A new study has found that people living in South and Central Asia experience some of the highest levels of air pollution in the world .
一项新研究发现，生活在南亚和中亚的人们承受着世界上最严重的空气污染之一。
The air in these areas has the highest amounts of the most kind of air pollution .
这些地区的空气中，危害最大的那类空气污染物含量最高。
A micron is one millionth of a meter .
一微米是一米的百万分之一。
PM2.5 is so small that it can enter human lungs and the blood .
PM2.5非常小，可以进入人的肺部和血液。
The Switzerland-based company IQAir released its latest study on Tuesday .
总部位于瑞士的IQAir公司周二发布了最新研究报告。
The company operates an air quality information system .
该公司运营着一个空气质量信息系统。
The yearly IQAir reports began in 2017 .
IQAir的年度报告始于2017年。
Glory Dolphin Hammes is chief of IQAir North America .
格洛丽·多尔芬·哈米斯是IQAir北美公司的负责人。
She told VOA : "PM2.5 actually kills more people than any other air quality pollutant .”
她对美国之音说：“实际上，PM2.5导致的死亡人数比其他任何空气污染物都多。”
Based on data from IQAir's worldwide network , Bangladesh is the country with the highest levels of PM2.5 air pollution .
根据IQAir全球网络的数据，孟加拉国是PM2.5空气污染水平最高的国家。
Chad , Pakistan , Tajikistan and India are also among the five nations with the lowest air quality .
乍得、巴基斯坦、塔吉克斯坦和印度也位列空气质量最差的五个国家之中。
IQAir found that New Delhi , India , is the capital city with the most PM2.5 pollution .
IQAir发现，印度新德里是PM2.5污染最严重的首都。
Dhaka , Bangladesh ; N'Djamena , Chad ; Dushanbe , Tajikistan ; and Muscat , Oman , are the other capital cities rated as having extremely polluted air .
孟加拉国达卡、乍得恩贾梅纳、塔吉克斯坦杜尚别和阿曼马斯喀特是其他被评为空气极度污染的首都。
People seeking the world's cleanest air will find it in the French overseas territory of New Caledonia .
想寻找世界上最清洁空气的人，可以在法国海外领地新喀里多尼亚找到。
The territory's main city , Noumea , is at the top of IQAir's clean air ranking .
该领地的主要城市努美阿位居IQAir清洁空气排名榜首。
Other places where the air is very clean include the U.S . Virgin Islands and Puerto Rico in the Caribbean .
空气非常清洁的其他地方包括加勒比海的美属维尔京群岛和波多黎各。
Cape Verde , in the Atlantic Ocean off the coast of Africa , also has very little air pollution .
位于非洲海岸外大西洋上的佛得角，空气污染也非常少。
Some parts of the developing world lack enough monitoring , Dolphin Hammes said .
多尔芬·哈米斯说，发展中国家的一些地区缺乏足够的监测。
Those areas include parts of Africa , the Middle East and South America .
这些地区包括非洲、中东和南美洲的部分地区。
Developed countries usually have a greater number of air quality monitors than developing countries and areas .
发达国家的空气质量监测器通常比发展中国家和地区多。
Monitoring is at a higher level than in past years in some countries , she said .
她说，一些国家的监测水平比往年更高。
In 2021 , air pollution levels increased from those of a year earlier : the first year of the COVID-19 pandemic .
2021年的空气污染水平比前一年（即新冠疫情的第一年）有所上升。
In 2020 , the world saw a decrease in air pollution because of less ground and air transportation .
2020年，由于地面和空中交通减少，全球空气污染有所下降。
Another reason for the rise in air pollution last year was an increase in wildfires , Dolphin Hammes said .
多尔芬·哈米斯说，去年空气污染加剧的另一个原因是野火增多。
The WHO said the reduction would prevent millions of deaths worldwide .
世卫组织表示，这一降低将在全球避免数百万人死亡。
Scientists supported the new recommendations .
科学家们支持这些新建议。
But they worry that some countries would have trouble reaching them .
但他们担心一些国家难以达到这些标准。
Much of the world was already failing to meet the 10-microgram limit , Reuters news agency reported .
据路透社报道，世界上许多地方本来就达不到10微克的上限。
IQAir's yearly reports are based on PM2.5 measurements from what is now a total of 6,475 cities in 117 countries , regions and territories .
IQAir的年度报告基于目前117个国家、地区和领地共6475个城市的PM2.5测量数据。
The worldwide information comes from "tens of thousands of regulatory and low-cost air quality monitoring stations ,” the company said .
该公司表示，这些全球信息来自“数以万计的官方及低成本空气质量监测站”。
The stations are operated by governments , nonprofit organizations , research centers and citizen scientists .
这些监测站由政府、非营利组织、研究中心和公民科学家运营。