VOA慢速英语--研究发现空气污染会增加中老年人患病入院几率

Older adults who breathe in very small particles from air pollution for even a day or two are more likely to be hospitalized for many diseases, a recent U.S. study suggests.

Researchers examined particles called PM2.5, a mixture of solid particles and liquid. The particles are too small for the eye to see; each one is about three percent of the size of a human hair or smaller.

PM2.5 can include dust, dirt, soot¹ and smoke.

The researchers confirmed earlier links between short-term exposure to PM2.5 and a higher risk of hospitalization and death from some diseases. Those include heart and lung diseases, diabetes² and blood flow blockages³ in the legs. They also found new links between short-term exposure and more hospitalizations for things like kidney failure and sepsis. Sepsis is a life-threatening illness caused by blood infections.

The study team examined hospital records for Medicare patients around the United States from 2000 to 2012. The researchers chose patients based on their home zip codes.

They looked at data on air pollution levels the day before and day of each patient's hospitalization. The study included 214 different health conditions.

Yaguang Wei is an environmental health researcher at Harvard T.H. Chan School of Public Health in Boston, Massachusetts. He is also the lead writer of the study.

Wei said the most common and dangerous health effects of PM2.5 exposure have been heart and breathing diseases. These are "the leading causes of hospitalization, emergency room visits and even death," he said.

The World Health Organization, or WHO, released air quality guidelines in 2005. The guidelines say people should not be exposed to average PM2.5 levels above 25 micrograms per cubic meter of air for more than 24 hours.

Few studies have looked at the connection between short-term exposure to fine particulate⁴ matter and conditions such as sepsis, fluid disorders⁵, kidney failure and intestinal⁶ problems.

For such diseases, each cubic meter rise in short-term average fine PM levels was linked with a yearly rise of around 2,050 hospital visits. That cost $31 million in hospital visits, plus costs for care afterward⁷.

Even air pollution levels below safety levels set by the WHO were linked with a higher risk of hospitalizations for conditions such as heart and breathing disorders. These diseases have been tied in earlier studies to PM2.5 exposure.

For these diseases, each cubic meter rise in short-term average fine PM levels was linked with a yearly rise of around 3,642 hospital visits. That cost $69 million in hospital visits, plus costs for care afterward.

Wei and the team of researchers reported their findings in The BMJ medical journal.

Costs related to short-term air pollution exposure are probably far higher than the research suggests, said study co-writer Francesca Dominici. She is also a public health researcher at Harvard.

In an email to Reuters Health, she said the major limit of this study was that costs following hospital visits were not well documented.

People may not be able to avoid exposure to air pollution, but they can still do things to protect themselves, said Matthew Loxham. He is with the University Hospital Southampton in the United Kingdom.

Loxham said in an email that everyone should pay attention to local air quality levels and guidance. But people with heart conditions, asthma⁸, lung disease and other illnesses should pay special attention. Local guidance on poor air quality days may, for example, tell people with such conditions to close windows or avoid some kinds of outdoor exercise.

And, Loxham said, patients and doctors should take note of how poor air quality can worsen health conditions to better understand and treat them.

Words in This Story

expose – v. to leave (something) without covering or protection

soot – v. a black powder that is formed when something, such as wood or coal, is burned

data – n. facts or information used usually to calculate, analyze⁹, or plan something

zip code – n. a group of numbers that is used in the U.S. as part of an address to identify a mail delivery area

cubic – adj. a measurement that is produced by multiplying something's length by its width and height

1 soot   

n.煤烟，烟尘；vt.熏以煤烟

参考例句：

• Soot is the product of the imperfect combustion of fuel.煤烟是燃料不完全燃烧的产物。
• The chimney was choked with soot.烟囱被煤灰堵塞了。

2 diabetes   

n.糖尿病

参考例句：

• In case of diabetes, physicians advise against the use of sugar.对于糖尿病患者，医生告诫他们不要吃糖。
• Diabetes is caused by a fault in the insulin production of the body.糖尿病是由体內胰岛素分泌失调引起的。

3 blockages   

n.堵塞物( blockage的名词复数 )；堵塞，阻塞

参考例句：

• The storms could increase the risks posed by river blockages. 暴风雨会增加因河道堵塞所造成的危险。 来自互联网
• An angiogram shows the location and severity of blockages in blood vessels. 冠状动脉造影能够显示血管内的阻塞位置以及阻塞的严重程度。 来自互联网

4 particulate   

adj.微小的；n.微粒，粒子

参考例句：

• A special group was organized to dig up the particulate of the case.成立了一个专门小组来查明该案件的各个细节。
• Lungs retain relatively insoluble particulate material.肺脏内留有不溶解的颗粒物质。

5 disorders   

n.混乱( disorder的名词复数 )；凌乱；骚乱；（身心、机能）失调

参考例句：

• Reports of anorexia and other eating disorders are on the increase. 据报告，厌食症和其他饮食方面的功能紊乱发生率正在不断增长。 来自《简明英汉词典》
• The announcement led to violent civil disorders. 这项宣布引起剧烈的骚乱。 来自《简明英汉词典》

6 intestinal   

adj.肠的；肠壁；肠道细菌

参考例句：

• A few other conditions are in high intestinal obstruction. 其它少数情况是高位肠梗阻。 来自辞典例句
• This complication has occasionally occurred following the use of intestinal antiseptics. 这种并发症偶而发生在使用肠道抗菌剂上。 来自辞典例句

7 afterward   

adv.后来；以后

参考例句：

• Let's go to the theatre first and eat afterward. 让我们先去看戏，然后吃饭。
• Afterward,the boy became a very famous artist.后来，这男孩成为一个很有名的艺术家。

8 asthma   

n.气喘病，哮喘病

参考例句：

• I think he's having an asthma attack.我想他现在是哮喘病发作了。
• Its presence in allergic asthma is well known.它在过敏性气喘中的存在是大家很熟悉的。

9 analyze   

vt.分析，解析 (=analyse)

参考例句：

• We should analyze the cause and effect of this event.我们应该分析这场事变的因果。
• The teacher tried to analyze the cause of our failure.老师设法分析我们失败的原因。