Health Impact Of Air Pollution: Who's Assessment

Air pollution is a major environmental risk to health, and it is caused by the presence of contaminants in the atmosphere, such as dust, fumes, gas, mist, odour, smoke or vapour. These pollutants can cause inflammation, oxidative stress, immunosuppression, and mutagenicity in cells throughout the body, impacting the lungs, heart, and brain, among other organs, and ultimately leading to disease. To address this issue, the World Health Organization (WHO) has developed AirQ+, a software tool that enables users to quantify the health burden and impact of air pollution. AirQ+ utilizes methodologies to assess the impacts of short- and long-term exposure to ambient air pollution, helping users understand the relationship between air pollution and mortality risks. By providing these tools and supporting decision-makers, WHO plays a crucial role in promoting health and reducing the disease burden associated with air pollution.

Software tools like AirQ+ can quantify the health burden and impact of air pollution

Air pollution is a major environmental risk to health, causing various diseases, including stroke, heart disease, lung cancer, and respiratory issues such as asthma. To address this critical issue, the World Health Organization (WHO) has developed software tools, including AirQ+, to quantify the health burden and impact of air pollution.

AirQ+ is a powerful tool that enables users to perform calculations and assess the health effects of exposure to air pollution. It provides estimates of the reduction in life expectancy due to significant air pollutants, helping to address critical questions in policy discussions. The software includes methodologies to evaluate the impacts of both short- and long-term exposure to ambient air pollution. These methodologies are based on epidemiological cohort studies that establish a relationship between long-term air pollution concentration levels and mortality risks in exposed populations.

One of the key advantages of AirQ+ is its ability to handle diverse data inputs. Users can load their own data for pollutants not included in the pre-loaded datasets, ensuring a comprehensive analysis. This flexibility allows for the assessment of acute health risks, as demonstrated in China, where AirQ+ was applied to quantify the health outcome of the exposed population compared to a reference concentration. Additionally, AirQ+ provides relative risks (RRs) for selected pollutant health endpoints, conversion factors between PM2.5 and PM10 at the national level, and worldwide solid fuel use statistics.

The software is user-friendly and accessible, available in multiple languages, including English, French, German, Russian, and Spanish. Since its launch in 2016, AirQ+ has been downloaded by over 1000 users from 112 countries and utilized in more than 300 cities. It is recommended that AirQ+ be used with the support of an epidemiologist or air pollution impact assessment expert to ensure accurate analysis and interpretation of results.

As a tool for health impact assessment (HIA), AirQ+ plays a crucial role in helping decision-makers and member states make informed choices. HIA is a consolidated approach that estimates and anticipates the health consequences of policies, plans, and projects, promoting health opportunities and preventing disease or injury. By using AirQ+, policymakers can evaluate the potential health impact of interventions aimed at reducing air pollution and make evidence-based decisions to improve public health.

Air pollution is an environmental risk to health, causing diseases like stroke, heart disease, lung cancer, and respiratory diseases

Air pollution is a significant environmental risk to health, causing and contributing to a range of diseases and health conditions, including stroke, heart disease, lung cancer, and respiratory diseases.

The health effects of air pollution exposure have been quantified by the World Health Organization (WHO) through their software tool, AirQ+. This tool calculates the health implications of air pollution, including the reduction in life expectancy, and provides risk estimates for both short-term and long-term exposures.

One of the most well-known impacts of air pollution on health is its contribution to respiratory diseases. High levels of nitrogen dioxide (NO2) and sulphur dioxide (SO2) can irritate the lining of airways, causing inflammation and making it harder to breathe. This can lead to coughing, tightness of the chest, and increased hospital admissions for people with asthma, chronic obstructive pulmonary disease (COPD), and other lung conditions. Older people and those with pre-existing lung conditions are particularly vulnerable to the effects of air pollution.

Air pollution has also been linked to an increased risk of cardiovascular diseases, including heart disease and stroke. Fine particulate matter, known as PM2.5, can infiltrate the bloodstream and impact the health of the heart and blood vessels. Studies have found a strong association between air pollution and cardiovascular diseases, with the ubiquitous nature of exposure to air pollution posing a significant public health risk.

Additionally, air pollution is a contributing factor to lung cancer. The International Agency for Research on Cancer (IARC) has classified outdoor air pollution and particulate matter with an aerodynamic diameter of less than 2.5 microns (PM2.5) as carcinogenic to humans. These fine particles can reach the breathing sacs in the lungs and carry toxic chemicals linked to cancer. While smoking tobacco is a significant cause of lung cancer, the combination of smoking and air pollution has a synergistic effect, increasing the risk of lung cancer and reducing survival rates.

Fine particulate matter, carbon monoxide, and ozone are among the most harmful pollutants

Particulate matter (PM) refers to inhalable particles composed of sulphate, nitrates, ammonia, sodium chloride, black carbon, mineral dust, or water. PM can vary in size and is generally defined by its aerodynamic diameter, with PM2.5 and PM10 being the most common in the regulatory framework and relevant for health. PM2.5, which comprises a portion of PM10, has particles small enough to get into the deep parts of the lungs or even the bloodstream. Short-term exposure to PM2.5 has been linked to premature mortality, increased hospital admissions for heart or lung causes, acute and chronic bronchitis, asthma attacks, and respiratory symptoms. Long-term exposure to PM2.5 has been associated with cardiovascular health effects and premature mortality.

