Air Pollution Database: Global Health Impact Insights

Air pollution is a significant environmental and health concern, contributing to the global disease burden and causing respiratory and other diseases. According to the World Health Organization (WHO), 99% of the global population lives in areas where air pollution levels exceed the recommended guideline limits. To address this issue, WHO offers technical support to its member states and actively monitors and reports on global trends and changes in health outcomes related to air pollution. WHO's Global Air Pollution Database provides valuable information and resources to mitigate the risks associated with air pollution, improve public health, and reduce the environmental impact. This database is a crucial tool in the global effort to combat the adverse effects of air pollution and protect the well-being of people worldwide.

Ambient air pollution

The World Health Organization (WHO) estimates that ambient air pollution caused approximately 4.2 million premature deaths globally in 2016, with 58% attributed to ischaemic heart disease and strokes, 18% to chronic obstructive pulmonary disease, 18% to acute lower respiratory infections, and 6% to lung cancer. By 2019, the number of deaths remained at 4.2 million, with 68% due to ischaemic heart disease and stroke, 14% due to chronic obstructive pulmonary disease, 14% due to acute lower respiratory infections, and 4% due to lung cancer. Notably, 89% of these premature deaths occurred in low- and middle-income countries, with the highest numbers in the WHO South-East Asia and Western Pacific Regions.

The impact of ambient air pollution extends beyond premature deaths, as it also contributes to the global disease burden. It affects both the quality and expectancy of life, ranking high among risk factors for poor health worldwide. Short-term exposure to elevated pollution levels can cause adverse health effects, including impaired lung function, exacerbated asthma, and increased hospital admissions for respiratory and cardiovascular issues. There is also emerging evidence linking air pollution to potential brain health risks, such as dementia and cognitive decline, as well as early-life impacts like low birth weight.

To address ambient air pollution, the WHO's Air Quality and Health Unit focuses on three key areas: knowledge, evidence, and measuring progress; institutional capacity building and technical support; and leadership and coordination. Successful policies to reduce air pollution include adopting clean technologies, improving waste management, promoting access to clean household energy, transitioning to clean power generation, prioritizing sustainable urban planning, and increasing the use of low-emission fuels and renewable energy sources. These measures aim to protect public health and reduce the key sources of outdoor air pollution.

Household combustion devices

The health effects of combustion pollutants can be severe. Carbon monoxide, for example, can cause headaches, fatigue, and queasiness at elevated levels, and brain and heart damage or even death at very high levels. Other combustion pollutants can irritate the eyes, nose, and throat and contribute to lung disease, cancer, and other serious health issues. Exposure to smoke from cigarettes and wood-burning, for instance, is linked to cardiovascular and respiratory diseases.

To reduce exposure to household combustion pollutants, the California Air Resources Board (CARB) recommends regular cleaning to remove house dust particles, especially in homes with children or pets. Vacuuming rugs and furniture with an efficient vacuum cleaner and damp-mopping floors can help reduce indoor particle levels. Additionally, leaving shoes by the door and using doormats can minimize the amount of dirt and dust brought into the home.

For homes with fuel-type appliances or attached garages, CARB advises installing carbon monoxide detectors or alarms as per California law. To prevent the escape of pollutants into the home, CARB recommends using "sealed combustion" or "direct vent" gas appliances with exhaust vents and air supplies sealed from the indoors. It is also important to avoid using leaking or malfunctioning wood-burning appliances and to have wood stoves and fireplaces inspected annually for any issues.

The World Health Organization (WHO) has recognized the negative health impacts of household air pollution caused by the incomplete combustion of solid fuels and kerosene used for cooking. In response, WHO has developed guidelines for indoor air quality and household fuel combustion, offering recommendations on clean fuels and technologies and strategies for transitioning to cleaner alternatives. These guidelines aim to protect health and promote the adoption of healthier household fuels and technologies globally.

Industrial facilities

The WHO has developed the Ambient Air Quality Database to address this global issue. This database compiles ground measurements of annual mean concentrations of nitrogen dioxide (NO2) and particulate matter with diameters of 10 μm or smaller (PM10) and 2.5 μm or smaller (PM2.5). These measurements are taken in urban areas, including urban backgrounds, residential, commercial, mixed, and rural areas, as well as industrial zones close to urban settlements. The data is intended to represent human exposure to air pollution and is used to calculate the Sustainable Development Goal Indicator 11.6.2 for air quality in cities. The database is regularly updated every 2-3 years and serves as a valuable tool for monitoring and improving air quality on a global scale.

