Which Is the Most Polluted City in the World? Latest Rankings & Data

Air pollution is not just a news headline any more. It is a daily reality to millions of people around the world as it influences the way they breathe, the way they feel and the way they are healthy in the long term. And, by the way, in case you have ever wondered which city in the world is the most polluted at the moment, or which cities in the world are the most polluted, you are right. Now, what the recent statistics tell us.

What Are We Actually Measuring?

Most global air quality rankings are based on something called PM2.5. These are tiny particles floating in the air that are so small they pass straight through your nose and throat and settle deep inside your lungs. The World Health Organisation (WHO) says safe annual levels should stay below 5 micrograms per cubic metre. As you'll see, most cities on this list exceed that by 10 to 25 times.

 

Prolonged contact with air that contains high amounts of PM2.5 may result in severe health issues such as asthma, bronchitis, heart disease and even lung cancer. The most vulnerable are children, the old, and individuals with pre-existing health conditions.

Which Is The Most Polluted City In The World?

The 2024 World Air Quality Report by IQAir states that the answer to the question of the most polluted city in the world is the small industrial town of Byrnihat, located on the border of Assam and Meghalaya, northeastern India. Not Delhi. Not Beijing. A town no-one, beyond India, has ever heard of. As of 2024, Byrnihat measured the mean annual PM2.5 of 128.2 µg/m 3. That is over 25 times the amount of what is safe to breathe as recommended by WHO. Why then is a small town topping a world list? The causes are not difficult to comprehend when you see what is going on the ground:

• Around 41 factories operate in and around the town, including iron and steel plants, cement factories, and ferroalloy units, many running with weak pollution controls.

• The town sits along a busy national highway connecting Assam and Meghalaya, so hundreds of heavy trucks pass through every day adding thick diesel fumes to the air.

• There is no full-time pollution control body stationed in the area. Officials travel from Shillong, nearly 70 km away, to carry out checks.

• Constant construction activity and hill-cutting stir up dust that hangs in the air for hours.

The impact on residents has been deeply worrying. Reported respiratory infection cases in the area jumped from 2,082 in 2022 to 3,681 in 2024. A local doctor noted that around 90% of patients at the town's health centre come in with coughs or breathing difficulties. People also report skin rashes and eye irritation. Even crops and clothes get coated in soot and dust.

Which Are The Most Polluted Cities In The World?

Byrnihat is the worst, but it is far from alone. The 2024 IQAir report found that South Asia dominates the global air pollution rankings, with India accounting for six of the world's nine most polluted cities. Here is a look at the other cities that consistently appear near the top.

Delhi, India

India's capital has long been associated with dangerous air quality, and 2024 was no better. Delhi's average annual PM2.5 levels actually increased compared to 2023, driven by vehicle emissions, crop burning in surrounding states, coal-fired power plants, and construction dust. With over 32 million people living there, the scale of harm is enormous. India's Supreme Court even stepped in during 2024, reaffirming that clean air is a fundamental right and ordering governments to act.

Lahore, Pakistan

One of the most polluted cities in the world and regularly leading real-time air quality rankings all year round, is Lahore. The level of pollution remains at very high levels due to a combination of lax control of industrial emissions and a large number of vehicles on the road. Local activists have long been demanding increased government action and improved monitoring, but it has been slow.

Dhaka, Bangladesh

In 2024, Bangladesh was the second most polluted country in the world, and its capital, Dhaka, contributed significantly to this. Blistering urbanisation, a thriving garment sector, and old-fashioned cars are just a few factors that contribute to some of the worst air quality indicators in the area.

N'Djamena, Chad

Chad was ranked the most polluting country in the world in 2024, and its capital, N'Djamena, was the second most polluting capital city after Delhi. One of the major problems in countries such as Chad is the lack of appropriate air quality monitoring, and thus, the actual pollution rates might be even lower than reported.

Other Indian Cities

Several other Indian cities also make the global top 20, including Faridabad, Gurugram, Noida, Bhiwadi, Loni, and Greater Noida. All of these record pollution levels far beyond the WHO's recommended limit, and many residents live with hazy skies and poor visibility for months at a time, particularly during winter.

What Is Being Done About It?

There are some signs of action, though change is slow. India's Supreme Court has ordered both central and state governments to strengthen pollution controls. Meghalaya's government has shut down seven factories in Byrnihat for breaking environmental rules. Southeast Asia as a whole showed some improvement in 2024, with PM2.5 levels declining across all countries in the region. That said, rapid industrialisation in many parts of the world is still outpacing efforts to clean up the air.

How Can You Protect Yourself?

Systemic change is what will ultimately fix this problem, but there are things you can do in the meantime to reduce your personal exposure:

• Check your city's air quality index every morning before stepping out.

• Wear an N95 mask on high-pollution days.

• Use a HEPA air purifier at home, especially in the bedroom.

• Keep windows closed when outdoor air quality is poor.

• Avoid outdoor exercise during winter mornings when smog is at its worst.

• See a doctor early if you notice any respiratory symptoms.

Conclusion

The data is clear. Air pollution is one of the most serious public health challenges of our time, and South Asia is bearing the heaviest burden. Byrnihat's rise to the very top of the global list is a stark reminder of what can happen when industrial growth outpaces environmental safeguards. But the problem isn't limited to one town or one country. Millions of people across the world are breathing unsafe air every single day.

 

What this means for ordinary families is that pollution-linked illnesses, hospital visits, and ongoing medical expenses have become a real part of life for many. This is where having reliable health insurance becomes truly important. Companies like Niva Bupa offer plans that help cover the cost of treatment for conditions like respiratory infections, heart disease, and other illnesses that are closely tied to long-term air pollution exposure.

 

Clean air is a right every person deserves. Until the air genuinely improves, staying informed and having the right protection in place is the most sensible thing you can do for yourself and your family.