Air Pollution: Understanding The Toxic Air We Breathe

Air pollution is a significant environmental health hazard that affects both indoor and outdoor environments. It refers to the presence of harmful substances in the air, such as gases, solid and liquid particles, and biological agents. These pollutants are released into the atmosphere through human activities, natural sources, or a combination of both. The burning of fossil fuels, vehicle emissions, industrial processes, and agricultural practices are major contributors to air pollution. The health impacts of air pollution are widespread, ranging from respiratory and cardiovascular issues to an increased risk of cancer and premature death. Addressing air pollution through regulations, sustainable practices, and cleaner technologies is crucial for protecting public health and mitigating its detrimental effects on the planet.

Health risks

Air pollution is a mix of hazardous substances from both human-made and natural sources. It is a major threat to global health and prosperity and is the fourth-largest risk factor for early death worldwide. According to the World Health Organization (WHO), air pollution is responsible for nearly seven million deaths globally each year.

Air pollution exposure is associated with oxidative stress and inflammation in human cells, which may lay the foundation for chronic diseases and cancer. The International Agency for Research on Cancer of the World Health Organization (WHO) has classified air pollution as a human carcinogen. Short-term exposure to higher levels of outdoor air pollution is associated with reduced lung function, asthma, cardiac problems, emergency department visits, and hospital admissions. Long-term exposure to fine particulate matter increases a person's risk of noncommunicable diseases, including stroke, heart disease, chronic obstructive pulmonary disease, and cancer.

Fine particulate matter, such as soot, is made up of tiny particles of chemicals, soil, smoke, dust, or allergens that are carried in the air. These particles can penetrate deep into the lungs and enter the bloodstream, causing systemic damage to tissues and cells. Exposure to high levels of particulate matter can lead to reduced lung function, respiratory infections, and aggravated asthma.

Smog, or ground-level ozone, occurs when emissions from combusting fossil fuels react with sunlight. Smog can irritate the eyes and throat and damage the lungs, especially in children, senior citizens, and people who work or exercise outdoors. It can also intensify asthma and allergy symptoms and trigger asthma attacks.

Air pollution is also associated with adverse pregnancy outcomes, such as low birth weight and small gestational age. Research has shown that living near major roadways may increase a woman's risk for breast cancer. Additionally, exposure to air pollution during pregnancy can increase the risk for dangerous changes in blood pressure, known as hypertensive disorders, which are a leading cause of preterm birth, low birth weight, and maternal and fetal illness and death.

Children are particularly vulnerable to the health risks of air pollution. Higher levels of air pollution increase short-term respiratory infections, leading to more school absences. Children who play outdoor sports and live in high-ozone communities are more likely to develop asthma. Living in communities with higher pollution levels can cause lung damage and increase the risk of cognitive and emotional problems later in adolescence.

Furthermore, air pollution disproportionately affects people of color and low-income communities. People of color are more likely to live with chronic conditions that make them more susceptible to the health impacts of air pollution, including asthma and diabetes. Low-income areas often have higher pollution levels, and residents have fewer resources to relocate or access quality healthcare, making them more vulnerable to pollution-related health effects.

Natural sources

Air pollution is the contamination of the indoor or outdoor environment by any chemical, physical, or biological agent that modifies the natural characteristics of the atmosphere. While most air pollution is caused by human activity, natural sources can also contribute to air pollution. Natural sources of air pollution include:

Wildfires

Wildfires are a significant natural source of air pollution, releasing smoke and particulate matter into the atmosphere. They are a major source of outdoor carbon monoxide (CO) and contribute to the formation of smog, which can irritate the eyes and throat and damage the lungs. Wildfires are also associated with increased rates of dementia.

Volcanic Eruptions

Volcanic eruptions release ash and gases into the atmosphere, which can have both local and global impacts on air quality. Volcanic emissions can include hazardous substances such as sulfur dioxide, hydrogen sulfide, and carbon dioxide.

Dust Storms

Dust storms occur when strong winds lift large amounts of sand and dust into the air, reducing visibility and affecting air quality. These storms are a significant source of particulate matter, which can have adverse health effects, especially in urban areas.

Radon Gas

Radon gas is a naturally occurring radioactive gas released through the surface of the Earth. It can accumulate in homes and other buildings, posing a health risk as it is a known carcinogen. Radon gas is colourless and odourless, making it difficult to detect without proper equipment.

Sea Spray

Sea spray refers to the aerosol particles produced by the breaking of ocean waves. While it is a natural source of particulate matter, it typically contributes less to air pollution than human-made sources.

It is important to note that while natural sources of air pollution exist, human activities, such as burning fossil fuels, industrial processes, and vehicle emissions, remain the predominant contributors to global air pollution.

Human-made sources

Air pollution is the contamination of the indoor or outdoor environment by any physical, chemical, or biological agent that modifies the natural characteristics of the atmosphere. Human activities are a major contributor to air pollution, with the burning of fossil fuels being a primary source.

Vehicles

Vehicle emissions, including exhaust fumes and tailpipe emissions, are a significant source of air pollution. This includes cars, trucks, airplanes, and other vehicles that burn fossil fuels such as gasoline, diesel, or natural gas. These emissions release pollutants such as nitrogen oxides, particulate matter, and carbon monoxide into the atmosphere.

