Air Pollution's Health Hazards: The Indoor Story

Indoor air pollution is a serious threat to human health, causing millions of deaths each year. The World Health Organization (WHO) estimates that indoor air pollution was responsible for 3.2 million deaths per year in 2020, including over 237,000 children under the age of five. The main sources of indoor air pollution include cooking, smoking, use of electronic machines, consumer products, and emission from building materials. These sources release harmful pollutants such as carbon monoxide, volatile organic compounds, particulate matter, aerosol, and biological pollutants.

The health effects of indoor air pollution are widespread and can affect almost every organ in the body. Due to their small size, some air pollutants can penetrate deep into the lungs and enter the bloodstream, leading to systemic inflammation and carcinogenicity. Short-term exposure to indoor air pollution can cause respiratory infections, trigger asthma attacks, and aggravate lung diseases. Long-term exposure has been linked to an increased risk of stroke, ischaemic heart disease, chronic obstructive pulmonary disease, lung cancer, and other serious health issues.

It is important to address indoor air pollution to protect human health and reduce the burden of disease associated with it. Strategies to improve indoor air quality include ensuring proper ventilation, using natural and energy-efficient building materials, choosing green and natural cleaning products, and utilizing air purifiers and indoor plants. By implementing these measures, we can reduce our exposure to indoor air pollutants and mitigate their negative impact on our health.

Indoor air pollution can cause respiratory issues, including coughing, asthma, and lung disease

Indoor air pollution can have a detrimental impact on human health, and is a pressing issue worldwide. It can cause and exacerbate a range of respiratory issues, including coughing, asthma, and lung disease.

Coughing is a reflex action to clear the throat of mucus or foreign substances. While not a serious health issue in itself, a persistent cough can indicate a more serious underlying condition. Long-term exposure to indoor air pollution can cause chronic coughing, which may then lead to more serious respiratory issues.

Asthma is a chronic respiratory disease characterised by sudden attacks of breathlessness and wheezing, which can be triggered by exposure to air pollutants. People with asthma are particularly vulnerable to indoor air pollution, especially nitrogen dioxide (NO2) and sulfur dioxide (SO2). Exposure to these pollutants can lead to increased hospitalisations, more frequent use of rescue inhalers, and reduced response to asthma treatments.

Indoor air pollution can also cause and aggravate lung diseases such as chronic obstructive pulmonary disease (COPD) and lung cancer. COPD is an inflammatory response in the airways and lungs to harmful particles or gases. Air pollution, particularly particulate matter, can cause inflammation in the lungs and further impair pulmonary function in COPD patients. Lung cancer is also associated with indoor air pollution, especially from the use of solid fuels such as biomass or coal for cooking and heating.

To reduce the health risks associated with indoor air pollution, it is essential to improve indoor air quality. This can be achieved by using clean fuels, improving ventilation, and utilising air filtration systems. Additionally, wearing masks, especially those with an N95 rating, can help reduce exposure to indoor air pollutants.

It can also lead to cardiovascular issues, such as heart disease and stroke

Indoor air pollution can lead to cardiovascular issues, such as heart disease and stroke. The American Heart Association recognises air pollution as a risk factor for heart disease, with someone dying from cardiovascular disease every 40 seconds in the United States.

Particulate matter (PM) in the air, especially PM2.5, is a major cause of cardiovascular issues. PM2.5 is particulate matter with a diameter of less than 2.5 micrometres, which can be inhaled and penetrate deep into the respiratory tract, affecting the heart and lungs. Sources of PM2.5 include power plants, factories, automobiles, and wildfire smoke.

Research has found that exposure to increased concentrations of PM2.5 over a few hours to weeks can trigger cardiovascular issues, including heart attacks. Longer-term exposure can lead to an increased risk of cardiovascular mortality and decreased life expectancy. For example, a study found that for every 10 μg/m3 increase in PM2.5, there was a corresponding 0.7% increase in cardiopulmonary mortality. Another study found that a 10.5 μg/m3 increase in PM2.5 levels was associated with a 2.8 mmHg increase in systolic blood pressure and a 2.7 mmHg increase in diastolic blood pressure in patients over five days.

In addition to PM2.5, other air pollutants such as nitrogen dioxide (NO2) and sulfur dioxide (SO2) have also been linked to cardiovascular issues. For instance, NO2 has been positively associated with cardiovascular morbidity, hospitalization, and mortality, especially in patients with cardiovascular diseases aged 65 years or older.

Overall, indoor air pollution, particularly fine particulate matter, has been shown to have significant adverse effects on cardiovascular health, leading to issues such as heart disease and stroke.

