Air Pollution: Who's Global Report

Air pollution is one of the biggest health and environmental problems in the world, with almost 100% of the global population exposed to air pollution levels that put them at increased risk of diseases including heart disease, stroke, lung cancer, and pneumonia. The World Health Organization (WHO) has developed guidelines on clean fuels and technologies for household cooking, heating, and lighting, and monitors exposure levels and health impacts at the national, regional, and global levels. WHO data shows that 99% of the global population breathes air that exceeds the recommended guideline limits and contains high levels of pollutants, with low- and middle-income countries suffering the highest exposures. Air pollution is a health and environmental issue across all countries, but with large differences in severity.

Indoor air pollution

The World Health Organization (WHO) has been actively addressing the issue of indoor air pollution and its impact on health. They have developed guidelines for indoor air quality and household fuel combustion, offering recommendations on clean fuels and technologies. These guidelines, known as the "Guidelines for Indoor Air Quality: Household Fuel Combustion," provide evidence-based advice on the types of fuels and technologies that can be considered clean and protect health. WHO defines clean fuels and technologies as solar, electricity, biogas, liquefied petroleum gas (LPG), natural gas, alcohol fuels, and biomass stoves that meet emission targets.

To support the transition to cleaner household fuels and technologies, WHO also builds capacity at the country and regional levels through direct consultations and workshops on household energy and health. They maintain a global household energy database to monitor progress and report on the proportion of the population relying primarily on clean fuels and technologies. Additionally, WHO provides tools and resources to help countries develop clean household energy policies and programs, including a planning tool that calculates the costs and benefits of transitioning to cleaner household energy options.

The effects of indoor air pollution on health can be both immediate and long-term. Irritation of the eyes, nose, and throat, headaches, dizziness, and fatigue are some of the immediate symptoms that are usually short-term and treatable. Prolonged exposure to indoor air pollutants can lead to more severe health issues, including respiratory diseases, heart disease, and cancer. Women and children, who typically spend more time near the domestic hearth and are responsible for household chores such as cooking and collecting firewood, bear the greatest health burden from indoor air pollution caused by the use of polluting fuels and technologies.

Outdoor air pollution

The health impacts of outdoor air pollution are significant, with an estimated 4.2 million premature deaths worldwide in 2019 attributed to this type of pollution. The mortality is primarily due to exposure to fine particulate matter, which causes cardiovascular and respiratory diseases, and cancers. According to WHO estimates, 68% of outdoor air pollution-related premature deaths in 2019 were due to ischaemic heart disease and stroke, 14% were due to chronic obstructive pulmonary disease, 14% were due to acute lower respiratory infections, and 4% were due to lung cancers.

WHO plays a crucial role in addressing outdoor air pollution by supporting countries through evidence-based policies and actions. The organization's Air Quality and Health Unit works in three key areas: knowledge, evidence, and measuring progress. Additionally, WHO provides technical support to its member states in developing normative guidance, tools, and authoritative advice on health issues related to air pollution.

To reduce outdoor air pollution, policies and investments supporting cleaner transport, energy-efficient homes, power generation, industry, and better municipal waste management are essential. These interventions can effectively decrease key sources of outdoor air pollution and improve air quality globally.

Various tools and resources are available to monitor outdoor air pollution levels, including interactive maps that display real-time air quality data for different countries and regions. These maps utilize laser particle sensors to measure PM2.5 and PM10 particle pollution, which are among the most harmful pollutants.

Health impacts

Air pollution is the presence of contaminants in the atmosphere, such as dust, fumes, gas, mist, odour, smoke or vapour, in quantities that can be harmful to human health. It is the single largest environmental health risk and is responsible for an estimated seven million premature deaths worldwide every year.

The health impacts of air pollution depend on the types, sources and concentrations of the pollutants in the mixture to which an individual is exposed. The main pathway of exposure is through the respiratory tract, but almost every organ in the body can be impacted. Pollutants can enter the bloodstream via the lungs and circulate throughout the body, leading to systemic inflammation and carcinogenicity. Fine particulate matter (PM2.5) is the air pollutant driving the most significant health problems and premature mortality.

Short- and long-term exposure to air pollution can lead to a wide range of diseases, including stroke, heart disease, chronic obstructive pulmonary disease, pneumonia, trachea, bronchus and lung cancers, aggravated asthma, lower respiratory infections, type 2 diabetes, obesity, Alzheimer's disease, dementia, and kidney disease. Long-term exposure to fine particulate matter increases a person's risk for diseases with a longer onset, such as noncommunicable diseases. Maternal exposure to air pollution is also associated with adverse birth outcomes, such as low birth weight, pre-term birth and small for gestational age births.

