Hong Kong
CNN
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Of the 100 cities with the world's worst air pollution last year, all but one were in Asia, according to a new report, showing that the climate crisis is playing a pivotal role in worsening air pollution and that the world's endangering the health of billions of people.
The majority of these cities (83) were in India, and all exceeded the World Health Organization's air quality guidelines by more than 10 times, according to a report by IQAir, which tracks air quality around the world.
This study focused specifically on fine particulate matter (PM2.5), the smallest and most dangerous pollutant. Of the more than 7,800 cities analyzed globally, only 9% recorded air quality that met the WHO standard that annual average levels of PM2.5 should not exceed 5 micrograms per cubic meter. .
Frank Hames, CEO of IQAir Global, said: “We see air pollution impacting every part of our lives.” “And in some of the most polluted countries, this effect can typically shave three to six years off people's lifespans. There will be years of preventable suffering.”
When inhaled, PM2.5 can travel deep into the lung tissue and enter the bloodstream. The disease originates from sources such as fossil fuel burning, dust storms and wildfires, and has been linked to asthma, heart and lung disease, cancer and other respiratory diseases, as well as cognitive impairment in children. Masu.
Begusarai, a city of 500,000 people in northern India's Bihar state, became the world's most polluted city last year with an annual average PM2.5 concentration of 118.9 (23 times the WHO guidelines). It was followed by the city of Guwahati in India's Assam state in the IQAir ranking. Delhi; and Mullanpur, Punjab.
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According to the report, 1.3 billion people across India, or 96% of the population, live in air quality that is more than seven times the WHO guidelines.
Central and South Asia was the world's worst performing region, with all four of the most polluted countries last year – Bangladesh, Pakistan, India and Tajikistan.
South Asia is of particular concern, with 29 of the 30 most polluted cities located in India, Pakistan and Bangladesh. The report ranks major population centers Lahore at 5th place, New Delhi at 6th place and Dhaka at 24th place.
Hames said there would be no significant improvement in pollution levels in the region without “major changes in energy infrastructure and agricultural practices.”
“Also, the concern in many parts of the world is that what is contributing to outdoor air pollution is in some cases also contributing to indoor air pollution,” he added. Ta. “Therefore, cooking with dirty fuels can result in indoor exposures that are many times greater than outdoor exposures.”
03:08 – Source: CNN
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IQAir found that of the 7,812 locations in 134 countries, territories and territories it analyzed for average air quality last year, 92.5% exceeded WHO PM2.5 guidelines.
Only 10 countries and territories had “healthy” air quality: Finland, Estonia, Puerto Rico, Australia, New Zealand, Bermuda, Grenada, Iceland, Mauritius, and French Polynesia.
Every year, millions of people die from health problems related to air pollution. Air pollution from fossil fuels kills 5.1 million people each year worldwide, according to a study published in the BMJ in November. Meanwhile, the WHO says that 6.7 million people die each year from the combined effects of ambient and household air pollution.
The IQAir report said the human-caused climate crisis caused by the burning of fossil fuels plays a “crucial” role in influencing air pollution levels.
The climate crisis is changing weather patterns, leading to changes in wind and rainfall, and affecting the spread of pollutants. Climate change will only worsen pollution as extreme heat becomes more severe and frequent, the report said.
The climate crisis is also causing more severe wildfires and longer and more intense pollen seasons in many regions, both of which are exacerbating health problems related to air pollution.
“The causes of the climate crisis and the causes of air pollution are highly interwoven,” Hames said. “Everything we can do to reduce air pollution will also have a huge impact on improving climate gas emissions in the long term, and vice versa.”
The wildfires that raged in Canada from May to October last year caused significant damage to North America. The monthly average air pollution in Alberta in May was nine times higher than the same month in 2022, the report said.
And for the first time, Canada has surpassed the United States in the regional pollution rankings.
Wildfires also affected U.S. cities such as Minneapolis and Detroit, with annual pollution averages increasing by 30% to 50% compared to the previous year. For the second year in a row, Columbus, Ohio, was the most polluted major U.S. city in 2023. However, major cities such as Portland, Seattle and Los Angeles saw their annual average pollution levels drop significantly, the report said.
However, in Asia, pollution levels have recovered in much of the region.
According to the report, China has reversed a five-year trend of declining pollution levels. Chinese cities once topped the rankings of the world's worst air quality, but a number of clean air policies over the past decade have improved the situation.
A study last year found that the campaign increased the average life expectancy of Chinese citizens by 2.2 years. However, thick smog returned to Beijing last year, with citizens experiencing a 14% increase in average annual PM2.5 concentrations, according to the IQAir report. Hotan, China's most polluted city, was ranked 14th in the IQAir ranking.
The Philippines was the only region in Southeast Asia to see lower annual pollution levels compared to the previous year, the report said.
According to the report, Indonesia is the most polluted country in the region, with a 20% increase compared to 2022. Indonesia, Vietnam, and Thailand all had cities that exceeded WHO's PM2.5 guidelines by more than 10 times.
Last month, Thai authorities ordered government workers to work from home, citing unhealthy levels of pollution in the capital Bangkok and surrounding areas, Reuters reported. Toxic smog brought on by seasonal agricultural burning blanketed the northern city on Friday, making tourist hotspot Chiang Mai the world's most polluted city.
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Inequality…and one bright spot
The report also highlights worrying inequalities: countries in Africa, South America and the Middle East lack monitoring stations, resulting in a lack of air quality data in these regions. There is.
In Africa, the number of countries included in this year's report has improved compared to previous years, but the continent remains the most underrepresented. According to IQAir, only 24 out of 54 African countries had sufficient data from their monitoring stations.
The 2023 ranking includes seven new African countries, including Burkina Faso, the world's fifth most polluted country, and Rwanda, ranked 15th.
Several countries that ranked high on the most polluted list last year were not included in 2023 due to lack of available data. This includes Chad, which became the most polluted country in 2022.
“There's still a lot of hidden air pollution on Earth,” Hames says.
One bright spot is the increasing pressure and public engagement from communities, NGOs, businesses, and scientists to monitor air quality.
“This is great because ultimately it shows the government that people care,” Hames said.
