World’s Most Polluted Countries based on Air Quality

With increasing population, industrialization and advancement in technologies, the pollution levels are increasing at an alarming rate. According to the World Health Organization (WHO), there are countries whose pollution levels can cause a sore throat by a mere half an hour of sightseeing. 

Let us look at the most polluted country and region ranking based on annual average PM2.5 concentration (μg/m³). The data is compiled from the IQAir site from the historical data of 2018-2021. The World Health Organization’s air quality guidelines recommend that the annual mean concentrations of PM2.5 should not exceed 10 µg/m3 and 20 µg/m3 for PM10.

Countries with most Pollution


1. Bangladesh

Bangladesh is a country located in the southern region of Asia. It has seen in recent years a massive amount of economic growth as well as a population boom, with some 162 million or more people calling Bangladesh their home. This makes it the 8th most populous country worldwide, with a close proximity to other countries such as Myanmar, India, Nepal and China, many of which suffer from their own pollution related issues, with the economic giants of India and China taking many of the top spots in regards to most polluted cities across the globe.

In 2021, Bangladesh as a country came in with a PM2.5 reading of 76.90 μg/m³, that as mentioned put it in 1st place. This reading would also place it into the middle to higher end of the ‘unhealthy’ ratings bracket, which requires a PM2.5 reading of any number between 55.5 to 150.4 μg/m³ to be classed as such. 

2. Chad

Chad officially known as the Republic of Chad, is a landlocked country at the crossroads of North and Central Africa. It is bordered by Libya to the north, Sudan to the east, the Central African Republic to the south, Cameroon to the south-west, Nigeria to the southwest (at Lake Chad), and Niger to the west. Chad has a population of 16 million.

Chad is the 2nd most polluted country with PM2.5 reading of 75.90 μg/m³. Contributors to poor air quality in Chad include the oil, textile, and meatpacking industries, vehicle emissions, and waste burning.

3. Pakistan

Pakistan is a country located in south Asia, bordering on other highly prominent countries such as India, China, Iran and Afghanistan, all of which have sizeable pollution problems of their own. The economic giants that are India and China have many of their cities taking the top spots for some of the most polluted in the world, and Pakistan does not find much exception from this. Pakistan is an ancient region that has seen many cultures and kingdoms come and go, but now finds itself as an Islamic republic, with a massive population of some 212.2million inhabitants, making it the 5th most populous country in the entire world.

In 2021, Pakistan came in with a PM2.5 reading of 66.80 μg/m³, not only putting it into the ‘unhealthy’ ratings category, but also into the 3rd place position out of most polluted countries in the world. Two of its major cities, Gujranwala and Faisalabad, both came in the top 5 most polluted cities spot, taking 3rd and 4thplace, with PM2.5 readings of 105.3 μg/m³ and 104.6 μg/m³ respectively, numbers that place them into the higher end of the unhealthy bracket, making the air quality not only detrimental but outright severe for all members of the population.

4. Tajikistan

Tajikistan officially the Republic of Tajikistan is a landlocked country in Central Asia. It has an area of 143,100 km2 (55,300 sq mi) and an estimated population of 9,537,645 people.

In accordance with the World Health Organization’s guidelines, the air quality in Tajikistan is considered unsafe – the most recent data indicates the country’s annual mean concentration of PM2.5 is 59.4 µg/m3.

Contributors to poor air quality in Tajikistan include vehicle emissions, aluminum processing plants, and power generation.

5. India

India, officially the Republic of India is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the south, the Arabian Sea on the southwest, and the Bay of Bengal on the southeast, it shares land borders with Pakistan to the west; China, Nepal, and Bhutan to the north; and Bangladesh and Myanmar to the east. In the Indian Ocean, India is in the vicinity of Sri Lanka and the Maldives; its Andaman and Nicobar Islands share a maritime border with  Thailand,  Myanmar  and  Indonesia.

