Human Activities And Air Pollution Sources

Air pollution is responsible for nearly seven million deaths worldwide each year, according to the World Health Organization (WHO). The majority of human-caused air pollution comes from energy use and production, with 79% of emissions in 2021 being carbon dioxide, mostly from burning fossil fuels. These fossil fuels are burned to power vehicles, heat homes, and run factories, and include coal, gasoline, and natural gas. Other sources of air pollution include cigarette smoke, industrial processes, and agricultural activities.

Burning fossil fuels

The burning of fossil fuels emits a range of pollutants that reduce air quality and have detrimental effects on human health and the environment. These pollutants include greenhouse gases, such as carbon dioxide (CO2) and nitrous oxide (N2O), which intensify the greenhouse effect. The greenhouse effect traps heat in the Earth's atmosphere, leading to global warming and climate change. The increased atmospheric temperature causes rising sea levels, more frequent and severe extreme weather events, heat-related deaths, and the increased transmission of infectious diseases. According to the National Oceanic and Atmospheric Administration, the cost of extreme weather events in the United States between 2016 and 2020 was estimated at $606.9 billion.

In addition to greenhouse gases, the burning of fossil fuels releases pollutants such as sulfur dioxide, nitrogen oxides, and airborne particles like soot. These pollutants contribute to the formation of smog, which can irritate the eyes, throat, and lungs, particularly in vulnerable individuals such as children and the elderly. Poor air quality caused by these pollutants can lead to respiratory diseases and other health issues, including asthma, cancer, heart disease, and premature death. Globally, one in five deaths is attributed to fossil fuel pollution, with 350,000 premature deaths in the United States in 2018 linked to it.

Furthermore, sulfur dioxide and nitrogen oxide particles in the air combine with water and oxygen to create acid rain, which has detrimental effects on the environment. Acid rain damages plants by altering soil composition, degrades water quality in freshwater sources, and harms crops and young trees. It can also cause the decay of buildings and monuments. The burning of fossil fuels has been linked to preterm birth and low birth weight, impacting neurodevelopmental disorders in children. Additionally, it contributes to environmental injustice, disproportionately affecting the young, the poor, and certain minorities, especially in developing countries.

The combustion of fossil fuels has far-reaching consequences, impacting both human health and the environment. It is essential to recognize the role of burning fossil fuels in air pollution to address this issue and implement measures to reduce our reliance on them and transition towards cleaner and more sustainable energy sources.

Industrial processes

The Clean Air Council has highlighted the need to address air pollution from fracking-related infrastructure, steel-making plants, petrochemical plants, and hazardous waste sites. The extraction of ethane in Pennsylvania, for example, has led to the construction of a new large-scale petrochemical plant, with potential plans for more. The Council advocates for a transition away from natural gas and fossil fuels, as well as a reduction in single-use plastic products and the development of non-fossil fuel-based alternatives.

Industrial activities emit large amounts of organic compounds, carbon monoxide, hydrocarbons, and chemicals into the air. Carbon dioxide, a greenhouse gas, is of particular concern as it traps heat in the Earth's atmosphere, leading to global warming and climate change. According to John Walke, the director of the Clean Air team at NRDC, "most air pollution comes from energy use and production." This includes the burning of fossil fuels for transportation, heating homes, and running factories.

To mitigate industrial air pollution, various technologies and strategies can be employed, including CO2 sequestering, industrial energy efficiency, improved combustion processes, and reduced gas production from agricultural cultivations. Additionally, regulatory measures, such as the Clean Air Act in the United States, aim to safeguard public health by regulating harmful emissions.

Vehicle emissions

Motor vehicles, such as cars, trucks, and motorcycles, emit a range of pollutants through their tailpipe emissions. These emissions contain toxic substances such as nitrogen oxides (NOx), volatile organic compounds (VOCs), and particulate matter (PM). Nitrogen oxides contribute to the formation of ground-level ozone, a major component of smog, which can irritate the eyes and throat and damage the lungs. Particulate matter, on the other hand, consists of tiny particles of chemicals, soil, smoke, dust, or allergens that can be carried in the air and inhaled, posing risks to human health.

The transportation sector also contributes to the emission of air toxics, which are compounds known or suspected to cause cancer and other serious health issues. Examples of mobile source air toxics include benzene, formaldehyde, and diesel particulate matter. Additionally, vehicles burning fossil fuels release carbon dioxide, a major greenhouse gas, contributing to global warming and climate change.

Efforts to reduce vehicle emissions have been undertaken by organizations like the EPA, which has set stringent emissions standards for passenger vehicles, heavy-duty trucks, and buses. These standards include limits on the amount of sulfur in gasoline, which helps reduce nitrogen oxide emissions. The California Air Resources Board (CARB) is another example, working to advance research and implement policies to reduce emissions from on-road and off-road vehicles.

The impact of these initiatives has been positive, with significant reductions in mobile source air toxic emissions. Since 1970, when the EPA started regulating emissions, air quality has improved, and the health of Americans has benefited. By 2030, the EPA projects that its air quality emissions standards for vehicles will prevent even more emissions and improve public health.

Energy production

According to John Walke, the director of the Clean Air team at NRDC, "most air pollution comes from energy use and production." This is supported by research that has found a positive correlation between air pollution and electricity production. Studies have shown that power generation, especially coal-fired power plants, can have adverse effects on air quality. The burning of coal, in particular, has been linked to increased emissions of air pollutants.

In addition to carbon dioxide, the burning of fossil fuels also releases methane, which is a more potent greenhouse gas. While carbon dioxide is released in larger amounts, methane has a much stronger impact on the atmosphere. This is due to its ability to trap heat energy, leading to rising temperatures and the hallmarks of climate change, such as rising sea levels and more extreme weather conditions.

To address the issue of air pollution from energy production, some countries have implemented regulations and plans to reduce emissions. For example, China has implemented a strict Clean Air Action Plan since 2013, which has tightened emission limits for power plants, especially coal-fired ones. However, it is important to note that even renewable power generation, such as hydroelectric, nuclear, wind, and solar power, can still lead to some air pollution, although it may be less than that produced by fossil fuels.

Overall, energy production, specifically the burning of fossil fuels, is a major contributor to air pollution, and efforts to reduce emissions and transition to cleaner energy sources are crucial to mitigate the impacts on human health and the environment.

Agriculture

Agricultural air pollution comes mainly in the form of ammonia, which enters the air as a gas from heavily fertilised fields and livestock waste. Livestock manure and chemicals comprise 95% of ammonia emissions, which in turn account for 58% of the particulate matter air pollution in European cities. In addition, emissions from tractors and farm vehicles, particularly those associated with animal-raising operations, also contribute to air pollution. Cattle, pig, and chicken operations release methane, nitrous oxide, and ammonia into the air. These gases can impact the environment and pose a danger to human health.

Agricultural air pollution also has a significant impact on water quality. Vast quantities of excess fertilizers wash off fields each year, polluting huge watersheds. For example, each summer an oxygenless "dead zone" spreads from the mouth of the Mississippi River, fuelled by excess nitrogen from upstream.

The effects of air pollution on agriculture are also visual. A term called "yellowing" refers to reduced growth, injury, or premature crop death. According to the UN Food and Agriculture Organization, crop yields of staples like rice, maize, and wheat will decrease by up to 10% per degree Celsius of global warming.

Tackling agriculturally-caused air pollution is imperative for the food system and global food security. Implementing sustainable agricultural practices and reducing the use of fertilizers and pesticides can help improve air quality and mitigate the effects of climate change on agriculture.

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