Indoor Air Pollution: Who Suffers The Most?

Indoor air pollution is a serious issue, causing approximately 3.2 million deaths worldwide each year, according to the World Health Organization. It is especially harmful as people spend approximately 90% of their time indoors. The young, the elderly, and those with chronic illnesses are most susceptible to the effects of indoor air pollution.

Indoor air pollution is caused by a variety of sources, including inadequate ventilation, mould growth, HVAC systems, cleaning products, and building materials. Poor ventilation is a common issue, as it prevents emissions from being diluted and allows pollutants to accumulate. Tobacco smoke, cooking stoves, cleaning products, and pet dander are also significant contributors to indoor air pollution.

The effects of indoor air pollution can range from mild allergies and respiratory issues to more severe problems such as respiratory diseases, heart disease, and cancer. It is important to take steps to improve indoor air quality and reduce exposure to pollutants.

Older people, children, and those with respiratory diseases are more vulnerable to indoor air pollution

People spend approximately 90% of their time indoors, where the air can be more polluted than outdoors, increasing the risk of illness. Indoor air pollution can come from natural sources, human-made sources, and combustion. Natural sources include bacteria, moulds, and pollen, while human-made sources include volatile organic compounds (VOCs) from furniture, paneling, and carpets, as well as formaldehyde from building materials and upholstery.

Older people, those with impaired health, and children are generally more vulnerable to indoor air pollution. This heightened sensitivity is due to various factors, including the concentration of the pollutant, as well as genetic factors, lifestyle, and age. People suffering from respiratory diseases are also more likely to be strongly affected by indoor air pollution.

The effects of indoor air pollution can vary from discomfort to more serious health issues. Some common symptoms associated with indoor air pollution include nosebleeds, chronic sinus infections, headaches, and sensory irritations. In more severe cases, individuals may experience a loss of balance or memory, chronic fatigue, difficulty speaking, and allergic reactions.

To mitigate the impact of indoor air pollution, it is essential to ensure proper ventilation in buildings. Ventilation systems and open windows can help dilute indoor pollutants with fresh outdoor air. Additionally, education plays a crucial role in raising awareness about the sources and potential health risks of indoor air pollution, empowering individuals to take preventive measures.

Overall, older individuals, children, and those with respiratory conditions are at an increased risk of adverse health effects from indoor air pollution. It is important to prioritize their well-being by maintaining good ventilation, minimizing indoor pollutants, and seeking medical attention if any concerning symptoms arise.

Radon gas is the second most common cause of lung cancer

Indoor air pollution is a serious issue, with the air we breathe inside our homes often more polluted than outdoor air. This is particularly true for pollutants like radon, a radioactive gas that is the second most common cause of lung cancer. Radon is produced by the decay of uranium, thorium, and radium in rocks and soil. It is invisible, odourless, and tasteless, making it difficult to detect without testing.

Radon gas can enter homes through cracks in floors, walls, or foundations, and it can also be released from building materials or groundwater. Inadequate ventilation can cause radon levels to build up indoors, increasing the risk of lung cancer for those exposed. Radon has been found to increase lung cancer risk by eight to nine times in smokers compared with non-smokers. According to estimates, radon is responsible for about 15,000 to 22,000 lung cancer deaths in the United States each year, with a significant proportion occurring in smokers.

The link between radon and lung cancer has been established through studies on uranium miners and residential exposure. Radon decays quickly, releasing tiny radioactive particles that can damage lung cells when inhaled. These particles lodge themselves in the alveoli or attach to dust particles that reach the deep part of the lungs. The accumulation of radon in poorly ventilated areas, such as underground mines, has been associated with high rates of lung cancer among miners. Similar levels of radon have been detected in homes, particularly in well-insulated and tightly sealed houses built on soil rich in uranium, thorium, and radium.

The Environmental Protection Agency (EPA) in the United States recommends taking action to reduce radon levels in homes that exceed 4 picocuries per liter (pCi/L) of air. This is because lowering radon levels can potentially reduce lung cancer deaths by 2 to 4 percent. Radon mitigation systems are available to divert radon gas from under the basement floor to the outdoors, reducing the risk of exposure.

While smoking is the leading cause of lung cancer, the combination of radon gas exposure and cigarette smoke creates an even greater risk. However, it is important to note that radon also poses a significant danger to non-smokers, with thousands of radon-related lung cancer deaths occurring in this population. Overall, radon is a serious health hazard that contributes to a significant number of lung cancer cases, making it crucial for individuals to test their homes and take appropriate measures to reduce exposure.

Environmental tobacco smoke (secondhand smoke) increases the risk of heart disease and cancer

Indoor air pollution is a serious issue, with the air we breathe inside our homes and buildings often more polluted than outdoor air. One of the major contributors to indoor air pollution is environmental tobacco smoke (ETS), also known as secondhand smoke. ETS is a mixture of sidestream smoke from the burning tip of a cigarette and mainstream smoke exhaled by the smoker. It contains numerous toxic chemicals, including nicotine and cancer-causing agents (carcinogens). Exposure to ETS poses significant health risks, especially increasing the chances of heart disease and cancer.

