Air Pollution's Reach: How Many Are Affected?

Ambient air pollution is a pressing issue that affects billions of people worldwide. In 2019, an estimated 4.2 million premature deaths were attributed to outdoor air pollution, with 89% of these occurring in low- and middle-income countries. The primary sources of outdoor air pollution include residential energy use, vehicles, power generation, agriculture, and industry. Particulate matter (PM), a common proxy indicator for air pollution, includes harmful substances such as sulfates, nitrates, and black carbon, which can lead to cardiovascular and respiratory issues. Despite overall improvements in air quality since 1980, extreme weather events, droughts, and wildfires have contributed to worsening air pollution in certain regions, exposing a growing number of people to health risks.

In 2019, 99% of the global population lived in places where air quality did not meet WHO guidelines

In 2019, the World Health Organization (WHO) estimated that 99% of the global population lived in places where air quality did not meet its guidelines. This means that almost everyone in the world breathes polluted air that exceeds internationally approved limits, with negative health impacts kicking in at much lower levels than previously thought. The combined effects of ambient air pollution and household air pollution are associated with 6.7 million premature deaths annually, with 4.2 million of these attributed to outdoor air pollution.

Outdoor air pollution is a major environmental health problem affecting people in low-, middle-, and high-income countries. People living in low- and middle-income countries, however, experience the highest exposures and disproportionately bear the burden of outdoor air pollution, with 89% of the 4.2 million premature deaths occurring in these areas. The greatest burden is found in the WHO South-East Asia and Western Pacific Regions.

Outdoor air pollution in both cities and rural areas is caused by fine particulate matter, which results in strokes, heart diseases, lung cancer, acute and chronic respiratory diseases. Particulate matter (PM) is a common proxy indicator for air pollution, and there is strong evidence for the negative health impacts associated with exposure to this pollutant. The major components of PM are sulfates, nitrates, ammonia, sodium chloride, black carbon, mineral dust, and water. Carbon monoxide (CO) is a colourless, odourless, and toxic gas produced by the incomplete combustion of carbonaceous fuels such as wood, petrol, charcoal, natural gas, and kerosene. Ground-level ozone (O3) is formed through the reaction of gases in the presence of sunlight, and nitrogen dioxide (NO2) is a gas commonly released from the combustion of fuels in the transportation and industrial sectors.

Sources of outdoor air pollution include residential energy for cooking and heating, vehicles, power generation, agriculture/waste incineration, and industry. Natural sources of air pollution include windblown or kicked-up dust, dirt and sand, volcanic smoke, and burning materials. Manmade sources, which tend to be the leading contributors to air pollution in cities, primarily include various forms of combustion, such as from gas-powered transportation (planes, trains, and automobiles) and industrial activity.

Ambient air pollution is estimated to have caused 4.2 million premature deaths worldwide in 2019

Ambient air pollution is a serious issue that affects people worldwide, in both cities and rural areas. In 2019, it was estimated to have caused 4.2 million premature deaths globally. This figure underscores the significant impact of air pollution on public health and serves as a stark reminder of the urgent need to address this issue.

The primary cause of these premature deaths is exposure to fine particulate matter, which leads to cardiovascular and respiratory diseases, as well as cancers. According to the World Health Organization (WHO), 68% of outdoor air pollution-related premature deaths in 2019 were attributed to ischaemic heart disease and stroke. Additionally, 14% were due to chronic obstructive pulmonary disease, 14% to acute lower respiratory infections, and 4% to lung cancers.

The burden of outdoor air pollution disproportionately affects people in low- and middle-income countries, with 89% of the 4.2 million premature deaths occurring in these regions. The WHO South-East Asia and Western Pacific Regions bear the brunt of these deaths. This disparity highlights the social inequality inherent in the effects of air pollution, with vulnerable communities suffering the most.

The sources of ambient air pollution are diverse and interconnected. They include residential energy use for cooking and heating, vehicle emissions, power generation, waste incineration, and industrial activities. Addressing these sources requires a multifaceted approach, including policies and investments that promote sustainable practices. For instance, supporting cleaner transport, energy-efficient homes, and better waste management can significantly reduce outdoor air pollution levels.

Furthermore, the health risks associated with air pollution extend beyond premature deaths. Exposure to polluted air can lead to various chronic conditions, such as asthma, diabetes, and heart disease. Vulnerable groups, such as children, are especially susceptible to the harmful effects of air pollution, which can cause premature birth, low birth weight, and lung diseases. Therefore, addressing air pollution is crucial not only for reducing mortality rates but also for improving overall public health and well-being.

The major outdoor pollution sources include residential energy, vehicles, power generation, and industry

Ambient (outdoor) air pollution is a pressing issue, causing an estimated 4.2 million premature deaths worldwide in 2019. This figure represents the combined effects of ambient air pollution and household air pollution, with outdoor air pollution contributing 68% of these deaths. The major sources of outdoor pollution include residential energy, vehicles, power generation, and industry.

Residential energy use, including cooking, heating, and lighting, plays a critical role in daily life. However, the burning of solid fuels, such as wood, charcoal, coal, and kerosene, releases toxic pollutants like particulate matter, carbon monoxide, and black carbon, contributing to both indoor and outdoor air pollution. According to the World Health Organization (WHO), around 2.3 billion people lack access to clean cooking technologies, relying on rudimentary stoves or open fires. This issue disproportionately impacts women and girls and contributes to climate change and environmental degradation.

