一項研究發現，與歐洲和北美的PM2.5相比，中國的PM2.5致命性要低得多。中國疾病預防控制中心專家周脈耕領導的這個研究團隊提出，這是因為中國的空氣污染源于從干旱地區吹來的大量天然塵土，而西方的污染主要來自工業。

Smog in Europe and North America could be more than 25 times more lethal than the average air pollution found in Chinese cities, a new study suggests.
一項最新研究發現，歐洲和北美的霧霾致命性可能比中國城市平均空氣污染水平高出25倍以上。

In the largest ever study of its kind in the developing world, researchers tested the effects of air pollution on the health of people in 272 cities in China.
在這項有史以來針對發展中國家進行的最大規模的同類研究中，研究人員測試了中國272個城市里空氣污染對人體健康的影響。

They found average annual exposure to fine particles, known as PM2.5, in those cities was more than five times higher than the level recommended by the World Health Organisation (WHO), according to a paper in the American Journal of Respiratory and Critical Care Medicine.
研究人員發現，在這些城市中，人們的年均PM2.5接觸量是世界衛生組織建議水平的5倍多。研究論文發表在《美國呼吸系統和重癥護理醫學雜志》上。

However they also discovered that it was much less likely to increase the death rate than PM2.5 in Europe and North America.
但研究人員也發現，與歐洲和北美的PM2.5相比，中國的pm2.5致命性要低得多。

The researchers, led by Dr Maigeng Zhou, of the Chinese Centre for Disease Control and Prevention, suggested this was because China is affected by large amounts of natural dust blown by the wind from arid areas, while most pollution in the West comes from industry.
中國疾病預防控制中心周脈耕博士領導的這個研究團隊提出，這是因為中國的空氣污染源于從干旱地區吹來的大量天然塵土，而西方的污染主要來自工業。

They found that for every increase of 10 micrograms of air pollution in a cubic metre of air, the mortality rate increased by 0.22 percent, discounting deaths from accidents.
他們發現，如果不考慮意外事故造成的死亡，中國每立方米空氣里的污染物每增加10微克，死亡率就增加0.22%。

Professor Frank Kelly, an expert in environmental health at King’s College London, who was not involved in the study but has studied air pollution in China, told The Independent: “Those relative risks are considerably less than those seen in Europe and the US.
英國倫敦大學國王學院環境健康專家弗蘭克-凱利教授告訴《獨立報》記者：“這些相對的風險明顯比歐洲和美國小得多。”凱利沒有參與此項研究，但研究了中國的空氣污染。

“For premature mortality [in Europe] we are working on a six percent increase per 10 micrograms.”
凱利說：“就（歐洲的）過早死亡率來看，每立方米空氣污染物每增加10微克，死亡率將增加6%。”

That suggests air pollution in Europe is about 27 times more toxic than average air pollution in China.
這表明，歐洲空氣污染的毒性約為中國的27倍。

However Professor Kelly said cities like Beijing, Shanghai and Hong Kong were likely to suffer from Western-style air pollution.
但是，凱利教授說，北京、上海和香港這樣的城市可能也存在“西式”空氣污染。

"The natural dust component there is not of the magnitude that it would dwarf the coal, biomass and fossil fuel signals,” he said.
“那兒空氣中天然塵土的數量還不足以使煤炭、生物物質和化石燃料等因素相形見絀。”

“That [the lower mortality rate] may be true in certain cities whose pollution is not dominated by local power generation or major traffic congestion.”
他說：“在污染物主要不是來自當地電廠或嚴重交通擁堵的某些城市，（死亡率較低）可能是事實。”

Natural dust particles can cause physical damage to the lungs and trigger an asthma attack. Particles of carbon produced when fossil fuels are burned can lead to similar problems but they are also coated with toxic heavy metals, chemicals and volatile organic compounds.
天然粉塵可能使肺部受損，引發哮喘。燃燒化石燃料時產生的碳微粒可能導致類似問題，但它們外表還包裹著有毒的重金屬、化學物質和揮發性有機物。

These are able to pass from the lungs into the blood stream where it is thought they cause further damage to the body.
這些物質可能從肺部進入血液，據稱這會給身體造成進一步損害。

Areeba Hamid, an air pollution campaigner with environmental group Greenpeace, said: “Toxic air causes havoc to people’s health wherever in the world they live.
環境團體綠色和平組織的反空氣污染活動家阿麗芭-哈米德說：“有毒空氣給世界各地人們的健康造成嚴重損害。”

“We now know fumes from diesel vehicles are a lot more toxic than car companies claimed and this is a big cause of air pollution in Europe and North America.
“我們如今知道，柴油車排放的廢氣毒性比汽車公司宣稱的要大得多，而這是歐洲和北美空氣污染的一大原因。”

“These companies have a lot to answer for, but so far they’ve managed to avoid any real accountability.”
“這些公司要承擔很大責任，但到目前為止它們都避免承擔任何真正的責任。”

The study of cities in China found the average annual expose to PM2.5 was 56 micrograms per cubic metre, compared to the WHO guideline limit for safe air quality of 10 micrograms.
對中國城市的這項研究發現，PM2.5的年均接觸量為每立方米56微克，而世界衛生組織的空氣質量安全標準為每立方米10微克。

People who were older than 75, had less education or who lived in hotter places were more likely to die.
75歲以上、教育水平較低或生活在較熱地區的人死亡風險更高。

It is thought people in warmer cities were more likely to spend time outside or leave their windows open, thereby breathing more polluted air, the researchers said.
研究人員說，在較熱城市生活的人到戶外去或開窗的時間可能更長，因此會吸入更多的污染空氣。

They also speculated that less well educated people might have poorer access to health care or experience poorer environmental health conditions.
他們還推測說，教育水平較低的人享受醫療服務的機會較少，他們接觸的環境衛生狀況也較差。

英文來源：獨立報
翻譯&編審：yaning