别再吐槽国内的雾霾了，美国的空气也不怎么样

Nearly everyone on earth breathes unsafe air.

差不多所有地球人都在呼吸不安全的空气。

That’s according to a new comprehensive study from the Health Effects Institute and the Institute for Health Metrics and Evaluation, with expert input from the University of British Columbia. The Institute used satellite data and improved monitoring tools to conduct their research, and the results are bleak. Not only is the vast majority of the world’s population breathing unsafe air, but also the gap between wealthy countries and poor countries are increasing. There is now an 11-fold gap between the most- and least-polluted areas compared to a six-fold gap in 1990, according to Bob O’Keefe, the vice president of the Institute.

在不列颠哥伦比亚大学专家的协助下，健康影响研究所（Health Effects Institute）、健康指标评估研究所（Institute for Health Metrics and Evaluation）进行的最新综合性研究得出了这一结论。该研究所使用了卫星数据和改进的监测工具，研究结果很不乐观。不仅是全球绝大多数人口都在呼吸不安全空气，而且富裕国家和贫穷国家的差距也在不断扩大。据该研究所副总裁鲍勃.奥基夫介绍，目前空气污染最重地区和最轻地区的差异为11倍，而1990年时二者相差为6倍。

Exposure to pollution is associated with the increasing population of cities, but people who live in rural areas are also at risk. Burning solid fuels indoors makes the air inside a home dangerous to breathe. Globally, one in three people face unsafe air both indoors and outside. Air pollution is now the fourth leading cause of death worldwide, weighing in just below smoking, and the top environmental health risk. Pollution contributed to an estimated 6 million deaths in 2017.

人们受到污染影响与城市人口不断增长有关，但农村地区居民同样面临风险。在室内燃烧固体燃料会让家里的空气变得不适于呼吸 。全球范围内，有三分之一人口需要同时面对室内外不安全空气。空气污染目前排在吸烟之后，是全球第四大致死因素，也是最大的环境健康风险。据估计，2017年有600万人因此丧生。

Still, O’Keefe cited some cause for optimism. The number of people worldwide exposed to solid fuels indoors has fallen by over a billion since 1990, despite an increase in population, and China and India—two of the worst offenders when it comes to pollution—are improving their pollution controls.

不过，奥基夫也提到了一些乐观因素。1990年以来，尽管污染变得更加严重，生活在室内使用固体燃料环境中的世界人口减少了10亿以上。两个污染最严重的国家——中国和印度的治污情况正在改善。

But developing countries aren’t the only cause for concern. Between 2010 and 2016 there was an uptick in U.S. deaths where pollution was a contributing factor. Pollution-related deaths had previously been on a downward trend since 1990. In London, studies have shown that every area of the capital has pollution levels higher than global standards recommend. Cleaning up London’s air has become one of Mayor Sadiq Khan’s major initiatives.

但要担心的可不仅是发展中国家。2010-2016年，美国因污染而死亡的人数呈上升态势，而1990-2009年与污染有关的死亡人数一直在下滑。研究表明，伦敦的污染水平全面高于全球标准。让伦敦的空气变干净已经成为市长萨迪克.汗的重大举措之一。