You may just not realise it but the air you breathe inside your home (or office) may even be more hazardous than outside air because of household air pollution.
Causes of household air pollution
According to the World Health Organisation (WHO), around 2.6 billion people still cook and warm their homes using open fires and stoves that use solid fuels such as coal or wood. In Australia, just cooking with gas stoves have been found to be a cause of household air pollution as well.
Stanford University's previous research found gas stoves in American households could emit the greenhouse gas methane, even when they were not switched on. More recently, a study of kitchen air quality after using gas stoves found that levels of nitrogen dioxide (NO2) reaches up to five times higher than the Australian outdoor air quality standard.
Chances of indoor air pollution are especially high during winter where houses and offices are usually kept shut. Without the proper conditioning and circulation of air, dangers to you and your family's health only get worse.
According to the WHO, 3.2 million people die prematurely every year from illnesses attributable to household air pollution caused by the incomplete combustion of solid fuels and kerosene used for cooking. Particulate matter and other pollutants in household air pollution inflame the airways and lungs, impair immune response and reduce the oxygen-carrying capacity of the blood.
Health risks from household air pollution
We may already be aware of the common health issues that arise from poor indoor air quality such as asthma and allergies, so let's take a look now at some of the lesser known health risks of household air pollution:
Ischaemic heart disease
Ischaemic heart disease (IHD) is a major cause of mortality and morbidity in the world today. It is a condition where the arteries supplying oxygen to the heart become narrowed or blocked, leading to reduced blood flow and cardiac tissue damage. Household air pollution—from burning fuel such as wood, charcoal, and kerosene—has been linked with an increased risk of IHD.
The WHO estimates that over 3 billion people are exposed to household air pollution from cooking with solid fuels in their homes. This form of exposure can result in elevated levels of carbon monoxide, nitrogen dioxide, particulate matter, polycyclic aromatic hydrocarbons and other pollutants which may contribute to IHD by inducing inflammation or damaging endothelial cells that line the walls of coronary arteries.
According to the WHO report, 12% of all deaths due to ischaemic heart disease, accounting for over a million premature deaths annually, can be attributed to exposure to household air pollution.
Stroke is a debilitating medical condition that affects people of all ages, genders and backgrounds. It is caused by an interruption to blood flow in the brain due to a blocked artery or rupture of a blood vessel, resulting in lack of oxygen and nutrients to the brain cells. This can lead to disabilities such as paralysis, memory loss, speech difficulties and impaired cognition.
One risk factor for stroke that many people are unaware of is household air pollution from burning fuels such as wood, coal or kerosene for cooking and heating purposes. Inhaling this polluted air increases a person’s risk of stroke due to particulate matter entering their lungs, eventually making its way into the bloodstream and causing damage to vessels within the brain.
According to the WHO report, approximately 12% of all deaths due to stroke can be attributed to the daily exposure to household air pollution arising from using solid fuels and kerosene at home. Stroke is one of the leading causes of death in Australia.
Lower respiratory infection
Lower respiratory infection, or LRI, is a type of infection that affects the lower parts of the lungs. It can be caused by a variety of microorganisms such as bacteria, viruses, and fungi. Some common symptoms of LRI include coughing, difficulty breathing, chest pain, and fever. In severe cases it can lead to pneumonia.
Household air pollution is one known risk factor for developing an LRI. Burning fuel such as wood or charcoal releases large amounts of smoke particles into the air. These particles can then enter our bodies when we breathe them in and cause inflammation in our lungs leading to an increased risk of developing an LRI. Therefore it’s important to reduce household air pollution as much as possible to prevent LRIs from occurring.
Based on the WHO report, exposure to household air pollution almost doubles the risk for childhood LRI and is responsible for 44% of all pneumonia deaths in children less than 5 years old. Household air pollution is also a risk for acute lower respiratory infections in adults and contributes to 22% of all adult deaths due to pneumonia.
Chronic obstructive pulmonary disease (COPD)
Chronic obstructive pulmonary disease (COPD) is a progressive and irreversible lung condition that affects millions of people worldwide. It's estimated that COPD accounts for around 4% of deaths globally. This chronic respiratory disorder is usually caused by smoking, but environmental factors such as household air pollution can also increase the risk of developing it.