Indoor air pollution has been linked to an increased risk of cancer, particularly lung cancer

The sources of indoor air pollution include inefficient and polluting fuels and technologies used in and around the home, such as open fires or inefficient stoves fuelled by kerosene, biomass (wood, animal dung, and crop waste), and coal. These sources contain a range of health-damaging pollutants, including small particles that penetrate deep into the lungs and enter the bloodstream. In poorly ventilated dwellings, indoor smoke can have levels of fine particles 100 times higher than acceptable levels. Exposure is particularly high among women and children, who spend the most time near the domestic hearth.

The effects of indoor air pollution on health include:

• Lung cancer: Approximately 11% of lung cancer deaths in adults are attributable to exposure to carcinogens from household air pollution caused by using kerosene or solid fuels like wood, charcoal, or coal for household energy needs.
• Respiratory diseases: Indoor air pollution increases the risk of acute lower respiratory infections, particularly in children under 5 years old. It also contributes to acute lower respiratory infections in adults and is responsible for 22% of all adult deaths due to pneumonia.
• Cardiovascular diseases: Indoor air pollution increases the risk of ischaemic heart disease and stroke.
• Other health issues: Indoor air pollution can cause or worsen coughing, itchy eyes, and breathing problems, leading to hospitalizations. It can also trigger asthma attacks or cause wheezing.

It can cause eye and throat irritation, headaches, and other adverse effects

Indoor air pollution can cause eye and throat irritation, headaches, and other adverse effects. The eye is a delicate organ with a large surface area exposed to the environment, making it vulnerable to harm from air pollution. Airborne particles and chemicals, such as dust, nitrogen dioxide, and volatile organic compounds, can cause eye irritation, leading to symptoms like itching, burning, and redness. Similarly, pollutants can irritate the throat and nose, causing a burning sensation.

Indoor air pollution can also trigger headaches. Carbon monoxide, an odorless and colorless gas, is a common indoor pollutant that can induce headaches, along with nausea, dizziness, and even death in extreme cases. Prolonged exposure to indoor air pollution may also lead to more severe issues, including respiratory illnesses, allergies, and other serious health conditions.

Additionally, indoor air pollution can exacerbate existing allergies, causing symptoms such as watery eyes and sneezing. Biological contaminants, including pests, pet dander, dust mites, and mold, are common sources of indoor biological pollutants that can trigger allergic reactions and respiratory problems.

To protect against indoor air pollution, it is essential to identify and address all potential sources of pollution. Strategies such as improving ventilation, using air purifiers, and reducing the use of pollutants can help minimize indoor air pollution and its adverse effects on human health.

Prolonged exposure to indoor air pollution can result in serious health issues and even premature death

Indoor air pollution is a serious health threat, causing millions of deaths each year. It is caused by a plethora of pollutants, which can be categorised into organic, inorganic, biological, or radioactive. Common indoor air pollutants include radon, smoke, and lead dust. Carbon monoxide from a faulty furnace, mould from damp walls, or volatile organic compounds from a newly painted room also contaminate indoor air.

The World Health Organization (WHO) states that indoor air pollution is responsible for the deaths of 3.8 million people annually. The combined effects of ambient air pollution and indoor air pollution are associated with 6.7 million premature deaths annually. In 2020, indoor air pollution was responsible for an estimated 3.2 million deaths per year, including over 237,000 deaths of children under the age of five.

Indoor air pollution exposure leads to non-communicable diseases, including stroke, ischaemic heart disease, chronic obstructive pulmonary disease (COPD), and lung cancer. Other diseases associated with indoor air pollution include pneumonia, cataracts, tuberculosis, low birth weight, and nasopharyngeal and laryngeal cancers.

Indoor air pollution can also cause building-associated illnesses, including sick building syndrome (SBS) and building-related illness (BRI). SBS refers to a group of symptoms that are linked to the physical environment of specific buildings. BRI describes illnesses and symptoms with a causative agent directly related to exposure to poor air quality in buildings.

Indoor air pollution can also cause acute respiratory infections, which can be classified into acute lower respiratory infections (ALRIs) and upper respiratory infections (URIs). ALRIs are acute infections of the lung, caused by viruses or bacteria, resulting in lung inflammation. URIs involve the upper respiratory system and are often mild in nature, caused by biological pollutants such as viruses, bacteria, fungi, fungal spores, and mites.

Indoor air pollution is also linked to pulmonary diseases, such as asthma, atopic dermatitis, and allergic rhinitis. Smoking is one of the most important factors in the development of chronic inflammatory pulmonary diseases, including COPD, asthma, and lung cancer. Exposure to indoor air pollutants can result in asthma symptoms or cause asthma exacerbations.

Indoor air pollution is a significant contributing cause of human diseases. Most people spend around 90% of their time indoors, mainly at home or in the workplace, and are therefore exposed to indoor air pollutants for long periods of time. Prolonged exposure to indoor air pollution can result in serious health issues and even premature death.

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