Human Activities And Air Pollution: Who's Responsible?

Air pollution is a significant global health hazard, causing millions of premature deaths annually. It is caused by the release of harmful gases and particles into the air, which can be detrimental to human health and the planet. The primary sources of human-made air pollution are vehicle emissions, fuel oils, natural gas, manufacturing by-products, power generation, and chemical production. Natural sources of air pollution include wildfires, volcanic eruptions, and gases emitted from decomposing organic matter. According to the World Health Organization (WHO), 99% of humans currently breathe air that exceeds the recommended pollutant levels, with those in low- and middle-income countries suffering the most.

Burning fossil fuels

Particulate matter, or PM 2.5, refers to tiny airborne particles that are up to 2.5 microns in diameter. These particles can linger in the air, be easily inhaled, and penetrate deep into the lungs, entering the bloodstream and causing damage to multiple organs. Burning fossil fuels, such as coal and gasoline, produces significant amounts of PM 2.5, including soot. This type of pollution is associated with increased risks of respiratory diseases, strokes, heart diseases, lung cancer, and other health problems.

Nitrogen oxides (NOx) are another significant pollutant emitted from burning fossil fuels. NOx contributes to the formation of smog and acid rain. Fossil fuel combustion in transportation and industrial activities are major sources of NOx emissions. Additionally, ammonia, another nitrogen compound, is released into the air from fossil fuel burning, particularly in the agricultural context.

Greenhouse gas emissions from fossil fuel combustion also contribute to climate change. As the climate crisis intensifies, there is an increase in the production of allergenic air pollutants, including mold and pollen. Climate change-fueled droughts and dry conditions also create favorable conditions for wildfires, which produce smoke that can pollute the air with particulate matter over vast distances.

The health impacts of burning fossil fuels are far-reaching and disproportionately affect certain populations. Children, the elderly, people on low incomes, and individuals in urban areas are particularly vulnerable to the harmful effects of air pollution. Additionally, low- and middle-income countries suffer from higher exposures to air pollution, exacerbating health risks and socioeconomic inequality.

To mitigate the impacts of burning fossil fuels on air pollution, various interventions can be implemented. These include improving energy efficiency, transitioning to renewable energy sources, adopting sustainable land use practices, promoting cleaner household energy and transport, and implementing better waste management systems. By addressing these issues, we can not only reduce air pollution but also contribute to mitigating the climate crisis and improving public health on a global scale.

Industrial facilities

A variety of industrial sources, such as fracking-related infrastructure, steel-making plants, petrochemical plants, and hazardous waste sites, release pollutants that negatively affect public health and contribute to the climate crisis. For example, the ethane extracted in Pennsylvania has led to the construction of a new large-scale petrochemical plant, with the possibility of more to come. The Clean Air Council has called for an end to new petrochemical facilities and a reduction in single-use plastic products, improved recycling, and the development of non-fossil fuel-based plastics.

The natural gas, plastic, chemical, electric generation, and waste disposal industries can generate hazardous waste that must be properly disposed of, often at facilities that create significant air pollution. The burning of fossil fuels, such as coal and petroleum, releases harmful particles and gases into the atmosphere, contributing to air pollution. Additionally, the biomass industry, which manufactures and burns wood pellets, produces harmful pollutants like nitrogen oxides, volatile organic compounds, and microscopic dust particles, impacting the health of residents in southwest Pennsylvania, especially those in Pittsburgh and Allegheny County.

To address industrial air pollution, organizations like the Clean Air Council and SELC work with communities and governments to prevent hazardous waste, oppose waste incineration, and advocate for improved pollution controls. They also challenge deficient air pollution permits and enforcement for facilities that pose significant environmental and health risks. These efforts aim to hold polluting industries accountable and improve air quality for affected communities.

