Eighty-three cities in India made it onto IQAir’s yearly list of the 100 most polluted cities, with nearly all (99) of the cities featured located in Asia.
The sixth annual World Air Quality Report reveals that in India, a staggering 1.3 billion people, which accounts for 96% of the population, are exposed to air quality levels seven times higher than the guidelines set by the World Health Organization (WHO).
The research focused on fine Particulate Matter, known as PM2.5, which is both the smallest pollutant and the most hazardous. Out of over 7,800 cities examined worldwide, only 9% achieved air quality levels compliant with the WHO’s directive, which stipulates standards for annual PM2.5 levels should not surpass 5 micrograms per cubic meter.
PM2.5, a fine particulate matter, can deeply infiltrate lung tissue and enter the bloodstream when inhaled. Originating from sources like fossil fuel combustion, dust storms, and wildfires, it is associated with asthma, cardiovascular and respiratory diseases, cancer, and cognitive impairment in children.
Frank Hammes, the CEO of the Swiss-based IQAir Global, highlighted the severity of air pollution in major cities, suggesting that in some areas, poor air quality could potentially be shaving off anywhere between three to six years of people’s lives.
Begusarai, a city in Bihar, northern India, home to half a million people, topped the list as the world’s most polluted city last year.
It recorded an average annual PM2.5 concentration of 118.9, which is 23 times higher than the WHO guidelines. Following Begusarai in the IQAir rankings were other Indian cities including Guwahati in Assam, Delhi, and Mullanpur in Punjab.
Central and South Asia emerged as the epicentre of global air pollution, hosting 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 in India, Pakistan, and Bangladesh.
The report ranked the major population centres of Lahore 5th, New Delhi 6th, and Dhaka in 24th place.
Hammes emphasized that significant reductions in pollution levels across the region are improbable without substantial alterations to both energy infrastructure and agricultural methods.
He also raised concerns about the dual nature of pollution sources, “worrisome in many parts of the world is that the things that are causing outdoor air pollution are also sometimes the things that are causing indoor air pollution,” he added.
“So, cooking with dirty fuel will create indoor exposures that could be many times what you’re seeing outdoors,” said Hammes.
Out of 7,812 locations across 134 territories to submit data, only 10 countries and territories, including Finland, Estonia, Puerto Rico, Australia, New Zealand, Bermuda, Grenada, Iceland, Mauritius, and French Polynesia, were found to have “healthy” air quality.
The health effects of air pollution claim millions of lives each year. A recent study in the BMJ found that air pollution from fossil fuels is responsible for approximately 5.1 million deaths globally annually.
Additionally, according to WHO, approximately 6.7 million people die each year from coupled ambient and household air pollution.
Air pollution by region
North America was badly affected by wildfires that raged in Canada from May to October last year. In May, air pollution in Alberta was nine times higher than in 2022, the report found.
In the regional pollution rankings, Canada surpassed the US for the first time. The wildfires affected cities in the US, including Minneapolis and Detroit, where annual pollution averages increased by 30% to 50% compared to the previous year. Columbus, Ohio retained its position as the most polluted major US city for the second consecutive year in 2023.
However, major cities such as Portland, Seattle, and Los Angeles saw notable decreases in annual average pollution levels, according to the report.
However, in Asia, pollution has increased in many parts of the region. In the report, it was found that China reversed a five-year trend of declining pollution levels. Chinese cities were previously prominent in global rankings for the worst air quality, but a series of clean air policies implemented over the past decade have led to significant improvements.
A study conducted last year revealed that the campaign had extended the average lifespan of Chinese citizens by 2.2 years. However, thick smog reappeared in Beijing last year, resulting in a 14 % rise in the annual average PM2.5 concentration for its residents, as reported by IQAir. Hotan, China’s most polluted city, ranked 14th in IQAir ranking.
The report revealed that in Southeast Asia, only the Philippines experienced a decrease in annual pollution levels compared to the previous year.
Indonesia emerged as the most polluted country in the region, with a 20% increase compared to 2022. Within Indonesia, Vietnam, and Thailand, several cities exceeded WHO PM2.5 guidelines by more than ten times, according to the report.
Last month, Thai authorities mandated government employees to work from home due to unhealthy pollution levels in Bangkok and surrounding areas, as reported by Reuters. Additionally, Chiang Mai, a popular tourist destination, became the world’s most polluted city last Friday due to toxic smog resulting from seasonal agricultural burning.
The report also highlighted a concerning disparity: the absence of monitoring stations in African, South American, and Middle Eastern countries, leading to a lack of air quality data in those regions.
While Africa saw an improvement in the number of countries included in this year’s report compared to previous years, the continent remains largely underrepresented. According to IQAir, only 24 out of 54 African countries had sufficient data available from their monitoring stations.
Seven African countries were among the new locations included in the 2023 rankings, including Burkina Faso, ranked 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 the 2023 report due to a lack of available data, including Chad, which held the title of the most polluted country in 2022.
Photo: Kartavya Path, a boulevard of New Delhi, is shrouded in hazardous smog, highlighting the city’s inclusion among the top 100 most polluted cities globally, with 82 other Indian cities sharing this unfortunate distinction.
(Credit: Mark Danielson/Flickr Commons)
Elham Asaad Buaras