Carbon monoxide (CO) is another harmful pollutant. It is a colorless, odorless, and toxic gas that can have serious health effects, even at low concentrations. Carbon monoxide is produced by the incomplete combustion of fossil fuels, such as in vehicle emissions and industrial processes. It can also be emitted from natural sources such as wildfires. Exposure to carbon monoxide can lead to headaches, dizziness, confusion, nausea, and even death in extreme cases.

Ground-level ozone (O3) is the third pollutant and is a major component of smog. It is formed from photochemical reactions with pollutants such as volatile organic compounds, carbon monoxide, and nitrogen oxides emitted from vehicles and industry. Ozone is a highly reactive gas that can irritate the eyes, nose, throat, and lungs, even at low levels. Ground-level ozone is of particular concern as it is formed close to the Earth's surface, where people live and breathe.

The health impact of these pollutants is significant, and reducing their levels in the air can help decrease the burden of diseases such as stroke, heart disease, lung cancer, and respiratory illnesses, including asthma. Tools such as AirQ+ developed by WHO/Europe can be used to quantify the health effects of exposure to these pollutants and aid in decision-making to improve air quality and public health.

Maternal exposure to air pollution is associated with adverse birth outcomes

Air pollution is a major environmental risk to health. By reducing air pollution levels, countries can reduce the burden of disease from stroke, heart disease, lung cancer, and both chronic and acute respiratory diseases, including asthma. WHO/Europe's software tool AirQ+ is used to quantify the health effects of exposure to air pollution, including estimates of the reduction in life expectancy, for the most significant air pollutants.

A study in the US state of Kansas from 2000 to 2015 investigated the connections between three ambient air pollutants (nitrogen dioxide (NO2), particulate matter with an aerodynamic diameter of less than 2.5 μm (PM2.5), and ozone (O3)) and two birth outcomes (preterm birth and birth weight) and two pregnancy complications (gestational diabetes mellitus (GDM) and gestational hypertension (GH)). The results showed conflicting evidence on the effects of air pollution on birth outcomes and pregnancy complications, with variations in population, study design, exposure measurement, and GDM diagnosis.

Another study in Durban, South Africa, from 2013 to 2017 examined the impact of ambient air pollution exposure during pregnancy on adverse birth outcomes among pregnant women in the Mother and Child in the Environment (MACE) birth cohort. The results indicated that exposure to PM2.5 had significant direct and indirect effects on the risk of all adverse birth outcomes. Additionally, increased levels of maternal exposure to SO2 during pregnancy were associated with an increased probability of the infant being small for gestational age.

These studies highlight the potential impacts of maternal exposure to air pollution on adverse birth outcomes. It is crucial for local governments to implement effective measures to control air pollution and for healthcare providers to educate pregnant women about the risks associated with air pollution exposure during pregnancy.

Air pollution impacts can be assessed when evaluating the consequences of policies and interventions

Air pollution is a critical environmental risk to health, and it is caused by the presence of contaminants in the atmosphere, such as dust, fumes, gas, mist, odour, smoke, or vapour. These pollutants can enter the body through the respiratory tract, leading to inflammation, oxidative stress, immunosuppression, and mutagenicity in cells, impacting various organs, including the lungs, heart, and brain.

The World Health Organization (WHO) has developed tools to support decision-making on air pollution and to promote health initiatives. One such tool is AirQ+, a software tool that enables the quantification of the health burden and impact of air pollution. AirQ+ utilizes methodologies to assess the consequences of both short- and long-term exposure to ambient air pollution, drawing on evidence from epidemiological cohort studies. These studies establish a link between long-term air pollution concentration levels and mortality risks in exposed populations. By employing AirQ+, decision-makers can evaluate the potential outcomes of policies, interventions, or hypothetical scenarios related to air quality.

AirQ+ provides calculations and estimates related to the health effects of air pollution exposure. It offers insights into the reduction in life expectancy associated with significant air pollutants and helps assess the impacts of short-term changes in air quality. Additionally, it facilitates the examination of long-term exposures using a life-tables approach, which is based on risk estimates from cohort studies. AirQ+ is available in multiple languages, including English, French, German, Russian, and Spanish, and has been downloaded by users from over 100 countries, demonstrating its global reach and applicability.

The use of AirQ+ is recommended in conjunction with the expertise of an epidemiologist or air pollution impact assessment specialist. The software comes with manuals that cater to different levels of expertise, ensuring that users can effectively analyze the impact of air pollution on public health. By utilizing AirQ+, decision-makers can make informed choices, considering the potential health consequences of various scenarios related to air pollution. This tool empowers policymakers to implement interventions and strategies that effectively mitigate the health risks associated with air pollution, ultimately improving public health outcomes.

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