Indoor Air Pollution: Who Is At Risk?

Indoor air pollution is a pressing issue that affects almost everyone, especially those with pre-existing health conditions and children. Spending up to 90% of their time indoors, people are constantly exposed to various pollutants, such as lead, dust mites, mould, radon, pests, carbon monoxide, pet dander, and second-hand smoke. The effects of indoor air pollution can be immediate, causing irritation to the eyes, nose, and throat, headaches, dizziness, and fatigue, and worsened asthma symptoms. Moreover, long-term exposure can lead to respiratory diseases, heart disease, and cancer.

Children are at a higher risk of developing negative health effects due to their developing bodies and increased exposure to toxins through breathing, eating, and drinking. They are also more susceptible to environmental triggers for asthma, which can lead to exacerbated symptoms or asthma attacks.

The impact of indoor air pollution is not limited to health problems but also extends to lower academic performance and higher absenteeism in schools.

Children in schools

Children are especially vulnerable to the effects of indoor air pollution, as their bodies and immune systems are still developing. Poor indoor air quality in schools can have a detrimental impact on students' health, performance, and overall well-being.

Sources of Indoor Air Pollution in Schools

Indoor air pollution in schools can arise from various sources, including outdoor air infiltration, inadequate ventilation, and the use of specific building materials and furnishings. Outdoor air containing pollutants can enter school buildings through windows, doors, and ventilation systems. Inadequate ventilation can further increase indoor pollutant levels by trapping pollutants inside and not introducing enough fresh outdoor air.

Building materials and furnishings, such as deteriorated asbestos-containing insulation, newly installed flooring or upholstery, cabinetry made from pressed wood products, and cleaning or maintenance products, can release toxic chemicals and particles into the indoor air.

Health Effects of Indoor Air Pollution on Children in Schools

The health effects of indoor air pollution on children in schools can range from immediate to long-term impacts. Irritation of the eyes, nose, and throat, headaches, dizziness, and fatigue are some of the immediate symptoms that may occur shortly after exposure to indoor air pollutants. More severe and long-term health effects include respiratory diseases, heart disease, and cancer.

Children with pre-existing conditions, such as asthma, are particularly vulnerable to the effects of indoor air pollution in schools. Asthma symptoms can be triggered and exacerbated by exposure to indoor air pollutants, leading to increased school absenteeism.

Additionally, indoor air pollution can have cognitive and developmental impacts on children. Exposure to pollutants can affect neurodevelopment and cognitive ability and increase the risk of asthma, childhood cancer, and chronic diseases later in life.

Strategies to Improve Indoor Air Quality in Schools

To protect the health and well-being of children in schools, it is essential to implement strategies to improve indoor air quality. This can include enhancing ventilation systems, using air purifiers or filtration systems, and regular monitoring of indoor air quality.

Source control is also crucial, such as reducing the use of toxic cleaning and maintenance products, ensuring proper maintenance of heating and cooling systems, and choosing low-emission building materials and furnishings.

Furthermore, promoting outdoor physical activity and creating "clean air zones" around schools can help reduce children's exposure to air pollutants.

By addressing these issues, schools can create a healthier and more conducive learning environment for students.

Asthma-prone individuals

• Exposure to outdoor pollutants, such as ozone, nitrogen dioxide, and particulate matter, can induce asthma symptoms, exacerbations, and decreases in lung function.
• Active tobacco smoking is associated with poorer asthma control, while exposure to second-hand smoke increases the risk of asthma exacerbations, respiratory symptoms, and healthcare utilization.
• Other indoor pollutants, such as heating sources and moulds, can also negatively impact the course of asthma.
• The effects of indoor air pollution on asthma may be modified by other factors, such as obesity and genetic variations.

The elderly

As people age, their bodies become less able to compensate for the effects of environmental hazards. Air pollution can aggravate pre-existing health conditions, such as heart disease, stroke, lung diseases (e.g., chronic obstructive pulmonary disease and asthma), and diabetes. This can lead to increased medication use, more visits to healthcare providers, emergency room admissions, hospitalisations, and even death.

