SHANGHAI, March 22 – Not a single country has managed to meet the World Health Organization (WHO) air quality standard in 2021, a survey of air pollution data in 6,475 cities showed on Tuesday, and smog has slowed in some regions even recovered from a COVID-related slump.
The WHO recommends that average annual readings of small and dangerous airborne particles, known as PM2.5, should be no more than 5 micrograms per cubic meter after changing its guidelines last year, and said even low ones concentrations caused significant health risks.
But only 3.4% of cities surveyed met the standard in 2021, according to data from IQAir, a Swiss pollution technology company that monitors air quality. As many as 93 cities saw PM2.5 levels reaching 10 times the recommended level.
“There are many countries that are making great strides in mitigation,” said Christi Schroeder, air quality science manager at IQAir. “China started with some very large numbers and they continue to decline over time. But there are also places in the world where things are getting significantly worse.”
A woman crosses railroad tracks as a freight train passes by on a smoggy day in New Delhi, India November 12, 2021. REUTERS/Anushree Fadnavis/File Photo
India’s overall pollution worsened in 2021 and New Delhi remained the world’s most polluted capital, the data showed. Bangladesh was the most polluted country, also unchanged from a year earlier, while Chad ranked second after the African country’s data was included for the first time.
China, which has been waging war on pollution since 2014, fell to 22nd in the PM2.5 ranking in 2021 from 14th last year, with average readings improving slightly over the year to 32.6 micrograms said IQAir.
Hotan, in the northwest region of Xinjiang, was China’s worst-performing city, with average PM2.5 levels exceeding 100 micrograms, mostly caused by sandstorms.
It fell to third place on the list of the world’s most polluted cities after being overtaken by Bhiwadi and Ghaziabad, both in India.
reporting by David Stanway; Edited by Christian Schmollinger