The WHO also plays a crucial role in promoting interventions and initiatives for healthy sectoral policies. These policies encompass various aspects such as energy, transport, housing, urban development, and the electrification of healthcare facilities. By addressing key health risks associated with indoor and outdoor air pollution, the WHO strives to mitigate the adverse effects of air pollution on human health. Additionally, the organization provides technical support to its member states by offering guidance, tools, and authoritative advice on health issues related to air pollution and its sources.

Furthermore, the WHO has implemented a strategy to raise awareness about the risks of air pollution and the potential solutions to reduce those risks. Through digital outreach and partnerships, the organization has engaged with health and environment ministries, city governments, and stakeholders from high-emission sectors. These collaborative efforts aim to highlight the importance of addressing air pollution for both health and environmental benefits. By working with countries to monitor and improve air quality, the WHO is actively contributing to the global efforts to reduce air pollution and its impact on human health and ecosystems.

Air pollution health risks

Air pollution is the presence of contaminants in the atmosphere, such as dust, fumes, gases, odours, smoke, or vapours, in quantities that can be harmful to human health. It is a significant risk factor for many of the leading causes of death, including heart disease, stroke, lower respiratory infections, lung cancer, diabetes, and chronic obstructive pulmonary disease (COPD). The health effects of air pollution are far-reaching, impacting nearly every organ in the body.

One of the main pathways of exposure to air pollution is through the respiratory tract. Pollutants such as fine particulate matter (PM2.5 and PM10) can penetrate deep into the lungs, enter the bloodstream, and travel to other organs, causing systemic damage to tissues and cells. This can lead to inflammation, oxidative stress, immunosuppression, and mutagenicity, ultimately leading to disease. Long-term exposure to fine particulate matter increases the risk of developing non-communicable diseases with longer onsets, such as heart disease, stroke, and cancer. Short-term exposure to high levels of particulate matter can lead to reduced lung function, respiratory infections, and aggravated asthma.

Children are particularly vulnerable to the health risks associated with air pollution. Higher levels of air pollution increase the risk of short-term respiratory infections, leading to more school absences. Children who play outdoor sports and live in high-ozone communities are more likely to develop asthma. Living in communities with higher pollution levels can cause lung damage and increase the risk of cognitive and emotional problems later in life. Additionally, air pollution has been linked to adverse pregnancy outcomes, such as low birth weight and small gestational age.

The health risks associated with air pollution are not evenly distributed among the population. People of colour are more likely to be exposed to air pollution and suffer more significant harm to their health. This disparity is often due to systemic racism, which has historically placed people of colour in more polluted areas. Additionally, those with lower incomes tend to live closer to pollution sources and have fewer resources to relocate or protect themselves from the harmful effects of air pollution.

While global death rates from total air pollution have declined in recent decades, this improvement is primarily driven by a reduction in indoor air pollution. Improvements in outdoor pollution have been more modest. Thus, air pollution remains a significant health and environmental concern worldwide, contributing to premature deaths and reducing the quality of life for many.

Morbidity and mortality

Air pollution is a major threat to health across the globe. According to the World Health Organization (WHO), 99% of the global population breathes air that exceeds WHO guideline limits and contains high levels of pollutants. This has significant implications for morbidity and mortality, with air pollution contributing to a range of diseases and causing premature deaths.

The WHO Ambient Air Quality Database compiles data on ground measurements of annual mean concentrations of nitrogen dioxide (NO2) and particulate matter (PM10 and PM2.5). These pollutants originate mainly from human activities related to fossil fuel combustion. The database aims to represent an average for urban areas, as human exposure to air pollution is of primary concern. The data is used to monitor and assess the health impacts of air pollution, including morbidity and mortality.

Air pollution has been identified as one of the leading risk factors for death and a contributor to the global disease burden. It is associated with respiratory infections and diseases, lung cancer, cardiovascular diseases such as stroke and heart disease, and chronic obstructive pulmonary disease (COPD). In 2019, an estimated 4.2 million people died from breathing poor-quality air, developing these cardiovascular and respiratory conditions.

The impact of air pollution on morbidity and mortality is not limited to physical health. Studies have shown that air pollution is also associated with an increased risk of chronic diseases such as dementia, diabetes, and kidney disease. Additionally, air pollution can affect the quality of life, contributing to disability-adjusted life years (DALYs) and years of life lost (YLL). In recent years, air pollution has contributed to one in ten deaths globally, with low-income countries often bearing the highest burden.

To address the health risks posed by air pollution, strong policies and interventions are necessary. This includes reducing emissions from vehicles, prioritizing sustainable transport, implementing stricter emission standards, and improving energy efficiency in cities. Additionally, promoting healthy diets and sustainable agricultural practices can help reduce air pollution and improve overall health outcomes. By addressing air pollution, policies can offer a "win-win" strategy for both climate and health, reducing the burden of diseases attributed to air pollution.

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