Vehicles are another significant source of outdoor air pollution. Cars, trucks, buses, off-road vehicles, and planes release pollutants directly through emissions and indirectly through the formation of secondary pollutants like ozone. Motor vehicles are the largest contributors to ground-level ozone, a common component of smog, in many urban areas. To address this, several measures have been implemented, including supporting the manufacture and sale of zero and low-emission vehicles, promoting cleaner fuels, and implementing vehicle emission control programs and inspection and maintenance initiatives.

Power generation, particularly the burning of fossil fuels for electricity production, contributes to outdoor air pollution through the release of fine particulate matter and gases like carbon monoxide and nitrogen oxides. The health impacts of power generation pollution vary based on factors such as race, income, and geography, with communities in low- and middle-income countries bearing a disproportionate burden.

Lastly, industrial activities, including the combustion of fuels, release pollutants such as nitrogen dioxide and other harmful emissions. To mitigate industrial pollution, policies promoting clean technologies, improved waste management, and the capture of methane gas emitted from waste sites have been implemented.

Addressing these major sources of outdoor pollution through concerted actions and policies at the local, national, and regional levels is crucial to improving air quality and protecting public health.

Communities of colour are disproportionately exposed to unhealthy air and are more likely to have chronic conditions

Air pollution is a significant environmental health problem, affecting people in low-, middle-, and high-income countries. In 2019, 99% of the world's population lived in areas that did not meet the World Health Organization's (WHO) air quality guidelines. Ambient air pollution, both in cities and rural areas, is linked to an estimated 4.2 million premature deaths annually worldwide. It is caused by fine particulate matter, which leads to cardiovascular and respiratory diseases and cancers.

Communities of colour are disproportionately impacted by unhealthy air and face higher risks of associated health issues. Research has revealed that racial and ethnic disparities in pollutant-linked diseases, such as asthma, have increased over the last decade. Communities of colour experience higher rates of pediatric asthma and premature mortality due to pollutants compared to predominantly white communities. For instance, a study found that Hispanics, Asians, and especially Blacks, had a higher risk of premature death from particle pollution than whites.

The reasons for this disparity are rooted in systemic racism and discriminatory housing policies. Historically, redlining and racial segregation have resulted in communities of colour being located near factories, congested roadways, or shipping routes with heavily polluted air. This proximity to pollution sources increases their exposure to harmful pollutants, such as nitrogen dioxide and fine particulate matter. Fine particulate matter can penetrate deep into the lungs and enter the bloodstream, leading to heart disease, lung cancer, and stroke.

Additionally, low socioeconomic status, lack of access to healthcare, and higher exposure to traffic further contribute to the higher vulnerability of communities of colour. They may also be more likely to live in counties with higher pollution levels and experience higher rates of chronic conditions, such as diabetes and heart disease, which make them more susceptible to the health impacts of air pollution.

Addressing these disparities requires place-based policies that allocate resources and targeted actions to historically overburdened communities. It is essential to implement regulations that effectively address environmental injustice and reduce key sources of ambient air pollution, such as cleaner transport, energy-efficient homes, and better waste management practices.

Air pollution is a leading cause of health complications and mortality worldwide, especially affecting lower-income groups

Air pollution is a major environmental health hazard and a leading cause of health complications and mortality worldwide. It is responsible for more than 6.5 million deaths each year globally, a number that has increased over the past two decades. The World Health Organization (WHO) estimates that in 2019, ambient (outdoor) air pollution in both cities and rural areas caused 4.2 million premature deaths worldwide per year due to exposure to fine particulate matter, resulting in cardiovascular and respiratory disease, strokes, heart diseases, lung cancer, and acute and chronic respiratory diseases. The combined effects of ambient and household air pollution are associated with 6.7 million premature deaths annually.

Outdoor air pollution is a major environmental health problem affecting everyone in low-, middle-, and high-income countries. However, it disproportionately affects people in low- and middle-income countries, with 89% of premature deaths occurring in these areas. Lower-income groups tend to be more exposed and vulnerable to the health risks of air pollution due to limited access to healthcare and their reliance on polluting, low-cost fuels for cooking and lighting. According to a study, 716 million of the world's lowest-income people live in areas with unsafe levels of air pollution, especially in Sub-Saharan Africa.

Several factors affect an individual's level of risk from air pollution. These include exposure, susceptibility, and access to healthcare. Where someone lives, goes to school, or works significantly impacts their exposure to air pollution. Higher exposure generally leads to a greater risk of harm. Certain groups, such as children, older adults, pregnant individuals, and people with chronic conditions, especially heart and lung diseases, are more susceptible to the adverse health effects of air pollution.

The sources of outdoor air pollution include residential energy for cooking and heating, vehicles, power generation, agriculture/waste incineration, and industry. Policies and investments that support sustainable land use, cleaner household energy, cleaner transport, energy-efficient housing, improved power generation, better waste management, and access to clean household energy can effectively reduce key sources of ambient air pollution. The WHO has developed strategies to raise awareness about the risks of air pollution and promote interventions and initiatives for healthy sectoral policies to address the issue.

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