Indoor Air Quality: A Silent Killer Exposed

Air pollution is a significant global health and environmental issue, and it is one of the leading risk factors for death and poor health. In 2021, air pollution was responsible for approximately 8.1 million deaths worldwide, with 500,000 of these being children under five years old. While outdoor air pollution is a major concern, indoor air pollution also plays a significant role in premature mortality. This introduction will explore the percentage of deaths caused by indoor air pollution and the factors contributing to this issue.

In 2020, 3.2 million people died from indoor air pollution

Air pollution is a serious issue that affects people worldwide. In 2020, 3.2 million people died from indoor air pollution, according to the World Health Organization (WHO). This is a significant number and highlights the importance of addressing indoor air pollution to protect public health.

Indoor air pollution, also known as household air pollution, is caused by various factors, including the use of solid fuels and kerosene for cooking and heating, as well as inefficient combustion devices and polluting fuels. These sources of pollution contribute to high levels of particulate matter, black carbon, methane, and other pollutants in the air, which can have detrimental effects on human health.

The health risks associated with indoor air pollution are significant. Exposure to indoor air pollution can cause non-communicable diseases such as ischaemic heart disease, stroke, chronic obstructive pulmonary disease (COPD), and lung cancer. It is also a risk factor for acute lower respiratory infections in adults and children. According to WHO data, indoor air pollution is responsible for 32% of ischaemic heart disease deaths, 23% of stroke deaths, 21% of lower respiratory infection deaths, and 19% of COPD deaths.

Additionally, indoor air pollution disproportionately affects women and children, who typically bear the responsibility of household chores such as cooking and collecting firewood. The use of polluting fuels and technologies in homes puts them at a greater risk of exposure to harmful pollutants. Furthermore, indoor air pollution caused by energy poverty contributes to outdoor air pollution, impacting the health of entire communities.

Addressing indoor air pollution requires a multifaceted approach. Promoting the use of clean fuels and technologies, such as solar, electricity, biogas, and liquefied petroleum gas (LPG), can significantly reduce indoor air pollution levels. Additionally, improving access to electricity and energy efficiency can help reduce the reliance on polluting devices and fuels. By implementing policies and initiatives that support sustainable land use, cleaner household energy, and energy-efficient housing, we can effectively reduce indoor air pollution and protect the health and well-being of millions of people worldwide.

Women and children are most affected by indoor air pollution

Indoor air pollution is a major public health hazard, particularly in developing countries where the use of fossil fuels is prevalent. It is estimated to cause 3.2 million deaths per year, with women and children bearing the brunt of its adverse effects. They are particularly vulnerable due to their increased exposure to indoor environments and the specific chores they undertake within them.

Women and children spend a significant amount of time indoors, with 90% of their working hours occurring in these settings. In low-income households, women and children are often responsible for household tasks such as cooking, heating, and collecting firewood. These activities directly expose them to harmful pollutants emitted from solid fuels, biomass combustion, and inefficient stoves. The use of biomass fuels, including wood fuel and kerosene, has been linked to increased coughing, phlegm, wheezing, eye problems, and headaches among women and children.

The lack of proper ventilation in many households, especially in rural areas, exacerbates the problem by trapping pollutants indoors. This results in high levels of particulate matter and carbon monoxide (CO) emissions, which have severe health consequences. Women and children in these environments often experience respiratory issues such as congestion, breathing difficulties, and asthma. Additionally, indoor air pollution impacts the development of children's endocrine glands, nervous, and immune systems, making them more susceptible to infectious diseases.

The use of polluting fuels and technologies further contributes to the health burden on women and children. They are at risk of injuries and violence while gathering fuel, and the ingestion of kerosene is a leading cause of childhood poisonings. The time spent using and preparing fuel for inefficient devices takes away from opportunities for health, education, and development.

Addressing indoor air pollution is crucial to protect the health and well-being of women and children. This can be achieved by increasing access to clean fuels and technologies, such as solar, electricity, biogas, and liquefied petroleum gas (LPG), as well as improving ventilation and kitchen management practices to reduce exposure to harmful pollutants.

Incomplete combustion of solid fuels and kerosene used for cooking causes indoor air pollution

Air pollution is a leading risk factor for death, causing 8.1 million deaths globally in 2021. This includes deaths caused by both indoor and outdoor air pollution. Incomplete combustion of solid fuels and kerosene used for cooking is a major contributor to indoor air pollution, which has severe health impacts.

Solid cooking fuels, such as wood, crop waste, charcoal, coal, and dung, are commonly used by people in low- and middle-income countries, with 2.1 billion people relying on these fuels for cooking. The incomplete combustion of these solid fuels releases particulate matter and other pollutants, such as black carbon and methane, which have harmful effects on human health. These pollutants can penetrate deep into the lungs and enter the bloodstream, causing inflammation and impairing immune response and oxygen-carrying capacity.

