空氣污染讓人郁悶還讓人笨？

This month, the Indian Medical Association declared a public health emergency in New Delhi because of high levels of air pollution. Schools were shut and emergency traffic restrictions put in place.

11月，印度醫(yī)學(xué)協(xié)會(Indian Medical Association)宣布由于空氣污染嚴(yán)重，新德里進(jìn)入公共健康緊急狀態(tài)。學(xué)校停課，緊急交通限制措施出爐。

Air pollution in New Delhi is nearly 30 times the level considered safe by the World Health Organization, causing more damage to the lungs than smoking two packs of cigarettes a day.

新德里的空氣污染程度超出世界衛(wèi)生組織(WHO)安全上限近30倍，其對肺的損害超過每日吸兩包香煙。

New Delhi is far from alone. Our research into the impact of air pollution in China shows that, in addition to the more obvious physical toll, air pollution can also have serious negative effects on mental health and cognition, significantly reducing a person’s happiness and their scores in verbal and mathematical tests.

新德里遠(yuǎn)非唯一一個。針對中國空氣污染影響的一項(xiàng)研究顯示，除了更明顯的身體傷害，空氣污染還可能給心理健康和認(rèn)知能力帶來嚴(yán)重負(fù)面影響，從而顯著降低人們的幸福感以及他們在語文和數(shù)學(xué)測試中的得分。

Such deleterious mental effects have serious negative consequences for livelihoods and human capital development, suggesting that development strategies should go beyond the traditional focus of boosting GDP in the developing word.

這類有害的心理影響對人們的生計(jì)和人力資本發(fā)展具有嚴(yán)重負(fù)面后果，似乎表明，發(fā)展戰(zhàn)略應(yīng)超越對提高發(fā)展中國家國內(nèi)生產(chǎn)總值(GDP)的傳統(tǒng)關(guān)注。

India’s recent pollution emergency is the most dramatic incidence of hazardous air pollution, but smoggy skies have been a cause of growing concern in most developing countries.

印度最近的污染緊急狀態(tài)是最具戲劇性的有害空氣污染事件，但霧蒙蒙的天空一直是讓多數(shù)發(fā)展中國家越來越擔(dān)憂的一件事。

Major cities across the developing world — from Thailand, to Brazil, to Nigeria — frequently experience pollution at several times the WHO safe limits. In fact, 98 per cent of cities with more than 100,000 residents in low and middle-income countries fail to meet the WHO’s air quality guidelines.

發(fā)展中國家(從泰國、巴西到尼日利亞)大城市的空氣污染程度經(jīng)常是WHO安全上限的好幾倍。實(shí)際上，在中低收入國家的居民超過10萬的城市中，有98%達(dá)不到WHO的空氣質(zhì)量標(biāo)準(zhǔn)。

China’s extreme levels of air pollution are well recognised, and examining the effects provides clear warnings for other countries seeking fast growth through rapid industrialisation.

中國的極端空氣污染水平是公認(rèn)的，考察其影響，將為尋求通過快速工業(yè)化實(shí)現(xiàn)快速增長的其他國家提供明確警告。

We used nationally representative longitudinal surveys on mental health and cognition, matched with daily air quality data for the time and place of interviews, to see what pollution does in a given time to individual happiness and cognitive performance. Because each person in our survey was observed multiple times, we can control for the effect of individual characteristics on the outcome variables.

我們利用具有全國代表性的精神健康和認(rèn)知縱向調(diào)查，結(jié)合訪談當(dāng)時當(dāng)?shù)氐拿咳湛諝赓|(zhì)量數(shù)據(jù)，考察了給定時間污染對個人幸福感和認(rèn)知表現(xiàn)的影響。由于我們在調(diào)查中對每個受訪者都進(jìn)行了多次觀察，我們能夠控制個體特征對調(diào)查結(jié)果變量的影響。

We found that worsening air quality in China led to a decrease in happiness that day equivalent to about 10 per cent of the reduced happiness one would experience from a negative major life event such as divorce.

我們發(fā)現(xiàn)，中國不斷惡化的空氣質(zhì)量造成的當(dāng)日幸福感下降程度，相當(dāng)于遭遇離婚等負(fù)面人生大事的10%左右。

The poor air quality across much of China that has accompanied rapid industrialisation and breakneck GDP growth could help to explain why several surveys have found stagnating or falling happiness in China since 2004.

