How to Reduce Risks of Bad Air Quality
2025-02-27
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1Air quality differs from place to place and day to day.
2But about 99 percent of the world's population breathes air at some point that does not meet pollution guidelines set by the World Health Organization (WHO).
3Different forms of air pollution kill about 7 million people each year, the U.N. health agency estimates.
4But health experts say there are some actions individuals can take to protect themselves, even in the world's most polluted cities.
5The first step is to start with the understanding that air is not only polluted when it looks smoky or smoggy, said Tanushree Ganguly.
6She is an air quality expert with the Energy Policy Institute of Chicago's India program.
7"Blue skies can't guarantee you clean air," Ganguly told The Associated Press.
8Air pollutants often come from people burning things.
9Examples include fuels as well as clearing operations involving crops or trees.
10Pollutants can also be released from wildfires.
11Among the most dangerous particles we can breathe in are called particulate matter.
12The smallest of these are known as PM 2.5.
13This is because they are less than 2.5 microns in diameter.
14These particles can travel deep inside human lungs and are mostly created by burning fuels.
15Larger particles, known as PM 10, are linked to agriculture, roadways, mining or wind-blown dust.
16Other dangerous pollutants include gases like nitrogen dioxide or sulfur dioxide, which are also produced from burning fuels.
17This information comes from Anumita Roychowdhury, an air pollution expert at the Center for Science and Environment in New Delhi.
18The American-based Health Effects Institute says air pollution is the second-largest risk factor for early death worldwide, behind high blood pressure.
19Short-term exposure can cause asthma attacks and increase the risk of heart attacks and stroke, especially in older people and those with existing medical problems.
20Long-term exposure can cause serious heart and lung problems that can lead to death.
21A recent study by the U.N. children's agency UNICEF found that more than 500 million children in East Asia and Pacific countries breathe unhealthy air.
22The pollution is linked to the deaths of 100 children under age 5 every day.
23June Kunugi, UNICEF's Regional Director for East Asia, said the polluted air limits growth, harms lungs and affects thinking abilities.
24"Every breath matters, but for too many children every breath can bring harm," she said.
25Over 6,000 cities in 117 countries now record and follow air quality levels.
26Many mobile apps include air quality information as well.
27But it can be difficult to know how bad the air is by looking at these numbers.
28To help people better understand air quality levels, many countries have established an air quality index, or AQI.
29Larger numbers on this index mean worse air.
30Different countries have different air quality standards.
31For example, India's daily PM 2.5 limit is more than 1.5 times higher than in Thailand and 4 times higher than WHO standards.
32For individuals, experts say the goal should be to limit exposure when air quality is bad, by staying indoors or wearing a mask.
33This is not always possible, though.
34Danny Djarum is with the World Resources Institute.
35He told the AP there are many people who live or work outside and "can't really afford" to stay indoors.
36People also need to watch indoor air pollution that can be caused by common household activities like cooking or burning incense.
37While air purifiers can help reduce indoor air pollution, experts say they do have limitations.
38The devices work by pulling air from a room and then pushing it through a filter that traps pollutants.
39The filtered air is then sent back into the room.
40Air purifiers work best when used in small spaces and when people are nearby.
41This is because they can only clean a certain amount of air, said Rajasekhar Balasubramanian of the National University of Singapore.
42He added, "If we have a tiny air purifier in a large room, it won't be effective."
43I'm John Russell.
44And I'm Caty Weaver.
1Air quality differs from place to place and day to day. But about 99 percent of the world's population breathes air at some point that does not meet pollution guidelines set by the World Health Organization (WHO). 2Different forms of air pollution kill about 7 million people each year, the U.N. health agency estimates. But health experts say there are some actions individuals can take to protect themselves, even in the world's most polluted cities. 3The first step is to start with the understanding that air is not only polluted when it looks smoky or smoggy, said Tanushree Ganguly. She is an air quality expert with the Energy Policy Institute of Chicago's India program. 4"Blue skies can't guarantee you clean air," Ganguly told The Associated Press. 5Pollutants and their sources 6Air pollutants often come from people burning things. Examples include fuels as well as clearing operations involving crops or trees. Pollutants can also be released from wildfires. 7Among the most dangerous particles we can breathe in are called particulate matter. The smallest of these are known as PM 2.5. This is because they are less than 2.5 microns in diameter. These particles can travel deep inside human lungs and are mostly created by burning fuels. Larger particles, known as PM 10, are linked to agriculture, roadways, mining or wind-blown dust. 8Other dangerous pollutants include gases like nitrogen dioxide or sulfur dioxide, which are also produced from burning fuels. This information comes from Anumita Roychowdhury, an air pollution expert at the Center for Science and Environment in New Delhi. 9Health effects 10The American-based Health Effects Institute says air pollution is the second-largest risk factor for early death worldwide, behind high blood pressure. 11Short-term exposure can cause asthma attacks and increase the risk of heart attacks and stroke, especially in older people and those with existing medical problems. Long-term exposure can cause serious heart and lung problems that can lead to death. 12A recent study by the U.N. children's agency UNICEF found that more than 500 million children in East Asia and Pacific countries breathe unhealthy air. The pollution is linked to the deaths of 100 children under age 5 every day. June Kunugi, UNICEF's Regional Director for East Asia, said the polluted air limits growth, harms lungs and affects thinking abilities. 13"Every breath matters, but for too many children every breath can bring harm," she said. 14How to tell if air is safe? 15Over 6,000 cities in 117 countries now record and follow air quality levels. Many mobile apps include air quality information as well. But it can be difficult to know how bad the air is by looking at these numbers. 16To help people better understand air quality levels, many countries have established an air quality index, or AQI. Larger numbers on this index mean worse air. 17Different countries have different air quality standards. For example, India's daily PM 2.5 limit is more than 1.5 times higher than in Thailand and 4 times higher than WHO standards. 18How can you protect yourself? 19For individuals, experts say the goal should be to limit exposure when air quality is bad, by staying indoors or wearing a mask. This is not always possible, though. Danny Djarum is with the World Resources Institute. He told the AP there are many people who live or work outside and "can't really afford" to stay indoors. 20People also need to watch indoor air pollution that can be caused by common household activities like cooking or burning incense. 21What are the benefits - and limitations - of air purifiers? 22While air purifiers can help reduce indoor air pollution, experts say they do have limitations. The devices work by pulling air from a room and then pushing it through a filter that traps pollutants. The filtered air is then sent back into the room. 23Air purifiers work best when used in small spaces and when people are nearby. This is because they can only clean a certain amount of air, said Rajasekhar Balasubramanian of the National University of Singapore. He added, "If we have a tiny air purifier in a large room, it won't be effective." 24I'm John Russell. 25And I'm Caty Weaver. 26Aniruddha Ghosal reported on this story for the Associated Press. John Russell adapted it for VOA Learning English. 27_______________________________________________________ 28Words in This Story 29smog - n. a kind of air pollution that can consist of smoke, gases, chemicals, etc. 30factor - n. something that contributes to the production of a result 31expose - v. to subject to risk from a harmful condition 32asthma - n. a kind of a chronic lung disorder 33standard - n. something established by authority as a rule for the measure of quality 34afford - v. to be able to pay for 35incense - n. a kind of material used to produce a pleasant smell when burned 36filter - n. to pass a liquid or gas through a piece of equipment in order to remove solid pieces or other substances