華北霧霾平均令人減壽5.5年,誰來買單

China’s air pollution has cut life expectancy by 5.5 years in the north of the country and caused higher rates of lung cancer, heart attacks and strokes, according to a groundbreaking study.

一項突破性研究顯示，中國的空氣污染已使中國北方居民的預期壽命減少5.5年，還提升了肺癌、心臟病和中風的發病率。

The worsening toxic smog in northern China became an issue of national concern after air pollution spiked to record levels in Beijing in January. Worried citizens have made runs on air filters and face masks, and “pollution domes” that provide filtered air for sports activities are increasingly common.

今年1月北京的空氣污染程度飆升至創紀錄水平後，中國北方不斷惡化的有毒霧霾成爲一個舉國關切的問題。憂心忡忡的居民搶購空氣過濾器和口罩，爲體育活動提供過濾空氣的“空氣淨化穹頂”也日益常見。

But the body of scientific research on the health impact is slim because there is little historical precedent for prolonged exposure to such high levels of air pollution.

但是，有關健康影響的科研文獻迄今較少，因爲歷史上很少有這樣持續暴露於高度空氣污染的先例。

Using decades of pollution data from across China, the new study, co-authored by professors from Massachusetts Institute of Technology in the US, Tsinghua University and Peking University in Beijing, and the Hebrew University of Jerusalem, calculates that air pollution in the north caused the loss of 2.5bn years of human life expectancy during the 1990s.

新的研究利用中國各地數十年期間的污染數據，並由美國麻省理工學院(MIT)、北京的清華大學和北京大學，以及耶路撒冷希伯來大學(Hebrew University of Jerusalem)的多名教授聯名發表報告。據這項研究估算，華北的空氣污染已在上世紀90年代總共減少25億年的人類預期壽命。

The findings show the health impact of air pollution is far higher than previously believed.

研究結果顯示，空氣污染的健康影響遠高於此前的認識。

“This is the first time anyone has got the data to show how severe long-term pollution affects human health, both in terms of life expectancy and the types of disease,” said Li Hongbin, an economics professor at Tsinghua University and a co-author of the study.

“這是第一次有人拿出數據顯示，長期污染多麼嚴重地影響人體健康，無論是就預期壽命還是就疾病類型而言，”清華大學經濟學教授、此項研究的聯名作者之一李宏彬表示。

“It shows how high the cost of pollution is in terms of human life – and that it is worth it for the government to spend more money to solve the pollution issue, even if we have to sacrifice growth.”

“它顯示出，就人類壽命而言，污染的代價有多高，這進而說明，政府加大投入、解決污染問題是值得的，即便我們必須犧牲一些增長。”

Mr Li estimates the shorter life expectancy identified by the study in northern China is equivalent to reducing the work force there by one-eighth.

李宏彬表示，這項研究發現的華北居民預期壽命縮短，相當於把當地勞動力人數削減八分之一。

China’s breakneck economic development during the past three decades has been accompanied by the widespread degradation of air, soil and water. Environmental worries are now a growing source of social unrest and public protest, particularly because of health concerns.

過去30年期間，中國經濟突飛猛進的同時，也出現了空氣、土壤和水源的大範圍退化。環境擔憂，尤其是健康關切，如今日趨成爲社會不安定和公開抗議的來源。

In response, Beijing has tightened environmental laws and regulations but these efforts have so far had little impact in reversing decades of damage.

作爲迴應，北京方面收緊了環保法律法規，但這些努力在逆轉數十年的損害方面迄今收效甚微。

The study, published on Monday in the US journal, Proceedings of the National Academy of Sciences, compares populations north and south of the Huai River, which runs through central China. North of the river, the government distributed free coal for heating in winter, resulting in higher rates of air pollution compared with areas to the south.

研究報告週一發表於《美國國家科學院院刊》(Proceedings of the National Academy of Sciences, PNAS)。這項研究比較了橫貫中國中部的淮河南北的居民。在淮河以北，政府免費發放煤炭用於冬季取暖，造成這些地區與南方相比空氣污染程度較高。

“What we found is that people who live just north of the river have life expectancy of five and a half years [less],” said Michael Greenstone, a professor of environmental economics at MIT and a co-author of the study.

“我們發現，生活在這條河北岸的人，預期壽命就少了5年半，”麻省理工學院環境經濟學教授、此項研究的聯名作者之一邁克爾•格林斯通(Michael Greenstone)表示。

“Part of the novelty of this study is that this was conducted with data on actual pollution measurements in China, and actual health and life expectancy in China. It is not an extrapolation,” he said.

“這項研究的部分新穎之處在於，它是根據中國實際污染測量數據，以及中國的實際健康和預期壽命數據進行的。沒有使用外推法，”他表示。

Using pollution data from 1981-2000 and health data from 1991-2000, the study found that an increase of 100 micrograms of total particulate matter per cubic metre (a measure of air pollution), corresponded to a three-year reduction in average life expectancy.

使用1981年至2000年的污染數據和1991年至2000年的健康數據，這項研究發現，每立方米空氣所含的總顆粒物（空氣污染的一種衡量標準）增加100微克，就對應於平均預期壽命減少3年。

Most previous calculations of the health cost of Chinese pollution are extrapolated from research conducted in the US, where overall pollution levels are much lower.

此前，有關中國污染造成的健康代價的多數估算，都是根據美國進行的研究推算出來的，但美國的總體污染水平低得多。