The Air We Breathe: Human Causes Of Pollution

Air pollution is a major threat to global health and prosperity, causing more than 6.5 million deaths each year worldwide. It is caused by the release of harmful gases and chemicals into the air, including solid and liquid particles called aerosols, which are detrimental to human health and the planet. These pollutants are emitted through human activities such as burning fossil fuels, vehicle exhaust fumes, and emissions from agriculture and industry. The effects of air pollution on human health vary depending on the type of pollutant, length and level of exposure, and individual health risks. Vulnerable groups, such as children and older people, are at an increased risk of developing health issues due to air pollution.

Burning fossil fuels

The burning of fossil fuels releases a range of harmful pollutants into the atmosphere, including carbon dioxide, sulfur dioxide, nitrogen oxides, and airborne particles such as soot. These emissions have both direct and indirect impacts on air quality and human health. The carbon dioxide released from burning fossil fuels is a significant driver of climate change, acting as a greenhouse gas that traps heat in the atmosphere, leading to global warming and altered weather patterns. The warming effect is exacerbated by other emitted greenhouse gases, such as nitrous oxide. These gases can remain in the atmosphere for decades to centuries, prolonging their impact.

Airborne particles, including soot and sulfate aerosols, contribute to air pollution and have both local and global effects. While these particles can increase the reflectivity of the atmosphere, leading to a slight cooling effect, their overall impact is warming due to the dominance of the greenhouse effect. Additionally, these particles can cause respiratory issues and other health problems, particularly in vulnerable populations such as children and communities of color. The combustion of fossil fuels has been linked to various health issues, including asthma, cancer, and heart disease. It is also a significant contributor to premature deaths worldwide, with air pollution from burning fossil fuels responsible for about one in five deaths globally.

Furthermore, the burning of fossil fuels has led to ocean acidification, as the ocean absorbs a significant portion of the emitted carbon dioxide, causing a rise in ocean acidity. This, in turn, threatens marine life and ecosystems. The extraction, transportation, and refining of fossil fuels also carry risks, including oil spills that harm wildlife, destroy habitats, and contaminate water sources. Water pollution is further exacerbated by the toxic wastewater generated during fracking processes, which can contain harmful substances such as arsenic, lead, and mercury.

The impact of burning fossil fuels extends beyond environmental damage, as it also contributes to global inequality and environmental injustice. Vulnerable communities, particularly those with high poverty rates and communities of color, bear a disproportionate burden of the health and economic impacts of air pollution. It is crucial to address these disparities and reduce the consumption of fossil fuels to mitigate the far-reaching consequences on both the environment and human well-being.

Vehicle exhaust fumes

Transportation is a major source of air pollution and emissions that contribute to climate change. Cars, trucks, and buses powered by fossil fuels emit nitrogen oxides, which form ground-level ozone and particulate matter. These pollutants can cause lung irritation and weaken the body's defenses against respiratory infections such as pneumonia and influenza. In addition, the combustion of fossil fuels produces carbon monoxide, an odorless, colorless, and poisonous gas that blocks oxygen from reaching the brain, heart, and other vital organs when inhaled.

Motor vehicles also emit sulfur dioxide by burning sulfur-containing fuels, especially diesel and coal. Sulfur dioxide can react in the atmosphere to form fine particles, posing significant health risks, especially to young children and asthmatics. Furthermore, vehicles emit pollutants, predominantly carbon dioxide, which contribute to global climate change. While carbon dioxide is not regulated as an air pollutant, it is the transportation sector's primary contribution to climate change and is essentially proportional to fuel consumption.

Industrial emissions

Industrial facilities emit a wide range of pollutants, including particulate matter, sulfur dioxide, nitrogen oxides, and other toxic chemicals. These pollutants have severe health implications, including respiratory diseases, cancers, decreased lung function, and asthma. Additionally, they contribute to environmental degradation, such as acid rain and climate change. The release of greenhouse gases, such as carbon dioxide and methane, leads to global warming, rising sea levels, extreme weather events, and adverse health consequences like heat-related deaths.

The impact of industrial emissions on human health is significant, especially for residents in industrial townships. Long-term exposure to these pollutants can cause respiratory and cardiovascular diseases, as well as cancers. Vulnerable communities, including racial and ethnic minorities, individuals with limited education, and those experiencing poverty, are disproportionately affected by carcinogenic industrial emissions. This disparity is influenced by historical factors such as racist zoning policies and discriminatory lending practices.

Furthermore, the abundant discharge of industrial toxins has detrimental effects on both the physical and biological environment. Heat and pollutants released from industrial processes, such as vapors, aerosols, solid particles, and toxic gases, contribute to environmental instability and discomfort. The complex interaction of dispersion and emission from manufactories results in air pollution levels that exceed the recommended standards, making it an unavoidable product of the current industrial era.

While complete removal of industrial emissions is challenging, implementing ambient air pollution control technologies can be a game-changing solution. Additionally, a transition away from natural gas and fossil fuels, along with improved recycling practices and the development of non-fossil fuel-based alternatives, can help mitigate the impacts of industrial emissions on air pollution.

Wildfires

The particles are made up of different components, including acids (e.g. sulfuric acid), inorganic compounds (e.g. ammonium sulfate), organic chemicals, soot, metals, soil, or dust particles. The intense heat generated by wildfires can also cause the release of pollutants from the soil, such as mercury and other heavy metals, which can be transported through the air and deposited in other areas, leading to environmental contamination.

The smoke particles can affect the formation of clouds and precipitation, potentially leading to changes in rainfall patterns. They can also alter the amount and distribution of solar radiation reaching the Earth's surface, which can impact the formation of weather systems and the behaviour of storms.

In 2021, a study found that wildfire smoke caused over 33,000 deaths across 43 countries in a single year. Exposure to wildfire smoke can lead to a range of health issues, especially for children, the elderly, pregnant women, and people with heart or respiratory conditions. These sensitive groups are advised to limit outdoor activities when the Air Quality Index (AQI) reaches unhealthy levels. When air quality deteriorates due to wildfire smoke, it is recommended to stay indoors with windows and doors closed, and to set air conditioning systems to 'on' to ensure constant air filtration.

Climate change

Air pollution includes greenhouse gases such as carbon dioxide, which remain in the atmosphere for years. The increase in greenhouse gases comes from vehicle exhaust, pollutants from factories and power plants, emissions from agriculture, and other sources. These gases trap heat from the sun in the Earth's atmosphere, causing the climate to warm. Warmer temperatures can also increase ground-level ozone, a harmful greenhouse gas and health hazard, and prolong the summer smog season.

Additionally, climate change can cause heatwaves and droughts, which negatively impact air quality. Heatwaves can create stagnant air that concentrates air pollutants, and droughts can increase particulate matter in the air. These extreme weather events can also increase the occurrence of wildfires.

Frequently asked questions