. This can lead to worsened symptoms for those with pre-existing conditions like asthma, COPD, and lung cancer. In addition, the immune system's response to respiratory infections is weakened by air pollution, increasing the risk of severe illness and death, especially in older adults.

Cardiovascular diseases, including heart disease and stroke, are also influenced by air pollution. Particle pollution, particularly PM2.5, increases the risk of cardiovascular events and mortality. The evidence is strong for outdoor particle pollution, with fine particulate matter penetrating indoor spaces and causing adverse health effects. The mechanisms include the buildup of plaque in arteries, which can result in blood clots and heart attacks.

Neurological damage is another consequence of air pollution exposure. Nitrogen dioxide (NO2), a prevalent air pollutant, is associated with cognitive decline, neurodegeneration, and an increased risk of Parkinson's disease, Alzheimer's disease, and other dementias. Studies have shown that air pollution induces oxidative stress and inflammation in the brain, leading to neuronal damage and adverse cognitive effects, especially in elderly populations.

Air pollution has also been linked to an increased risk of cancer. Studies have found a connection between high levels of particulate air pollution and increased incidence of breast cancer. Additionally, long-term exposure to fine particle pollution is associated with an elevated risk of lung cancer, even in those who have never smoked.

Lastly, air pollution contributes to premature death. Fine particulate matter pollution caused approximately 4.14 million deaths worldwide in 2019. It is estimated that air pollution exposure reduces the average person's lifespan by 1.8 years. The impact is especially severe on young children and older adults, with 709,000 deaths in children under five attributed to air pollution in 2021.

Sources: car exhaust, factories, dust, pollen, volcanoes, and wildfires

Air pollution is a significant environmental health hazard that affects human health and the planet. It refers to the release of pollutants into the air, which can be in the form of solid and liquid particles, called "aerosols", or certain gases. These particles and gases can come from car exhaust, factories, dust, pollen, mould spores, volcanoes, and wildfires.

Car exhaust emissions are a significant contributor to air pollution, with vehicles that have petrol and diesel engines producing about half of their emissions from exhaust gas. The other half comes from non-exhaust emissions, such as tyre and brake wear. Electric vehicles produce no tailpipe emissions but still contribute to non-exhaust emissions. Additionally, diesel trains, ships, and planes also cause air pollution.

Factories and industrial processes are another major source of air pollution. Coal- and oil-burning power plants, residential heating systems, and manufacturing processes such as iron, steel, and rubber product production release harmful gases and particles into the air. The burning of fossil fuels, such as fuel oil, gasoline, and natural gas, is a significant contributor to the emission of nitrogen oxides (NOx), particularly nitrous oxide (NO), which can form acid rain and cause nutrient pollution in water. Nitrogen dioxide (NO2), a toxic gas, is formed from NO reacting with other atmospheric gases.

Wildfires can also significantly impact air quality, with smoke making up almost 75% of all air pollution by concentration during active fires. Additionally, agricultural practices, such as burning fields to clear post-harvest crop remnants, contribute to poor air quality. This can have detrimental effects on the health of children, increasing their risk of respiratory issues and asthma.

Volcanoes are natural sources of air pollution, emitting steam, carbon dioxide, sulfur dioxide, and small amounts of other pollutants during eruptions.

Dust and pollen are also listed as sources of air pollution, though their impact is less severe compared to other sources. However, pollen and other forms of particulate matter can still affect air quality and have potential health implications for those with allergies or respiratory conditions.

Effects: smog, haze, acid rain, and water pollution

Air pollution is a major threat to global health and prosperity, causing more than 6.5 million deaths annually worldwide. According to the World Health Organization (WHO), 99% of humans currently breathe air that exceeds the safe limits for pollutants, with those in low- and middle-income countries suffering the most.

Smog

Smog is a mixture of smoke and fog that often contains pollutants such as smoke, nitrogen oxides, and carbon monoxide. It is a significant issue in areas with high traffic and industrial activity. Smog can irritate the eyes, nose, and throat, leading to respiratory problems and other health issues. In 1952, a severe smog event in London caused over 4,000 deaths.

Haze

Haze is a suspension of fine particles and droplets in the lower atmosphere that reduces visibility. It is often caused by pollutants such as nitrogen oxides, sulfur dioxide, and particulate matter. Haze can have adverse effects on human health, particularly for those with respiratory and cardiovascular conditions.

Acid Rain

Acid rain occurs when sulfur dioxide and nitrogen dioxide mix with water droplets in the atmosphere, forming sulfuric acid and nitric acid. These acidic pollutants can fall as rain, snow, or dry particles, damaging buildings, statues, and other structures. Acid rain also impacts natural environments, increasing the acidity of soils and water bodies, harming vegetation, and threatening aquatic ecosystems.