Children, the elderly, pregnant women, and those with pre-existing health conditions are more susceptible to air pollution-related diseases. Genetics, comorbidities, nutrition, and sociodemographic factors also impact a person's susceptibility. In Europe, there is strong evidence linking lower socioeconomic status to increased exposure to air pollution. Poorer people are more likely to live next to busy roads or industrial areas and thus face higher levels of exposure.

Real-time air quality monitoring

The World Health Organization (WHO) plays a crucial role in monitoring air pollution exposure and its health impacts at the national, regional, and global levels. WHO's Air Pollution Data Portal provides valuable resources, such as Burden of Disease statistics, air quality databases, and modelled exposure estimates for both ambient and household air pollution.

To facilitate real-time air quality monitoring, various organizations and companies have developed interactive maps and monitoring solutions. For instance, WAQI.info offers a real-time air pollution map for over 80 countries, utilizing the GAIA air quality monitor, which employs laser particle sensors to measure PM2.5 and PM10 particle pollution. This monitor is easy to set up and provides instant access to real-time air pollution data.

PurpleAir is another notable provider of real-time air quality monitoring solutions. Their industry-leading sensors measure particulate pollution (PM2.5), temperature, humidity, and pressure, offering accurate and affordable options for individuals and organizations alike. PurpleAir sensors have been deployed in schools, empowering students to learn about air pollution and make healthier choices.

Additionally, interactive maps like AirNow.gov provide current air quality information for specific locations, utilizing data from various sources, including AirNow, the Western Regional Climate Center, AirSis, and PurpleAir. These maps allow users to search for geographic or location-based information, offering a comprehensive view of air quality in different areas.

Mitigating risks

Air pollution is one of the most significant health and environmental problems worldwide, causing around 7 million premature deaths annually. It is a combination of outdoor and indoor particulate matter and ozone, which leads to various diseases and health issues, including heart disease, stroke, lower respiratory infections, lung cancer, diabetes, and chronic obstructive pulmonary disease (COPD). The World Health Organization (WHO) has reported that almost the entire global population (99%) breathe air that exceeds its guideline limits and contains high levels of pollutants. The burden of air pollution is generally higher in low- and middle-income countries due to indoor pollution caused by solid fuel use and increased outdoor pollution during industrialization.

To mitigate the risks associated with air pollution, the following strategies can be implemented:

• Promote Sustainable Land Use: Policies that support sustainable land use can help reduce outdoor air pollution. This includes implementing measures to reduce deforestation, encouraging afforestation, and promoting sustainable agricultural practices that minimize the use of harmful chemicals and reduce the need for waste incineration.
• Support Cleaner Household Energy: Providing access to clean and affordable household energy sources is crucial. This can include promoting the use of clean cooking technologies, such as improved stoves or electric cookers, instead of open fires or simple stoves fueled by kerosene, biomass, or coal.
• Improve Transport and Energy Efficiency: Investments in cleaner and more sustainable transport options, such as electric or hydrogen-powered vehicles, can significantly reduce air pollution from motor vehicles. Additionally, encouraging the use of public transportation, carpooling, and active travel options like walking and cycling can help decrease vehicle emissions.
• Enhance Industrial and Power Generation Processes: Industries and power plants should adopt cleaner technologies and best practices to minimize emissions. This includes investing in renewable energy sources like solar, wind, and hydropower, as well as implementing stricter emission standards and regulations for fossil fuel-based power generation.
• Strengthen Municipal Waste Management: Effective waste management strategies can reduce air pollution caused by waste incineration. This involves improving waste collection and disposal systems, promoting recycling and composting, and implementing safe and environmentally friendly waste treatment technologies.
• Raise Awareness and Education: Educating communities about the risks of air pollution and the actions they can take to improve air quality is essential. This includes raising awareness about the health impacts of air pollution, promoting the use of cleaner technologies, and encouraging individuals to advocate for policies that support sustainable practices and reduce air pollution.
• Implement Air Quality Monitoring and Regulations: Governments and local authorities should monitor air quality regularly and enforce regulations to limit emissions. This includes setting standards for acceptable pollutant levels and imposing penalties on industries or sectors that exceed these limits.
• International Collaboration: Air pollution is a global issue that requires international cooperation. Sharing best practices, technologies, and resources among countries can help develop effective strategies to combat air pollution on a larger scale.

By implementing these strategies and continuing to monitor the impact of air pollution on human health and the environment, we can effectively mitigate the risks associated with air pollution and improve the overall health and well-being of populations worldwide.

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