Secondhand smoke has detrimental effects on the heart and blood vessels, elevating the likelihood of a heart attack. Research indicates that non-smokers exposed to ETS have a 25-30% higher risk of developing heart disease and a 20-30% increased chance of suffering a stroke. The harmful effects of ETS on the cardiovascular system are immediate, with even brief exposure causing damage to blood vessel linings and increasing the stickiness of blood platelets, thus elevating the risk of a heart attack.

ETS is a well-established cause of lung cancer, as recognised by the U.S. Environmental Protection Agency, the U.S. National Toxicology Program, the U.S. Surgeon General, and the International Agency for Research on Cancer. It is responsible for over 7,000 lung cancer deaths annually among non-smoking adults in the United States alone. The danger of ETS is not limited to lung cancer, as evidence suggests it may also increase the risk of other cancers in adults, including breast cancer, nasal sinus cavity cancer, and nasopharyngeal cancer.

The impact of ETS extends to reproductive health as well. Exposure during pregnancy can lead to adverse outcomes such as reduced fertility, pregnancy complications, low birth weight, preterm birth, and lung problems in newborns. Additionally, infants exposed to secondhand smoke are at a higher risk of sudden infant death syndrome (SIDS), the leading cause of death in otherwise healthy infants. ETS also contributes to respiratory issues in children, increasing the frequency and severity of asthma attacks, respiratory infections, ear infections, and other respiratory ailments.

The dangers of ETS are not limited to any specific group, but young children are particularly vulnerable. They are more susceptible to the harmful effects of ETS and have less control over their exposure, as it mostly occurs in their homes due to smoking by adults. The long-term presence of ETS in indoor spaces can have severe consequences for the health of children, emphasising the importance of smoke-free environments, especially in homes and public spaces frequented by children.

Poor ventilation increases indoor pollutant levels

Poor ventilation increases indoor air pollution levels. Inadequate ventilation can increase indoor air pollution levels by not bringing in enough outdoor air to dilute emissions from indoor sources and by not carrying indoor air pollutants out of the home. Outdoor air can enter and leave a building by infiltration, natural ventilation, and mechanical ventilation. Infiltration occurs when outdoor air flows into buildings through openings, joints, and cracks in walls, floors, and ceilings, and around windows and doors. Natural ventilation is when air moves through opened windows and doors. Finally, mechanical ventilation involves the use of devices such as fans and ductwork to continuously remove indoor air and distribute filtered and conditioned outdoor air.

The rate at which outdoor air replaces indoor air is described as the air exchange rate. When there is little infiltration, natural ventilation, or mechanical ventilation, the air exchange rate is low, and indoor air pollution levels can increase. This is especially true for buildings designed and constructed to minimize the amount of outdoor air that can "leak" in and out. However, weather conditions can also affect the amount of outdoor air that enters a building, and pollutants can build up even in "leaky" homes.

High temperature and humidity levels can also increase the concentrations of some indoor air pollutants. For example, standing water, water-damaged materials, and wet surfaces can serve as breeding grounds for moulds, mildews, bacteria, and insects. Controlling the relative humidity level in a home can help minimize the growth of these sources of biological pollutants.

Additionally, certain activities carried out in the home, such as smoking, using unvented or malfunctioning stoves, furnaces, or space heaters, and using cleaning products and pesticides, can release indoor air pollutants intermittently. High pollutant concentrations can remain in the air for long periods after these activities.

To improve indoor air quality, it is important to increase ventilation by opening windows and doors, using window or attic fans, or running air conditioners with the vent control open. Mechanical ventilation systems can also be installed to bring outdoor air into the home.

Building-related illnesses are caused by toxic moulds or bacteria

Indoor air pollutants can come from natural sources, human-made sources, and combustion. Common human-made indoor air pollutants include Volatile Organic Compounds (VOCs) from furniture, paneling, and carpets, and formaldehyde from building materials, furniture upholstery, and carpeting. Common combustion air pollutants include carbon monoxide and radon gas.

Mould is a type of fungus that lives on plant and animal matter. Mould grows best in damp and poorly ventilated areas, and reproduces by making spores. Airborne mould spores are commonly found in both indoor and outdoor environments. Mould can grow on building materials like wood and gypsum plasterboard and furnishings like carpet and curtains.

Mould-related illnesses can be caused by exposure to damp, mouldy home and workplace environments. Mould can cause allergic reactions, asthma episodes, irritations of the eye, nose and throat, sinus congestion, and other respiratory problems. Mould exposure can also lead to respiratory infections, exacerbation of asthma, and allergic fungal sinusitis.

Mould can be prevented by reducing moisture levels and regularly ventilating homes.

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