Air Pollution: Harmful Effects On Your Body

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, causing more than 6.5 million deaths each year. Air pollution can affect almost every organ in the body, and breathing in these pollutants can lead to inflammation, oxidative stress, immunosuppression, and mutagenicity in cells throughout the body, impacting the lungs, heart, and brain, among other organs, and ultimately leading to disease. Some of the most common air pollutants leading to disease include particulate matter (PM), carbon monoxide (CO), ozone (O3), nitrogen dioxide (NO2), and sulphur dioxide (SO2). These pollutants can cause a variety of health issues, including coughing, itchy eyes, and respiratory and cardiovascular problems. Certain groups, such as children, the elderly, and people with pre-existing health conditions, may be more vulnerable to the effects of air pollution.

Air pollution increases the risk of lung cancer and strokes

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 more than 6.5 million deaths each year globally. Vehicle emissions, fuel oils, natural gas, and fumes from chemical production are the primary sources of human-made air pollution. Nature also releases hazardous substances into the air, such as smoke from wildfires, ash and gases from volcanic eruptions, and methane emitted from decomposing organic matter in soils.

Air pollution is linked to an increased risk of lung cancer. Fine particulate matter, or PM2.5, from agriculture and wildfires has been specifically associated with an increased risk of lung cancer. PM2.5 is 30 times thinner than a human hair and can be inhaled deeply into lung tissue, contributing to serious health problems. It can cause local inflammation and oxidative stress, and even penetrate deep into the lungs and terminal bronchioles, entering the circulation and causing systemic inflammation. This can increase the risk of lung cancer through inflammatory damage, reactive oxygen species production, and oxidative DNA damage.

In addition to lung cancer, air pollution has been identified as a risk factor for many cardiovascular diseases (CVD), including stroke. Exposure to urban PM has been shown to cause pulmonary inflammation and elevated levels of inflammatory markers in the blood. This can lead to a decrease in the availability of NO, a key regulator of vascular tone and blood pressure. As a result, individuals with pre-existing cardiorespiratory diseases are particularly vulnerable to the adverse cardiovascular risks posed by air pollution.

While the relative risk of stroke at an individual level is small, the ubiquitous nature of exposure to air pollution means that the absolute risk at a population level is significant. This is particularly concerning in low and middle-income countries, where air pollution is projected to rise due to rapid industrialization. The association between air pollution and stroke is well-established, with epidemiological studies demonstrating that both short- and long-term exposure to air pollution increases the risk of stroke.

It can lead to systemic inflammation and carcinogenicity

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, causing more than 6.5 million deaths each year. Almost every organ in the body can be impacted by air pollution.

Fine particulate matter (PM 2.5) is a major source of air pollution. These particles are 30 times thinner than a human hair and can be inhaled deeply into lung tissue, causing serious health problems. PM 2.5 accounts for most health effects due to air pollution. These particles can enter the bloodstream and travel to organs, causing systemic damages to tissues and cells.

Long-term exposure to air pollution can lead to systemic inflammation. Studies have shown higher levels of inflammatory molecules circulating in the blood of people with long-term exposure to different kinds of air pollution. This exposure impairs the immune system's ability to regulate inflammation, leading to other serious health conditions. For example, people with chronic exposure to air pollution may experience a dysregulated immune response when presented with a threat, leading to potential heart and lung diseases.

Air pollution has also been classified as a human carcinogen, particularly for lung cancer. Particulate matter in outdoor air has been linked to lung cancer incidence and mortality. Studies have shown that changes in airway cells due to exposure to particle pollution are visible in about half of people with lung cancer who have never smoked. In addition to lung cancer, air pollution has been associated with an increased risk of other types of cancer, such as bladder and breast cancer.

It can cause or worsen lung diseases, including asthma

Air pollution can cause or worsen lung diseases, including asthma. The small particles in polluted air can irritate the lungs and airways, making it harder to breathe and triggering asthma attacks. Ozone, a common air pollutant, is particularly harmful when found closer to the ground in the air we breathe. Ground-level ozone is created when chemicals from cars, power plants, and factories mix with sunlight. It is most common in cities during the summer when there is more sunlight, heat, and low wind.