Household combustion devices

Indoor combustion pollutants include a range of toxic gases and particles released during the burning of various fuels. Carbon monoxide (CO), a colourless and odourless gas, is one of the primary indoor combustion pollutants. At elevated levels, carbon monoxide can cause headaches, fatigue, and nausea. Extremely high levels of carbon monoxide can lead to brain and heart damage and even death. Other combustion pollutants, such as nitrogen dioxide, fine and ultrafine particles, polycyclic aromatic hydrocarbons (PAHs), and formaldehyde, can irritate the eyes, nose, and throat. They are also linked to respiratory diseases, lung cancer, and other serious health issues.

The use of unvented combustion appliances, including gas stoves, kerosene heaters, and charcoal grills, is a significant source of indoor air pollution. These appliances release combustion pollutants directly into the home, leading to high indoor air pollutant levels. In particular, using a charcoal grill or a gas stove for home heating can significantly increase indoor air pollution levels. Additionally, wood-burning appliances, such as fireplaces and wood stoves, can release pollutants if not properly maintained and inspected annually.

To mitigate the risks associated with household combustion devices, several guidelines and interventions have been proposed. The World Health Organization (WHO) has developed guidelines for indoor air quality and household fuel combustion, offering recommendations on cleaner fuels and technologies. The California Air Resources Board also provides guidelines for reducing exposure to indoor combustion pollutants, such as using "sealed combustion" or "direct vent" gas appliances and installing carbon monoxide detectors in dwellings with fuel-type appliances.

Furthermore, the transition to cleaner household fuels and technologies is essential for improving air quality and protecting public health. The WHO provides technical support and capacity-building assistance to countries to evaluate and promote the use of health-promoting household fuels and technologies. Additionally, financial incentives are offered to encourage homeowners to replace old, inefficient, and polluting wood-burning appliances with more efficient and cleaner alternatives.

Motor vehicles

Levels of traffic-related air pollution are higher near major roadways that have high traffic volume. Transportation agencies and local jurisdictions can reduce traffic-related air pollution and improve air quality in several ways, including developing cleaner travel options through measures such as expanding public transportation, walking, and bicycling.

Vehicle emissions are not the only source of air pollution from motor vehicles. The refining and distribution of fuels, as well as the manufacturing and disposal or recycling of vehicles, also contribute to air pollution. Pollutants from vehicle exhaust can affect more than just the lungs. Tailpipe pollutants pose health risks at every stage of life and can even cause premature death.

To reduce air pollution from motor vehicles, governments and organizations have implemented various measures and programs. These include supporting the manufacture and sale of zero and low-emission vehicles, promoting the use of clean fuels such as biodiesel, electricity, and hydrogen, and requiring special equipment at gas pumps to recover vapors instead of releasing them into the air.

Forest fires

Wildfire smoke is a mixture of hazardous air pollutants, including particulate matter (PM), ozone, aromatic hydrocarbons, and lead. The fine particulate matter, known as PM2.5, is of particular concern as it can be inhaled deep into the lungs and may even enter the bloodstream. These fine particles from wildfire smoke comprise approximately 90% of the total particle mass. PM2.5 has been linked to various adverse health effects, including respiratory and cardiovascular issues, lung disease, cognitive impairment, and premature death.

The impact of wildfires on air quality can be far-reaching, with particles spreading over hundreds of kilometres from the source of the fires. For example, the 2021 wildfires in western North America led to a surge in PM2.5 levels, peaking at several times the level recommended by the World Health Organization, and affecting areas far beyond the immediate vicinity of the fires.

Climate change is expected to increase the frequency and intensity of wildfires, with experts predicting a potential 50% increase in their numbers by 2100. Warmer temperatures and drier conditions create favourable conditions for wildfires, and the length of the fire season is already extending. As a result, the air pollution caused by wildfires is anticipated to worsen, posing a growing threat to human health and the environment.

To mitigate the impact of wildfires, governments and organizations are implementing preventive measures and developing strategies to reduce the risk of fires. For instance, the Indonesian government is working with local communities to promote alternative methods for clearing land without using fires, and the United Nations Environment Programme (UNEP) has developed a roadmap to reduce emissions and address climate stability.

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