Cardiovascular and Respiratory Diseases

Mental Disorders

Air pollution has been found to have adverse effects on mental health, particularly in the elderly. Long-term exposure to air pollution has been linked to faster cognitive decline in older adults, with pollutants such as particulate matter and ozone being significant contributors.

Chronic Diseases

Air pollution can also worsen existing chronic diseases in the elderly. For example, exposure to air pollutants can increase the risk of heart attacks, especially in those who are diabetic or obese. It can also aggravate conditions like asthma and chronic obstructive pulmonary disease (COPD).

Cancer

While less commonly studied in relation to indoor air pollution, there is some evidence suggesting a link between air pollution and cancer, particularly lung cancer.

People with cardiovascular or respiratory diseases

Indoor air pollution can cause a range of adverse health effects, from irritation of the eyes, nose, and throat, to headaches, dizziness, fatigue, and more serious issues such as respiratory diseases, heart disease, and cancer. These effects may be felt shortly after exposure or years later.

Some indoor air pollutants, such as radon, particle pollution, carbon monoxide, and Legionella bacterium, are known to be linked to specific adverse health effects. For example, radon is the second leading cause of lung cancer, and short-term exposure to elevated carbon monoxide levels can be lethal.

Additionally, indoor air pollution can increase the risk of cardiovascular events. Scientific studies have shown that exposure to indoor air pollution can lead to increased cardiovascular morbidity and mortality. Fine particulate matter, in particular, has been linked to increased incidences of specific acute cardiovascular diseases, such as myocardial infarction, ischemic stroke, heart failure, cardiac arrhythmia, and atrial fibrillation.

Furthermore, indoor air pollution can also affect blood pressure. Studies have shown that exposure to particulate matter and ozone is associated with increased blood pressure, which is a risk factor for cardiovascular disease.

Overall, indoor air pollution poses a significant risk to people with cardiovascular or respiratory diseases, and it is important to take steps to improve indoor air quality to reduce potential health risks.

Pregnant women

Indoor air pollution can have adverse effects on pregnant women and their babies. Spending most of their time indoors, pregnant women are at a higher risk of being exposed to indoor air pollution.

Effects of indoor air pollution on pregnant women

• Respiratory health effects: Exposure to indoor air pollution during pregnancy has been associated with respiratory issues such as acute and chronic changes in pulmonary function, increased risk of respiratory diseases, and sensitisation of the airways to allergens.
• Allergic diseases: Indoor air pollution can cause allergic asthma and extrinsic allergic alveolitis, which is a type of lung inflammation.
• Cancer and effects on reproduction: Indoor air pollution has been linked to an increased risk of lung cancer and effects on human reproduction.
• Sensory effects and other effects on the nervous system: Indoor air pollution can cause sensory effects such as mucosal irritation and olfactory warnings of exposure to harmful environmental factors. It may also have effects on the nervous system, including behavioural abnormalities and toxic damage to nerve cells.
• Cardiovascular effects: Indoor air pollution has been associated with an increased risk of cardiovascular diseases, including hypertension, type 2 diabetes, and heart disease.

Reducing the effects of indoor air pollution

• Source management: This involves source removal, source substitution, and source encapsulation. For example, using less toxic materials or sealing surfaces of pressed wood products can help reduce exposure to indoor air pollution.
• Local exhaust: Using local exhaust systems can help remove pollutants before they spread into the indoor air.
• Ventilation: Improving ventilation by increasing the amount of outdoor air that comes indoors can help dilute the concentration of indoor pollutants.
• Exposure control: Adjusting the time and location of activities can help reduce exposure to indoor air pollution. For example, stripping and waxing floors after school is dismissed can help reduce students' exposure to indoor air pollution.
• Air cleaning: Using air filters can help remove particles from the air.

Frequently asked questions