Which city is the most polluted in the world?

IQAir is a Swiss air quality technology company that measures air quality based on concentrations of lung-damaging PM 2.5 particles. Its annual surveys are highly reputable and widely cited by researchers and government agencies.

Vehicles move through thick smog in Lahore, Pakistan. Photo: Reuters

A report on Tuesday (March 14) from IQAir showed that Lahore, Pakistan, is the most polluted city in the world in 2022. In addition, the report also pointed out that Chad (in central Africa) is the country with the worst air quality in the world.

In 2021, Lahore's PM 2.5 levels were 86.5 micrograms per cubic meter. This rose to 97.4 micrograms per cubic meter in 2022, making Lahore the world's most polluted city.

The second most polluted city after Lahore is Hotan - the only Chinese city in the top 20 of the ranking, with a PM 2.5 concentration of 94.3 micrograms/m3. Compared to the 2021 index of 101.5 micrograms/m3, Hotan shows signs of improving air quality.

The next two cities in the ranking are Bhiwadi (92.7) and Delhi (92.6), both in India.

Despite having 39 cities in the top 50 most polluted cities in the world, India only ranked 8th in the list of countries with the worst air quality globally. The top spot on the list belongs to Chad, with a PM 2.5 index of 89.7.

Second place went to Iraq, with a PM 2.5 index of 80.1. The third-placed country was Pakistan with a PM 2.5 of 70.9 micrograms/m3, followed by Bahrain with 66.6.

Bangladesh - the country with the worst air quality in 2021 - improved its ranking in 2022 with PM 2.5 levels falling from 76.9 to 65.8, placing fifth in the 2022 rankings.

India and Pakistan are the two countries with the worst air quality in Central and South Asia, where nearly 60% of the population lives in areas with PM 2.5 concentrations at least seven times higher than the World Health Organization's recommended level (maximum 5 micrograms/m3).

The report also said that worldwide, 1 in 10 people live in areas where air pollution has a negative impact on health.

The indices from the above rankings were produced using data from more than 30,000 air quality monitors at more than 7,300 locations in 131 countries, territories and regions.

Hoai Phuong (according to Reuters)

Source: https://www.congluan.vn/thanh-pho-nao-o-nhiem-nhat-the-gioi-post239346.html