Asthma And Air Pollution: What's The Worst Offender?

Asthma is a chronic respiratory disease that affects over 23 million Americans, causing variable airflow obstruction, bronchial hyperresponsiveness, and airway inflammation. Air pollution is a significant trigger for asthma attacks, and people with asthma are at greater risk from breathing in small particles and irritating gases found in air pollution. This paragraph will explore which form of air pollution aggravates asthma the most.

Outdoor air pollution: ozone, particulate matter, and nitrogen dioxide

Outdoor air pollution, including ozone, particulate matter, and nitrogen dioxide, can aggravate asthma. These pollutants can irritate the airways, causing them to swell and tighten, making it difficult to breathe. People with asthma are particularly vulnerable to the effects of air pollution, and their exposure to it can worsen their symptoms and trigger asthma attacks.

Ozone is a gas that is beneficial in the upper atmosphere but becomes harmful when found in the air we breathe at ground level. Ground-level ozone is formed when chemicals from cars, power plants, and factories mix with sunlight. It is a major component of smog, which is often seen as a brownish-yellow haze over cities. Ground-level ozone pollution is more prevalent in warmer climates or during warmer seasons.

Particulate matter (PM) refers to small airborne particles found in haze, smoke, soot, and dust. The smallest particles, known as PM2.5, pose the greatest danger as they can penetrate deep into the lungs and even enter the bloodstream. PM2.5 has been linked to increased cases of childhood asthma and more frequent and severe asthma attacks.

Nitrogen dioxide (NO2) is another significant outdoor air pollutant that can worsen asthma symptoms. It is commonly produced by vehicles, power plants, and industrial facilities. Exposure to NO2 can irritate the airways and lungs, exacerbating respiratory issues in people with asthma.

It is important for individuals with asthma to be aware of pollution levels, especially when outdoor air pollution is high. Taking precautions, such as limiting time outdoors, increasing medication, and staying in well-ventilated or air-conditioned spaces, can help manage asthma symptoms during periods of high air pollution.

While outdoor air pollution is a concern, it is worth noting that indoor air pollution can also aggravate asthma. Sources of indoor air pollution include allergens, volatile organic compounds (VOCs), cooking, and the use of unflued gas heaters, which can emit nitrogen dioxide and carbon monoxide.

Indoor air pollution: carbon monoxide, nitrogen dioxide, and formaldehyde

Air pollution can increase the risk of developing asthma and worsen symptoms for those already suffering from the condition. People with asthma are at greater risk from breathing in small particles and irritating gases, which can irritate the airways. Outdoor air pollution comes from both manmade and natural sources, while indoor air pollution can come from various sources, such as allergens, volatile organic compounds (VOCs), and damaging gases like carbon monoxide.

Carbon monoxide (CO) forms from the incomplete combustion of fuels and wood. It has no smell and can be dangerous when it builds up inside buildings, homes, and cars. Studies have shown that carbon monoxide levels in exhaled air are increased in asthmatic patients. However, it is uncertain whether exhaled CO is related to the severity of asthma.

Nitrogen dioxide (NO2) is another indoor air pollutant that damages the human respiratory system and contributes to acid rain. It is formed from emissions from vehicles, power plants, and other industrial sources. Breathing in NO2 can worsen lung disease, especially asthma.

Formaldehyde is a well-known airborne contaminant that can irritate the eyes, nose, throat, and airways and cause slight neuropsychological changes. It is released from various indoor sources, including off-gassing from urea-formaldehyde foam insulation, particleboard, paneling, plywood, some carpets and furniture, tobacco smoke, and indoor combustion sources. While formaldehyde exposure has been linked to occupational asthma, it is still debated whether non-occupational exposure is a risk factor for developing asthma. Some studies suggest that exposure to formaldehyde may lead to exacerbation of asthma symptoms, while others found no significant deleterious effects on airway allergen responsiveness in patients with intermittent asthma.

In summary, indoor air pollution, including carbon monoxide, nitrogen dioxide, and formaldehyde, can aggravate asthma symptoms and increase the risk of developing asthma. It is important for individuals with asthma to limit their exposure to indoor air pollutants and take precautions to improve indoor air quality, such as increasing ventilation and avoiding known sources of indoor pollutants.

Children are vulnerable: gene alterations, respiratory changes, and infections

Air pollution poses severe risks to children's health, causing respiratory infections, asthma, cognitive developmental issues, and lifelong health issues. It was the second leading risk factor for death among children under five in 2021, after malnutrition. It is linked to gene alterations, respiratory changes, and infections in children.

