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Air pollution shortens human lives by more than a year, according to a new study from a team of leading environmental engineers and public health researchers. Better air quality could
lead to a significant extension of lifespans (寿命)around the world.
It is the first time that data on air pollution and the lifespan has been studied together in
order to check how air pollution affects overall life expectancy.
The researchers looked at outdoor air pollution from particulate matter(PM) (颗粒物) smaller than 2.5 microns. These particulates can enter deep into the lungs, and breathing PM 2.5 is associated with the increased risk of heart attacks, strokes and cancer. PM 2.5 pollution comes from power plants, cars and trucks, fires, agriculture and industrial emissions(排放物) .
Led by Joshua Apte, the team used data from the Global Burden of Disease Study to measure PM 2.5 air pollution exposure and its consequences in 185 countries. They then quantified the national impact on life expectancy for each individual country as well as on a global scale.
"The fact that air pollution is a major global killer is already well-known," said Apte,"And we all care about how long we can live. Here, we were able to systematically identify how air pollution shortens lives around the world. What we found is that air pollution has a very large effect on survival—on average about a year globally."
In the context of other significant phenomena negatively affecting human survival rates, Apte said this is a big number."For example, it's considerably larger than the benefit in survival we might see if we found cures for both lung and breast cancer combined,"he said. "In countries like India and China, the benefit for elderly people of improving air quality would be especially large. For much of Asia, if air pollution were removed as a risk for death, 60-year-olds would have a 15 percent to 20 percent higher chance of living to age 85 or older.”
14.What do we know about PM 2.5?
A. People's heath suffer a lot from it.
B. It will be controlled in the future.
C. It mainly comes from industrial emissions.
D. It spreads to the world from Asian countries.
15.What did the researchers do to study how air pollution affects the lifespan?
A. They collected accurate information from all the Asian countries.
B.They employed the research data to calculate the effect.
C. They studied the disease and lifespan together time and time again.
D.They measured particulate matter much more carefully than before.
16.What can be inferred from the text?
A.The key to people living longer is good air quality.
B. People think air pollution is the most dangerous killer to them.
C.Apte will agree that people should take action to treat air pollution.
D. Factories should decrease the production of cars to stop air pollution.
17.What is the best title for the text?
A.The way human beings enjoy a longer lifespan
B.The importance of getting rid of air pollution
C.Asian people are suffering from serious air pollution
D. Air pollution reduces the lifespan by more than one year
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