How strange it is to know that not even a single country in the world has met the air quality standards set by WHO in 2021. The conclusion came as a result of an assessment of pollution data from 6,475 cities. Smog has also reappeared in some areas following a COVID-19-related dip.
After modifying its standards last year, the WHO now recommends that average yearly readings of microscopic and harmful airborne particles known as PM2.5 be no more than 5 micrograms per cubic meter, claiming that even low concentrations pose significant health hazards. According to data compiled by IQAir, a Swiss pollution technology company that monitors air quality, only 3.4 percent of the studied towns reached the threshold in 2021. PM2.5 levels were 10 times the permissible threshold in 93 cities.
New Delhi, the world’s most polluted capital
“There are a lot of countries that are making big strides in reduction,” said Christi Schroeder. Christi is an air quality science manager with IQAir. “China started with some very big numbers and they are continuing to decrease over time. But there are also places in the world where it is getting significantly worse.”
According to the report, India’s overall pollution levels deteriorated in 2021. New Delhi remained the world’s most polluted capital. However, Bangladesh placed #1, unchanged from the previous year to become the most polluted country. Chad came in second when statistics from the African country were added for the first time.
China, which has been waging war on pollution since 2014 fell to 22nd in the PM2.5 rankings in 2021, down from 14th place a year earlier; with average readings improving slightly over the year to 32.6 micrograms, IQAir said. Hotan, in Xinjiang’s northwestern area, had the worst air quality in China. It had an average PM2.5 reading of more than 100 micrograms, mostly due to sandstorms. Nonetheless, it was overtaken by Bhiwadi and Ghaziabad for third place on the list of the world’s most polluted cities.