Industrial Processes

Factories, power plants, and industrial facilities contribute to air pollution through the burning of fossil fuels, especially coal, oil, and natural gas. These processes release pollutants such as nitrogen oxides, sulfur oxides, and carbon monoxide. Industrial processes such as oil and gas development and drilling are also significant sources of methane emissions.

Residential Energy Use

Residential energy use for cooking, heating, and electricity generation can contribute to air pollution. The burning of fossil fuels, such as gasoline, oil, or fracked gas for these purposes releases harmful chemicals and gases into the air.

Agriculture and Waste Incineration

Agricultural processes, including coal mines, waste management, and the use of biomass, contribute to air pollution. Methane emissions are common in agricultural processes, while waste incineration releases pollutants into the air.

Construction and Manufacturing

Construction and manufacturing sectors are also major sources of air pollution. This includes emissions from construction sites, as well as the use of fossil fuels and industrial processes in manufacturing. A 2014 study found that these sectors contributed more than 50% of air pollution in China.

Tobacco Smoke

Tobacco smoke, including cigarette and e-cigarette smoke, is considered a source of indoor and outdoor air pollution. Secondhand smoke can increase the risk of lung cancer, and smoking can also lead to the spread of toxic mould.

Air quality laws

Air pollution is a mix of hazardous substances from both human-made and natural sources. It is a major threat to global health and prosperity and is responsible for millions of deaths each year. The World Health Organization (WHO) has developed and implemented a strategy to raise awareness about the risks of air pollution and the solutions to mitigate them.

In the United States, the Clean Air Act (CAA), established in 1970, authorises the U.S. Environmental Protection Agency (EPA) to regulate the emissions of harmful air pollutants and safeguard public health. The Act mandates controls on air pollution from mobile sources by regulating the composition of fuels and emission-control components on motor vehicles and non-road engines. The EPA is also responsible for setting National Ambient Air Quality Standards (NAAQS) to protect public health and welfare. The Act was amended in 1977 and 1990 to set new goals for achieving NAAQS, as many areas had failed to meet the initial deadlines.

Section 112 of the Clean Air Act addresses emissions of hazardous air pollutants. The 1990 amendments revised this section to require the issuance of technology-based standards for "major sources" and certain "area sources". The EPA is required to establish emission standards, commonly referred to as "maximum achievable control technology" or "MACT" standards, for major sources to ensure the maximum degree of reduction in hazardous air pollutant emissions.

The EPA also provides information about greenhouse gas emissions, including emission levels, sources, and options for cutting emissions. While the EPA does not regulate indoor air, it offers assistance in protecting indoor air quality and provides guidelines for mould remediation in schools and commercial buildings. Additionally, the EPA is the primary federal agency responsible for protecting people and the environment from harmful radiation exposure.

Individual states or tribes may have stronger air pollution laws than the CAA, but they cannot set pollution limits weaker than those established by the EPA. For example, the California Air Resources Board (CARB) is authorised to set ambient air quality standards for the state. The Office of Air and Radiation (OAR) within the EPA develops national programs, policies, and regulations for controlling air pollution and radiation exposure.

Strategies to reduce air pollution

Air pollution is a mix of hazardous substances from both human-made and natural sources. Human-made air pollution comes from vehicle emissions, fuel oils, natural gas, manufacturing by-products, and power generation. Natural sources include smoke from wildfires, ash and gases from volcanic eruptions, and gases from decomposing organic matter.

Reduce Vehicle Emissions

Vehicle emissions are a major source of air pollution. To reduce emissions from vehicles, individuals can opt for more fuel-efficient cars, carpool, or use shared taxi services. Additionally, individuals can choose to walk, cycle, or use public transportation instead of driving whenever possible. Governments can also implement policies to encourage active transportation and reduce the number of vehicles on the road, such as creating dedicated bicycle lanes and carpool lanes.

Improve Energy Sources

The burning of fossil fuels, such as coal, gasoline, and natural gas, releases harmful pollutants into the air. To reduce air pollution, individuals can switch to cleaner energy sources, such as solar power. Governments can also provide incentives and subsidies to make cleaner energy sources more accessible and affordable for the public.

Proper Waste Management

The burning of waste, such as leaves, old tires, or trash, releases toxic pollutants into the air. Individuals should avoid open burning and properly dispose of waste through recycling or municipal waste management systems. Governments can implement laws and fines to punish those who illegally burn waste and encourage the use of alternative waste disposal methods, such as composting.

Plant and Care for Trees

Trees are natural air filters that absorb carbon dioxide and release oxygen into the atmosphere. Individuals can contribute by planting and caring for trees in their communities. Governments can also initiate tree-planting programs and create green spaces in urban areas to help improve air quality.

Reduce Gas Consumption

Gas consumption, such as using gasoline for cars or natural gas for heating, contributes to air pollution. Individuals can reduce their gas consumption by planning ahead and consolidating errands to reduce the number of miles driven. Additionally, properly maintaining vehicles and keeping tires inflated to the suggested amount can improve fuel efficiency and reduce emissions.

Frequently asked questions