在中國很多地區(qū)，糟糕的空氣質(zhì)量伴隨著快速工業(yè)化以及迅猛GDP增長，這可能有助于解釋為什么有多項(xiàng)調(diào)查發(fā)現(xiàn)，自2004年以來中國的幸福感出現(xiàn)停滯或下降。

Air pollution also significantly inhibits cognitive performance. We found that individuals exposed to polluted air when taking tests scored lower on both verbal and maths tests than when they were conducted under a clear sky.

空氣污染還顯著抑制了認(rèn)知表現(xiàn)。我們發(fā)現(xiàn)，在接受測試時處于空氣污染環(huán)境的個人在語文和數(shù)學(xué)測試中的得分，低于他們在晴朗天空下接受測試的結(jié)果。

The cumulative effect of pollution on test scores is even more pronounced than the immediate effect. An increase in the mean air pollution index for three years before testing had seven times the negative impact on scores than did a higher air pollution index on the testing day alone.

污染對于測試得分的累積影響甚至比即時影響還要明顯。如果在測試之前的3年期間平均空氣污染指數(shù)已然提高，其對得分的負(fù)面影響，是空氣污染水平僅僅在測試當(dāng)天較高的7倍。

The worse cumulative impact suggests that short-term measures to reduce pollution at times when enhanced mental capacity is needed, would do little to address the longer-term effects of exposure to harmful air.

累積影響更嚴(yán)重似乎表明，在需要較強(qiáng)智力時采取短期措施減少污染，基本上無助于解決暴露于有害空氣的較長期影響。

Similarly, though the effects on mental capacity were stronger for outdoor workers than for indoor workers, studies have shown that the smallest and most harmful air pollutants can, and do, enter buildings, so simply retreating indoors cannot spare us the ill effects.

同時，盡管空氣污染對戶外工作者智力的影響超過室內(nèi)工作者，但不止一項(xiàng)研究發(fā)現(xiàn)，顆粒最小、最有害的空氣污染物可以(而且確實(shí)會)進(jìn)入建筑物，因此只是躲在室內(nèi)并不能讓我們擺脫有害影響。

Even though many of our findings show the connection between pollution and mental health in the moment, the high number of high pollution days each year in many developing countries suggest that these transitory effects could become more permanent.

盡管我們的很多調(diào)查發(fā)現(xiàn)顯示，污染與心理健康之間的關(guān)系是暫時的，但很多發(fā)展中國家每年嚴(yán)重污染天數(shù)之多似乎表明，這類短暫影響可能會變得更具永久性。

The stronger cumulative than immediate effect of pollution on cognitive abilities indicates that short-term measures such as restricting traffic or discouraging citizens to go outdoors will not be enough to clear the haze from our minds and lift our spirits.

污染對認(rèn)知能力的累積影響比即時影響更強(qiáng)烈說明，限制交通或勸市民不要外出等短期措施，不足以驅(qū)散我們頭腦中的一團(tuán)霧水，并讓我們精神振作。

More broadly, policymakers must consider the trade-offs of economic growth at the expense of our environment for both our physical and our mental health.

更廣泛地說，政策制定者在掂量經(jīng)濟(jì)增長與環(huán)境退化之間的取舍時，必須考慮我們的身體和心理健康兩方面。

Rapid economic development in recent years has brought millions out of poverty, drastically reducing hunger, disease and mortality. But in much of the world this rapid growth has brought with it hazardous levels of pollution.

近年的快速經(jīng)濟(jì)發(fā)展讓數(shù)以百萬計(jì)的人脫離貧困，大大減少了饑餓、疾病和死亡率。但在世界的很多地區(qū)，這種快速增長也帶來了有害的空氣污染。

Previous research has linked cumulative exposure to pollution to Alzheimer’s disease and other forms of dementia, as well as poor stock market performance, increased crime and reduced life expectancy.

以往的研究還發(fā)現(xiàn)，長期暴露于污染與阿爾茨海默病和其他老年癡呆病癥;與股市表現(xiàn)低迷、犯罪率上升和預(yù)期壽命變短存在關(guān)聯(lián)。

Such negative side effects of industrial growth have measurable impacts on livelihoods and general welfare. As developing nations strive to improve the lives of their citizens, the downsides of growth strategies should be part of the calculation.

工業(yè)增長造成的這類負(fù)面副作用，對人們的生計(jì)和福祉有著可衡量的影響。隨著發(fā)展中國家努力改善人民生活，增長戰(zhàn)略的弊端應(yīng)該是考量的一部分。

Xiaobo Zhang is a senior research fellow at the International Food Policy Research Institute and professor of economics in the National School of Development at Peking University.

本文作者是國際食物政策研究所(IFPRI)高級研究員、北京大學(xué)國家發(fā)展研究院(National School of Development)經(jīng)濟(jì)學(xué)教授