Air Pollution: Understanding The Causes And Effects

Air pollution is a severe environmental health hazard that affects billions of people worldwide. It is caused by solid or liquid particles and certain gases suspended in the air, which can come from vehicle emissions, fuel oils, natural gas, manufacturing by-products, power generation, and chemical production. These pollutants can create haze, making it difficult to see, and have severe health implications, including respiratory diseases, cardiovascular issues, and lung damage. According to the World Health Organization, outdoor and indoor air pollution is responsible for 7 million premature deaths annually. With climate change intensifying the problem, addressing air pollution is crucial for both human health and the planet's well-being.

Vehicle emissions

Greenhouse gas emissions, such as carbon dioxide (CO2), are released when vehicles burn gasoline and other fossil fuels. CO2 is the principal greenhouse gas and is often referred to as a greenhouse gas emission. While CO2 is not inherently harmful and is necessary for life on Earth, human activity has increased its presence in the atmosphere to unmanageable levels. This excess CO2 traps heat from the sun, causing the 'greenhouse effect' and driving climate change. In 2019, the average new light vehicle sold in Australia emitted 181 grams of CO2 per kilometre, and SUVs are a significant contributor to global CO2 emissions.

Air pollutant emissions from vehicle exhausts include toxic pollutants such as carbon monoxide, volatile organic compounds, nitrogen oxides, sulfur dioxide, formaldehyde, benzene, and particulate matter. These emissions contribute to smog formation, which is a mixture of solid and liquid particles and certain gases in the air that reduce visibility and cause respiratory issues. In the United States, vehicle emissions are the largest source of carbon monoxide and nitrogen oxide pollution, with transportation accounting for up to 95% and 45% of these emissions, respectively.

The health impacts of vehicle emissions are significant. Exposure to these pollutants has been linked to asthma, heart and lung disease, dementia, and various types of cancer, particularly in children and individuals living near busy roads or with long commutes. Vehicle emissions have also been associated with mental health issues, including anxiety and depression. In the US alone, an estimated 17,000 to 20,000 deaths occur annually due to vehicle pollution, disproportionately affecting people of colour.

Industrial facilities

Some of the specific industrial facilities contributing to air pollution include refineries, mills, mines, and manufacturing plants. These facilities emit dangerous airborne pollutants such as PM2.5, silica dust, coal dust, methane, carbon monoxide, sulfur dioxide, and nitrogen oxides. The release of these pollutants negatively impacts air quality and poses severe risks to human health. For example, silica dust can lead to silicosis, and coal dust causes black lung disease.

In addition to these direct emissions, industrial facilities also contribute to air pollution through their waste disposal practices. Industries such as natural gas, plastics, chemicals, electric generation, and waste disposal generate hazardous waste that requires proper disposal. However, the disposal process, often involving incineration, can create significant air pollution. Furthermore, inadequate laws and regulations, poor enforcement of environmental standards, and the delayed adoption of sustainable practices further exacerbate the problem of industrial air pollution.

The Clean Air Council is an organization dedicated to addressing industrial air pollution. They work to prevent hazardous waste, oppose waste incineration, and advocate for comprehensive testing of waste streams to identify pollutants. The Council also calls for a transition away from natural gas and fossil fuel-based plastics to reduce greenhouse gas emissions and protect public health.

It is worth noting that industrial air pollution disproportionately affects certain communities. Studies have found that populations experiencing poverty or with lower educational attainment bear a higher burden of exposure to carcinogenic industrial air emissions, regardless of race and ethnicity. This highlights the importance of addressing industrial air pollution to protect the health and well-being of vulnerable populations.

Natural sources

Forest fires, a subset of wildfires, are common sources of air pollution. They release hazardous substances, including particulate matter, carbon monoxide, and nitrogen dioxide, which can have serious health implications.

Another natural source of air pollution is organic compounds from plants, sea salt, and suspended soils and dusts, such as those from the Sahara. These organic compounds can be carried over long distances by the wind, affecting air quality in various regions.

Additionally, animals like cows and sheep contribute to air pollution by releasing large amounts of methane through belching and flatulence. Methane is a colourless gas produced in their stomachs when bacteria break down food. Livestock is the most significant source of methane globally, and it is the second most important greenhouse gas contributing to climate change.

Fuel oils and natural gas

Air pollution is caused by solid or liquid particles and certain gases suspended in the air. These particles and gases can come from car and truck exhaust, factories, dust, pollen, mould spores, volcanoes, and wildfires. It is now the world's fourth-largest risk factor for early death, with 4.5 million deaths linked to outdoor air pollution exposures in 2019, and another 2.2 million caused by indoor air pollution.

Refineries convert crude oil into products such as gasoline, diesel fuel, kerosene, jet fuel, asphalt, and liquefied petroleum gas. They emit pollutants from several sources, including leaks, flames, and excessive emissions. These emissions release dangerous air pollutants or toxicants known or suspected to cause cancer and congenital disabilities. Leaky valves and pumps also cause fugitive VOC emissions.

Natural gas production can also produce large volumes of contaminated water, which requires proper handling, storage, and treatment so that it does not pollute land and other waters. Natural gas wells and pipelines often have engines to run equipment and compressors, which produce air pollutants and noise. In some areas, natural gas produced at oil wells is burned (flared) at well sites because it is not economical to transport for sale or contains high concentrations of hydrogen sulfide, a toxic gas.

Well drilling activities produce air pollution and may disturb people, wildlife, and water resources. Laying pipelines that transport natural gas from wells usually requires clearing land to bury the pipe. The construction and land disturbance required for oil and gas drilling can alter land use and harm local ecosystems by causing erosion and fragmenting wildlife habitats and migration patterns.

Some areas where drilling occurs have experienced increases in concentrations of hazardous air pollutants, including particulate matter and ozone, regulated by the EPA because of their harmful effects on health and the environment. Exposure to elevated levels of these air pollutants can lead to adverse health outcomes, including respiratory symptoms, cardiovascular disease, and cancer.

Forest and wildfires

PM2.5 particles are minuscule, at over 40 times smaller than a grain of sand. However, they can have detrimental effects on human health, even in small amounts. Inhaling these particles can aggravate asthma, trigger lung disease, induce heart attacks, and lead to premature death. The 2021 wildfires in North America and Russia caused PM2.5 levels to spike, with concentrations in Siberia reaching record highs.

Wildfires are often the result of a combination of human activities and natural processes. Human activities, such as burning fossil fuels, transportation, and industrial processes, release greenhouse gases and black carbon emissions, contributing to climate change. Black carbon, a super pollutant released by fires, has driven a significant portion of global warming and air pollution-related deaths. Climate change, in turn, exacerbates drought conditions and creates erratic weather patterns, making forests more susceptible to fires.

To address the issue of wildfires and their impact on air quality, a multifaceted approach is necessary. This includes implementing measures to reduce black carbon emissions, improving land management practices, and increasing investment in planning and prevention. For example, Indonesia is working with local communities to train them in clearing land without using fires and restoring degraded landscapes. Additionally, global initiatives like the Paris Agreement's REDD+ framework aim to protect forests and reduce emissions from deforestation and forest degradation.

As the world continues to grapple with the challenges of climate change, it is crucial to recognize the interconnectedness of these issues. By addressing the root causes of wildfires and implementing sustainable solutions, we can mitigate the air pollution caused by these devastating events and protect both human health and the environment.

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