Water Pollution

Water pollution is a significant consequence of air pollution. Nitrogen oxides and sulfur dioxide, which contribute to acid rain, can fall onto water bodies, increasing their acidity. This process, known as acidification, can harm aquatic life, including fish and other wildlife. Additionally, nitrogen pollution in coastal waters can have detrimental effects on marine ecosystems.

Prevention: renewable energy, nuclear power, sustainable transport, improved vehicle technology

Air pollution is the emission of pollutants into the air that are detrimental to human health and the planet. According to the World Health Organization (WHO), air pollution is responsible for the deaths of millions of people worldwide annually. As the world navigates the challenges of climate change and its impact on respiratory health, there is a growing emphasis on preventive measures, including the adoption of renewable energy, nuclear power, sustainable transport, and improved vehicle technology.

Renewable energy sources, such as wind, solar, and geothermal power, are naturally replenished and emit little to no greenhouse gases or pollutants into the atmosphere. The abundance of these energy sources makes them readily accessible, and their increasing popularity is driving down costs. The UN estimates that by 2030, renewable energy sources could provide 65% of the world's electricity supply, significantly reducing carbon emissions and improving air quality.

Nuclear power, another low-carbon energy source, also plays a crucial role in preventing air pollution. Nuclear power plants emit virtually no air pollutants during their operation, and unlike coal, oil, or gas, they do not release greenhouse gases. Historical data reveals that nuclear power has prevented over 60 gigatons of net GHG emissions globally in the past 50 years, averting approximately 2 million deaths that could have resulted from air pollution.

To address air pollution effectively, a shift towards sustainable transport is imperative. Transport is responsible for nearly a quarter of global energy-related carbon dioxide emissions, and the demand for transport is projected to double between 2005 and 2050. Sustainable transport initiatives, such as the UNEP's "Share the Road" campaign, advocate for the systematic inclusion of non-motorized transport infrastructure in urban areas. This promotes walking, cycling, and the use of public transportation, reducing the number of vehicles on the road and, consequently, lowering emissions.

Improved vehicle technology has also been instrumental in combating air pollution. Over the years, new passenger vehicles have become significantly cleaner, with emissions of common pollutants decreasing by up to 99% compared to models from the 1960s and 1970s. Regulatory standards and innovations in the vehicle emissions control industry have driven these improvements, leading to healthier air and improved public health outcomes.

Health improvements: reduced air pollution saves billions in health costs annually

Air pollution is a major threat to global health and prosperity. According to the World Health Organization (WHO), indoor and outdoor air pollution is responsible for nearly seven million deaths worldwide each year. People in low- and middle-income countries suffer the most, with 99% of human beings currently breathing air that exceeds the WHO's guideline limits for pollutants. In the United States, people of color are 1.5 times more likely to live in areas with poor air quality, due to racist zoning policies and discriminatory lending practices. Living near polluting sites increases the risk of respiratory disease, cardiovascular disease, neurological damage, cancer, and death.

The main sources of outdoor air pollution include road vehicles, diesel trains, ships, and planes, agricultural emissions, and meat production or livestock. For example, methane is emitted by the digestion of food by cattle, causing ground-level ozone. Certain agricultural practices, such as burning fields to clear post-harvest crop remnants, contribute to poor air quality and asthma in children. During wildfires, smoke can make up almost 75% of all air pollution by concentration.

To reduce air pollution, individuals can make better choices about transportation, such as walking, biking, or taking public transportation. They can also choose more fuel-efficient vehicles or buy electric cars. Supporting leaders who push for clean air and water and responsible steps on climate change is crucial. Additionally, buying local food can cut down on the fossil fuels burned in trucking or flying food in from other parts of the world.

On a larger scale, transitioning to renewable energy or nuclear power in the power sector is a very effective way to reduce air pollution. A 2015 study found that switching to 100% renewable energy in the United States would eliminate about 62,000 premature deaths per year and save about $600 billion in health costs annually by 2050. Similarly, the report "The Costs of Inaction: The Economic Burden of Fossil Fuels and Climate Change on Health in the United States" found that the cost of inaction on climate change results in more than $820 billion in health costs each year from fossil fuel air pollution and climate change impacts. These costs include premature deaths, hospitalizations, serious injuries, mental health ailments, lost wages, and missed days of work. By taking bold action to cut fossil fuel use and climate pollution, hundreds of billions of dollars could be saved in avoided health harms.

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