Long-term exposure to gases or particles from solid fuels burned in indoor cooking stoves and open fires for heating or lighting purposes has been linked to COPD, asthma, respiratory infections and other lung diseases. In fact, a Climate Council report released in 2021 found that gas cooking could have the same impact on children with asthma as passive smoking does.
The WHO attributes 23% of all deaths from chronic obstructive pulmonary disease (COPD) in adults in low- and middle-income countries to exposure to household air pollution.
Lung cancer is a leading cause of death worldwide, and household air pollution is an important factor. Lung cancer is caused by both environmental and genetic factors, but the primary risk factor for lung cancer is the inhalation of carcinogenic particles from air pollutants.
Household air pollution generated from burning kerosene, coal, or wood in stoves or open fires without proper ventilation can increase an individual’s risk of developing lung cancer. The smoke created by these types of fuels contains a variety of dangerous chemicals that are known to damage DNA and increase the risk of developing lung cancer.
In addition to household air pollution, other environmental triggers for lung cancer include occupational exposure to certain chemicals as well as radon gas exposure in homes.
The WHO estimates that 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.
Apart from the serious health issues mentioned above, there is also evidence of links between household air pollution and low birth weight, tuberculosis, cataract, nasopharyngeal and laryngeal cancers.
Indoor air pollution is a growing concern for many households, with rising levels of household air pollution caused by a variety of sources. Poor indoor air quality can lead to an increased risk of respiratory and cardiovascular illnesses, allergies, and other long-term health issues. To ensure the safety of your family's health, it is important to take actionable steps to improve the quality of your home's indoor air.
How to reduce household air pollution
Improve indoor air ventilation
Improving indoor air circulation can help in reducing the concentration of household air pollutants indoors. You can achieve natural ventilation simply by opening windows and letting the air in. However, depending on where you live, this might not be a suitable solution if your home is exposed to more outdoor pollutants such as pollen or exhaust fumes from cars.
In that case, an effective way of reducing household air pollution is by investing in an air purifier. An air purifier works by trapping indoor air pollutants. The WHO recommends HEPA air purifiers that can actively remove indoor air pollutants, including PM2.5 particulate matters.
Additionally, the results of a study on home interventions that are effective at decreasing indoor nitrogen dioxide concentrations show that placement of HEPA air purifiers with carbon filters can significantly decrease indoor NO2 concentrations. Choosing an air purifier with filters that eliminate smoke, odours and volatile organic compounds (VOCs) that are emitted from cleaning agents or furniture finishes will also help reduce household air pollution. Additionally, some models come with filters designed to remove bacteria and viruses from the air, helping keep your family healthy while they’re indoors.
Switch to clean energy alternatives
The Climate Council, Australia’s own independent, evidence-based organisation on climate science, impacts and solutions, recommends Australians to switch to clean energy alternatives like solar and wind.
“Gas is a fossil fuel that drives dangerous climate change, a health hazard, and a growing financial burden on Australian families. Getting gas out of our homes is good for our health, our economy, and our climate,” Dr Carl Tidemann, senior researcher at the Climate Council, said.
The study on home interventions to decrease indoor nitrogen dioxide concentrations also found that replacing unvented gas stoves with electric stoves significantly decrease indoor NO2 concentrations.
The Climate Council adds that although the upfront cost of replacing appliances can be a major barrier for many families, the shift from gas to efficient electric appliances can save money in the long term and be beneficial for our health.
Household air pollution is a serious health risk that should not be taken lightly. It can cause chronic and acute illnesses that can lead to disability and death. Taking steps to reduce air pollution in the home—such as using cleaner fuels, improved ventilation, and avoiding smoking indoors—can dramatically reduce the risks associated with household indoor air pollution. Additionally, homeowners should consider purchasing an air purifier to help remove particles from indoor air.
Disclaimer: The information provided in this article is for general reference only. Please seek advice from professionals according to your needs.