Kerosene, a middle distillate similar to diesel, is also widely used for household cooking and lighting, particularly in households without adequate electricity access. Kerosene combustion produces fine particulate matter (PM2.5) that can reach levels 100 times higher than acceptable in poorly ventilated dwellings. Exposure to PM2.5 from kerosene combustion has been linked to adverse health outcomes, including respiratory infections, cardiovascular disease, and lung cancer.

The World Health Organization (WHO) has issued guidelines for indoor air quality and household fuel combustion, recommending against the use of kerosene and unprocessed coal. These guidelines provide evidence-based guidance on clean fuels and technologies, emphasizing the need to address all household energy uses, especially cooking, to protect health and the environment.

The impact of indoor air pollution from incomplete combustion of solid fuels and kerosene is significant, with an estimated 3.2 million premature deaths attributed to household air pollution each year. This problem is particularly acute in low- and middle-income countries, where access to clean cooking alternatives is limited. By addressing indoor air pollution through the adoption of clean fuels and technologies, significant health benefits can be achieved, reducing the global burden of air pollution-related deaths and diseases.

500,000 child deaths were linked to household air pollution in 2021

Air pollution is a leading risk factor for death, killing 8.1 million people globally in 2021. It has become the second-leading risk factor for death in terms of the total global population, as well as in children under five years old. In 2021, exposure to air pollution was linked to more than 700,000 deaths of children under five years old, making it the second-leading risk factor for death globally for this age group, after malnutrition.

A significant number of these deaths, around 500,000, were linked to household air pollution. This is due to cooking indoors with polluting fuels, mostly in Africa and Asia. The use of inefficient and polluting fuels and technologies in and around the home releases a range of health-damaging pollutants, including small particles that penetrate deep into the lungs and enter the bloodstream. Indoor smoke can have levels of fine particles up to 100 times higher than acceptable in poorly ventilated dwellings. Exposure is particularly high among women and children, who spend the most time near the domestic hearth.

The impact of air pollution on child health is striking, with the death rate in children under five in East, West, Central, and Southern Africa 100 times higher than in high-income countries. UNICEF Deputy Executive Director Kitty van der Heijden has emphasized the profound effects of inaction on the next generation, urging governments and businesses to take meaningful, child-focused action to reduce air pollution and protect children's health.

While global death rates from air pollution have declined in recent decades, the burden of air pollution remains higher in low and middle-income countries. This is due to a reliance on solid fuels for cooking in low-income countries and increasing outdoor air pollution as countries industrialize and transition to middle-income status. However, it is important to note that the decline in death rates is primarily driven by improvements in indoor air pollution, with more modest improvements in outdoor pollution.

The World Health Organization's (WHO) 2021 air quality guidelines highlight the dangers of indoor air pollution, particularly for children, as their developing bodies are more susceptible to serious complications. Indoor air pollution is linked to inequality and poverty, with roughly three billion people across the poorest nations relying on unclean sources of fuel.

Indoor air pollution is one of the leading risk factors for death

Indoor air pollution is a significant contributor to the global disease burden and is one of the leading risk factors for death. While the total number of deaths attributed to air pollution is challenging to determine due to overlapping risk factors, various studies and reports provide valuable insights into the impact of indoor air pollution on mortality.

The World Health Organization (WHO) and the IHME's Global Burden of Disease study are two widely recognized sources for estimating the death toll from air pollution. In 2012, the WHO estimated that indoor air pollution was linked to 4.3 million deaths in households cooking with coal, wood, and biomass stoves. This estimate considered improved information about pollution exposure among the approximately 2.9 billion people using these fuel sources. Additionally, the IHME's Global Burden of Disease study for 2021 reported that nearly every person on Earth breathes unhealthy levels of air pollution daily, with far-reaching health implications.

The impact of indoor air pollution on mortality is particularly pronounced in low- and middle-income countries. In these regions, the reliance on solid fuels for cooking and the use of polluting fuels and technologies contribute to high indoor pollution rates. For example, in 2020, household air pollution was responsible for an estimated 3.2 million deaths per year, including over 237,000 deaths of children under five. Furthermore, indoor air pollution caused by incomplete combustion of solid fuels and kerosene used for cooking leads to illnesses that claim 3.2 million lives annually. Among these deaths, 32% are from ischaemic heart disease, 23% from stroke, and 21% from lower respiratory infections.

The use of polluting fuels and stoves for cooking has led the WHO to issue guidelines for indoor air quality, emphasizing the importance of transitioning to clean fuels and technologies. These guidelines aim to reduce the health risks associated with indoor air pollution, particularly for women and children, who are often responsible for household chores and spend more time at home, exposing them to unhealthy air.

While the decline in overall air pollution-related deaths since 1990 is encouraging, indoor air pollution remains a critical issue. Addressing indoor air pollution is crucial to reducing the global disease burden and mitigating its impact on human health, especially in vulnerable populations.

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