Ozone is an irritant that can trigger asthma attacks by irritating the lungs and airways. Nitrogen dioxide (NO2) is another pollutant that can induce coughing, wheezing, and even pulmonary edema when inhaled at high levels. Breathing in NO2 can also cause someone to develop asthma. Sulfur dioxide (SO2) is a pollutant that comes from burning fossil fuels, transportation, and industrial processes. It can harm the lungs and lead to health problems. Carbon monoxide (CO) is a dangerous, colorless and odorless gas that can build up inside buildings, homes, and cars. It forms from the incomplete combustion of fuels and wood.

Particulate matter (PM) is a complex mixture of dirt, soot, smoke, and liquid droplets from both natural and man-made sources. PM2.5, a subset of PM, is 30 times thinner than a human hair and can be inhaled deeply into lung tissue, increasing the frequency and severity of asthma attacks. Sources of PM include wind-blown dust, volcanic ash, pollen, and fungal spores, among others. The smaller the particles, the deeper they can penetrate into the lungs, causing breathing problems.

Biological pollutants, such as mold, pollen, animal dander, and dust mites, can also trigger asthma attacks by irritating the airways and making them swell and tighten up. These pollutants can also make children more susceptible to upper respiratory infections, which can bring on asthma symptoms.

It can cause shortness of breath, coughing, and wheezing

Air pollution can cause a range of respiratory issues, including shortness of breath, coughing, and wheezing. The main pathway of exposure to air pollution is through the respiratory tract. When we breathe in air pollutants, they can enter our bloodstream and contribute to coughing or itchy eyes. They can also cause or worsen many breathing and lung diseases, leading to hospitalizations, cancer, or even premature death.

People with pre-existing respiratory conditions, such as asthma or chronic obstructive pulmonary disease (COPD), are particularly vulnerable to the effects of air pollution. For these individuals, air pollution can make it harder to breathe, trigger asthma attacks, and cause wheezing and coughing. Even in low concentrations, air pollution can affect people's respiratory health and cause shortness of breath.

Air pollution is a mix of hazardous substances from both human-made and natural sources. Vehicle emissions, fuel oils, natural gas used for heating, and fumes from chemical production are significant human-made sources of air pollution. Meanwhile, nature releases hazardous substances such as smoke from wildfires, ash and gases from volcanic eruptions, and methane from decomposing organic matter.

The size of the particles in the air pollution we inhale is a critical factor in the damage they can cause. Particles with a diameter of 10 microns or less can penetrate and lodge deep inside the lungs, causing irritation and inflammation and damaging the lining of the respiratory tract. Smaller particles, with a diameter of 2.5 microns or less, can penetrate the lung barrier and enter the bloodstream, affecting all major organs of the body. These smaller particles are known as PM2.5 and are responsible for most health effects due to air pollution in the United States. They are 30 times thinner than a human hair and can be inhaled deeply into the lung tissue, contributing to serious health problems.

Ozone (O3) is another significant pollutant that can irritate the lungs and cause inflammation. It is often called smog when found at ground level and is created when pollutants from cars, power plants, and other sources react chemically in the presence of sunlight.

Air pollution has been linked to an increased risk of dementia

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, causing more than 6.5 million deaths each year worldwide. This number has increased over the past two decades.

Air pollution is the presence of one or more contaminants in the atmosphere, such as dust, fumes, gas, mist, odour, smoke, or vapour, in quantities that can be harmful to human health. The main pathway of exposure is through the respiratory tract, but some pollutants can also enter the body through the bloodstream or the skin. Almost every organ in the body can be impacted by air pollution, including the lungs, heart, and brain.

Fine particulate matter (PM2.5) is a subset of PM that is 30 times thinner than a human hair. It can be inhaled deeply into lung tissue and contribute to serious health problems. PM2.5 accounts for most health effects due to air pollution in the US.

A growing body of evidence suggests that exposure to air pollution is linked to an increased risk of dementia. While the exact mechanism is not yet fully understood, researchers have found that fine particulate matter can enter the lungs, circulate in the blood, and move into the brain, where they may cause direct damage.

A 2023 study by Boya Zhang and Sara Adar from the University of Michigan examined the links between different types of PM2.5 air pollution and dementia. They analysed data from over 27,000 adults aged 50 and older and found that higher PM2.5 exposure was associated with an increased risk of dementia. Specifically, PM2.5 from agriculture and wildfires was linked to a higher number of dementia cases.

In addition, people from low-income communities and minority populations are disproportionately exposed to air pollution and are more vulnerable to adverse health impacts, including dementia.

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