Define air pollution

Air pollution is one of the world’s largest health and environmental problems. It develops in two contexts: indoor (household) air pollution and outdoor air pollution. We look in detail at the data and research on the health impacts of Indoor Air Pollution, attributed deaths, and its causes across the world in our full entry: We look in detail at how exposure to Outdoor Air Pollution, its health impacts and attributed deaths across the world in our full entry: In this entry we look at the aggregate picture of air pollution – both indoor and outdoor. • Absolute number of deaths from ambient particulate air pollution • Air pollutant emissions • Air pollution deaths as percentage of global disease burden • Air pollution deaths from fossil fuels • Air pollution in London vs. Delhi • Air pollution vs. GDP per capita • Death rate from air pollution • Death rate from air pollution By type, line chart • Death rate from air pollution By type, stacked area • Death rate from ambient particulate air pollution Age-standardized • Death rate from ambient particulate air pollution vs. GDP per capita • Death rate from outdoor air pollution in 1990 vs. 2019 • Death rate from outdoor air pollution vs GDP per capita • Death rate from ozone pollution • Death rate from ozone pollution age-standardized • Death rate from particular matter air pollution vs PM2.5 concentration • Deaths attributed to air pollution from fossil fuels and deaths due to terrorism • Deaths from air pollution • Deaths fro...

As people seek ways to stay safe, it is important to understand how the air quality index, or AQI, works. The color-coded system measures the air quality in relation to certain pollutants and the associated health risks at various levels. Here is a breakdown of the AQI, the different color codes used and what you should do to What is AQI? The air quality index, or How does AQI work? The AQI is The EPA determines the AQI values based on • Ground-level ozone • Particle pollution (also known as particulate matter) • Carbon monoxide • Sulfur dioxide • Nitrogen dioxide According to the National Weather Service, The AQI is measured in six levels: • 0 to 50 • 51 to 100 • 101 to 150 • 151 to 200 • 201 to 300 • 301 and higher Each has a different "level of concern" in relation to the air pollutants. It ranges from "good" to "hazardous." This is based on how someone would be affected after breathing in polluted air for a few hours or days. Each level is also assigned a corresponding color, with green representing "good" ranging to maroon representing "hazardous." If the AQI values are at or are below 100, air quality is generally deemed as satisfactory. However, once the AQI goes above that value, it is unhealthy. This impacts certain sensitive groups of people first, but will affect everyone as the AQI values increase. Canada is on fire. Breaking down AQI values and what they mean 0-50: Code green air is deemed " 51-100: Code yellow air is considered " 101-150: Once the air quality...

Air pollution consists of chemicals or particles in the air that can harm the health of humans, animals, and plants. It also damages buildings. Pollutants in the air take many forms. They can be gases, solidparticles, or liquid droplets. Sources of Air Pollution Pollution enters the Earth's atmosphere in many different ways. Most air pollution is created by people, taking the form of emissions from factories, cars, planes, or aerosol cans. Second-hand cigarette smoke is also consideredair pollution. These man-made sources of pollution are called anthropogenic sources. Some types of air pollution, such as smoke from wildfires or ash from volcanoes, occur naturally. These are called natural sources. Air pollution is most common in large cities where emissions from many different sources are concentrated. Sometimes, mountains or tall buildings prevent air pollution from spreading out. This air pollution often appears as a cloud making the air murky. It is called smog. The word "smog" comes from combining the words "smoke" and " fog." Large cities in poor and developing nations tend to have more air pollution than cities in developed nations. According to the World Health Organization (WHO), some of the worlds most polluted cities are Karachi, Pakistan; New Delhi, India; Beijing, China; Lima, Peru; and Cairo, Egypt. However, many developed nations also have air pollution problems. Los Angeles, California, is nicknamed Smog City. Indoor Air Pollution Air pollution is usually th...

A general view showing buildings shrouded by polluted air in Seoul on April 12, 2023. Jung Yeon-Je/AFP via Getty Images This week, Canada and parts of the United States have confronted unprecedented declines in air quality due to smoke from Canadian wildfires, but people elsewhere in the world have long had to adjust and adapt to living with hazardous pollution levels. In some cases, those levels have improved over time. NPR correspondents Anthony Kuhn and Eyder Peralta and freelance reporters Shalu Yadav and Kate Bartlett share what it's like in Beijing, Seoul, New Delhi, Mexico City and Johannesburg. From Beijing to Seoul I first visited Beijing in 1982, and lived there much of the time between 1992 and 2018. In most of my years there, the pollution was terrible, especially in winter, although we didn't have ways to measure it. The air had an acrid, sulfurous smell, and soot was everywhere. To me, it was simply the cost of covering — and living — an epic story. People were less aware than they are now of the difference between weather and pollution, fog and smog. Ahead of the 2008 Olympics, Beijing started to get rid of the coal stoves commonly used in the courtyard dwellings ("siheyuan" in Chinese) of Beijing's old city, and coal-fired heating plants, to help clean up the air ahead of the Games. Factories were moved farther and farther out of the city center. Coal-burning stoves in the courtyards were slowly replaced by electric heat. While air quality in Beijing has im...