Home Air Pollution: Causes And Effects Explained

Air pollution is a serious issue that affects people worldwide, and indoor air pollution is a significant contributor to this problem. Household air pollution is mainly caused by the burning of polluting fuels, such as wood, animal dung, charcoal, and kerosene, in open fires or inefficient stoves for cooking, heating, and lighting. Inadequate ventilation, the use of tobacco products, emissions from fireplaces and stoves, cleaning products, building materials, and chemicals stored in the home can all contribute to poor indoor air quality. This can lead to various health issues, including respiratory infections, lung cancer, cardiovascular diseases, and other serious illnesses.

Poor ventilation

One of the main sources of indoor air pollution is tobacco smoke, which contains over 7,000 chemicals, including at least 70 known carcinogens. In addition to tobacco smoke, the use of fireplaces, stoves, cleaning products, paints, and pesticides can release harmful chemicals and emissions into the indoor air. These contaminants can cause various health issues, including eye irritation, coughing, headaches, dizziness, and respiratory infections.

Another issue related to poor ventilation is the buildup of carbon dioxide, which can lead to symptoms such as headaches, dizziness, and fatigue. Furthermore, excessive moisture in poorly ventilated spaces can promote the growth of mould, dust mites, bacteria, and viruses. Mould spores can act as airborne pollutants, triggering allergic reactions and causing respiratory problems, especially in individuals with pre-existing conditions like asthma or allergies.

To address poor ventilation, it is essential to ensure proper airflow and circulation in the home. This can be achieved through the use of fans, opening windows, or installing mechanical ventilation systems. Additionally, addressing moisture issues and regularly cleaning and maintaining HVAC systems can help reduce the presence of biological contaminants. By improving ventilation and eliminating sources of indoor contaminants, the air quality within the home can be significantly enhanced, thereby reducing potential health risks for occupants.

Polluting fuels

Solid fuels such as wood, coal, charcoal, crop waste, and dung are commonly burned for cooking, heating, and lighting in open fires or inefficient stoves. Kerosene, a highly polluting fuel, is also widely used for these purposes. The incomplete combustion of these solid fuels and kerosene releases particulate matter and other pollutants, which can cause inflammation in the airways and lungs, impair immune response, and reduce the oxygen-carrying capacity of the blood.

The use of polluting fuels in the home also poses safety risks beyond the health impacts of indoor air pollution. Kerosene, for example, is often sold in refilled soda bottles, making it a leading cause of childhood poisonings. Open fires and unstable stoves using polluting fuels can result in burns and scalds, especially among children. Additionally, the collection and transportation of heavy loads of fuel can lead to musculoskeletal injuries and chronic pain.

To address the issue of polluting fuels, the WHO has issued guidelines for indoor air quality, specifically targeting household fuel combustion. These guidelines provide evidence-based recommendations on clean fuels and technologies, discouraging the use of kerosene and unprocessed coal. Clean fuels and technologies recommended by the WHO include solar, electricity, biogas, liquefied petroleum gas (LPG), natural gas, alcohol fuels, and biomass stoves that meet emission targets.

It is important to note that the transition to clean fuels and technologies is crucial to reducing household air pollution and protecting the health of those vulnerable to its effects. Policy changes are needed to increase access to clean alternatives, especially in low- and middle-income countries where the burden of household air pollution is often the greatest.

Tobacco smoke

A recent American study found that more than 9 out of 10 children have nicotine residue on their hands, even those whose parents or relatives do not smoke. This is particularly harmful to those who spend the most time at home. Young children exposed to tobacco smoke suffer more from bronchitis, recurrent ear infections, and asthma attacks. Overall, tobacco smoke increases the risk of infections, lung cancer, and chronic lung diseases.

In addition to the immediate health risks, tobacco smoke particles can remain suspended in the air for a while before settling on surfaces, floors, and walls, becoming encrusted in textiles like carpets and curtains. These particles can persist for several months, even years, in closed spaces like cars. They can also react with other compounds in the air to form even more harmful substances, further compromising indoor air quality.

Real-time PM monitoring has been found to be a feasible means of demonstrating tobacco air pollution. For example, in a pilot study involving 29 smoking families, continuous monitoring of PM2.5 levels showed high exposure from smoking in the home. Similarly, the Scottish REFRESH study used 24-hour continuous PM2.5 monitoring, with respondents reporting shock at the high levels resulting from their smoking.

To reduce harm from tobacco smoke, it is important to implement measures such as smoking outdoors, away from windows and doors, and ensuring proper ventilation to dilute and remove indoor contaminants.

Biological contaminants

Bioaerosols, which are airborne particles containing biological contaminants, can be distributed throughout the home via HVAC systems. They can cause infectious diseases like Legionnaires' disease and allergic reactions, including hypersensitivity pneumonitis, allergic rhinitis, and certain types of asthma. Symptoms associated with biological pollutants include sneezing, eye irritation, coughing, dizziness, and respiratory infections.

Poor ventilation exacerbates the presence of biological contaminants. Inadequate ventilation can lead to a buildup of contaminants and carbon dioxide, resulting in health issues such as headaches, dizziness, and fatigue. This is particularly relevant in homes that are tightly sealed to conserve energy, as outdoor air cannot enter to dilute the contaminants.

Additionally, biological contaminants can be introduced into the home through various means. Outdoor allergens, such as pollen, mould, and pet dander, can be carried indoors on clothing, shoes, and pets. Construction processes and products, like carpets and paints, can also introduce biological contaminants into indoor air.

To mitigate the impact of biological contaminants, it is essential to maintain proper ventilation and address sources of moisture to prevent the growth of mould and the proliferation of other biological pollutants.

Cleaning products

The fragrances added to cleaning products can increase the likelihood of respiratory irritation. Antibacterial cleaning products may also pose a risk of antibiotic resistance, despite their benefits in preventing gastrointestinal or bacterial infections like salmonella. Furthermore, cleaning products can generate small SOAs (with a diameter of 10 nanometres or less), which can expose the lungs to similar pollutant particle levels as spending time by a busy road.

To mitigate the impact of cleaning products on indoor air quality, it is recommended to opt for green or natural products, which do not contain synthetic chemicals. These "green products" have been found to be less harmful than conventional cleaning products, although more research is needed to understand their effects on respiratory health. Additionally, ensuring proper ventilation and using fans with filters can help reduce the concentration of indoor air pollutants.

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