Gene Alterations

Air pollution exposure is linked to methylation of immunoregulatory genes, altered immune cell profiles, and increased blood pressure in children. Exposure to fine particulate matter (PM2.5), carbon monoxide (CO), and ozone (O3) is linked to altered methylation of most CpG sites for genes Foxp3, IL-4, IL-10, and IFN-g, all involved in immune regulation.

Respiratory Changes

Air pollution exposure is associated with respiratory changes in children. Short-term exposures to O3, PM10, and PM2.5 are associated with lower lung function indices. Studies support the association between early-life or long-term air pollutant exposure and decreased lung function. Prenatal exposure to air pollution may be associated with an increased risk of adverse respiratory outcomes during childhood. Disruptions to the lungs' functional growth and repair mechanisms can render them more susceptible to acute respiratory infections and asthma during childhood.

Infections

Air pollution exposure is linked to an increased risk of respiratory infections in children. Various physiological, cultural, and behavioural factors increase children's susceptibility to adverse health outcomes from air pollution. Behavioural factors include breastfeeding mothers or mothers carrying children on their backs or laps while cooking indoors, inadvertently exposing them to high degrees of household air pollution (HAP). Air pollution is strongly associated with pneumonia, which accounts for 22% of all deaths of children between one and five years of age. Ground-level ozone is a powerful airway irritant and can cause breathing problems, especially in children with asthma.

Children are vulnerable to the effects of air pollution, and it is crucial to understand the multifaceted impacts on their health to provide early clues for clinical intervention and reduce the health burden associated with diseases such as asthma.

At-risk groups: people near pollution sources and African American adolescents

Air pollution is a major risk factor for asthma, and certain groups are more vulnerable to its harmful effects than others. One of the most vulnerable groups is people who live near sources of pollution, such as busy roadways, power plants, industrial facilities, and oil and gas production sites. These individuals are exposed to high levels of air pollutants, including particulate matter (PM), ozone, nitrogen dioxide (NO2), and volatile organic compounds (VOCs).

Particulate matter, or PM, refers to small airborne particles found in haze, smoke, soot, and dust. The smallest particles, known as PM2.5, can penetrate deep into the lungs and even enter the bloodstream, causing serious health issues. People living near pollution sources are at an increased risk of inhaling these harmful particles, which can irritate the airways and trigger asthma attacks.

Another group that is particularly at risk from air pollution includes African American adolescents. Research has shown that African American youth have a higher likelihood of being diagnosed with asthma compared to other ethnic groups, and this risk increases with a decrease in socioeconomic status. They also experience higher rates of emergency department visits and hospitalizations for asthma-related issues. Additionally, African American children with moderate-to-severe persistent asthma are more vulnerable to the effects of air pollution, even at low levels of outdoor ozone.

The reasons for the increased vulnerability of African American adolescents are multifaceted. One factor is the lack of adequate health insurance, which creates barriers to proper diagnosis and treatment. Additionally, indoor allergen levels, such as exposure to cockroaches and secondhand tobacco smoke, are higher in urban households with low incomes, further exacerbating asthma symptoms. Long-term maternal stress and exposure to stress and violence in early life have also been associated with an increased risk of childhood asthma in this demographic.

Overall, it is clear that people living near pollution sources and African American adolescents are at a heightened risk of experiencing asthma-related health issues due to air pollution. These groups require targeted interventions and strategies to mitigate the impact of air pollution on their respiratory health and overall well-being.

Precautions: limiting outdoor time, increasing medicine, and air conditioning

Air pollution is associated with the development and worsening of asthma. It can irritate the airways and cause oxidative injury, inflammation, remodelling, and increased risk of sensitisation. While air pollution is a broad issue, there are specific pollutants that are particularly harmful to people with asthma. These include nitrogen dioxide (NO2), ozone, sulphur dioxide, and particulate matter (PM), especially PM2.5, which is small enough to enter the lungs and bloodstream.

Precautions

Limiting outdoor time

When air pollution levels are high, people with asthma should limit their time outdoors, especially between 11 am and 8 pm. It is important to avoid outdoor exercise or strenuous work during these periods as well.

Increasing medicine

While not directly mentioned in the sources, it is implied that people with asthma should follow their asthma action plan and use their medication as prescribed. This may include the use of rescue inhalers during periods of high air pollution.

Air conditioning

Air conditioning is recommended for people with asthma, as it can help maintain a pleasant temperature and purify the air of harmful substances. It is important to ensure that the air conditioning system is maintained properly and that the indoor and outdoor temperature difference does not exceed five to eight degrees. Additionally, ideal humidity levels should be maintained between 40% and 60%, as both dry and humid environments can worsen asthma symptoms.

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