In 2019, as part of a worldwide survey, it was discovered that 21 out of the 30 most polluted cities were in India. And this pushed India’s ranking as a country to 5th place, according to figures published by The US AQI number averaged out at 152 and the PM2.5 figure recorded was 58.08µg/m³. This concentration was 5 times higher than that recommended by the World Health Organization (WHO). This is an overall improvement on the 2018 figure of 72.54µg/m³.

Over 50 over cent of this pollution comes from industry, followed by 27 per cent from vehicles, 17 per cent from crop burning and 7 per cent by domestic cooking. Over 2 million Indians lose their life to causes attributed to air pollution.

6. Oman

Oman, officially the Sultanate of Oman is a country in Western Asia. It is situated on the southeastern coast of the Arabian Peninsula, and spans the mouth of the Persian Gulf. Oman shares land borders with Saudi Arabia, the United Arab Emirates, and Yemen; while sharing maritime borders  with  Iran and  Pakistan.

In accordance with the World Health Organization’s guidelines, the air quality in Oman is considered unsafe – the most recent data indicates the country’s annual mean concentration of PM2.5 is 53.9 µg/m3. Contributors to poor air quality in Oman include crude oil production and refining and vehicle emissions. Available data indicates that Muscat and Sohar City have consistently high levels of air pollution.

7. Kyrgyzstan

Kyrgyzstan, officially the Kyrgyz Republic, is a landlocked country in Central Asia. It is bordered by Kazakhstan, Uzbekistan, Tajikistan and China, and its capital city is Bishkek. The population in 2020 was estimated to be just over 6.5 million people. For many years it was part of the Russian Empire and only became an independent state in 1991 after Mikhail Gorbachev’s democratic reforms in the USSR.

In 2019 the US AQI figure was 95 and the PM2.5 figure was three times higher than the World Health Organization’s (WHO) guidelines. At the end of 2020, the capital city of Bishkek was the dirtiest city in the entire world with a US AQI figure of 352.

8. Bahrain

Bahrain, officially the Kingdom of Bahrain, is an island country in Western Asia. It is situated on the Persian Gulf, and comprises a small archipelago made up of 50 natural islands and an additional 33 artificial islands, centered on Bahrain Island which makes up around 83 percent of the country’s landmass.

In accordance with the World Health Organization’s guidelines, the air quality in Bahrain is considered unsafe. The most recent data indicates the country’s annual mean concentration of PM2.5 is 49.8.

Contributors to poor air quality in Bahrain include sand storms, industrial pollution, private car transportation, and fertilizer manufacturing. Seasonal variations exist, with the highest levels in June and July and the lowest levels in December and January. Available data indicates that Kamad Town, Hidd, Ma’ameer, Manama, Nabih Saleh, and Ras Hayan have consistently high levels of air pollution.

9. Iraq

Iraq, officially the Republic of Iraq is a country in Western Asia. It is bordered by Turkey to the north, Iran to the east, the Persian Gulf and Kuwait to the southeast, Saudi Arabia to the south, Jordan to the southwest and Syria to the west. The capital and largest city is Baghdad.

In accordance with the World Health Organization’s guidelines, the air quality in Iraq is considered unsafe. The most recent data indicates the country’s annual mean concentration of PM2.5 is 49.7 µg/m3.

Contributors to poor air quality in Iraq include vehicle emissions, power generators, small fires especially from oil and gas refineries, and war-induced pollution. Available data indicates that Baghdad has consistently high levels of air pollution.

10. Nepal

Nepal is a landlocked country located in south Asia. It has a wide array of different geographical terrain within it, with large amounts of beautiful and pristine mountain ranges and valleys. Whilst these areas lend themselves to creating a wonderful image of Nepal, its geographical features also assist in the elevation of its already high pollution readings. It finds itself situated directly in between India and China, two economic giants in their own right as well as being the world’s top contributors to air pollution.

In terms of its PM2.5 levels, Nepal came in over 2021 with a reading of 46 μg/m³. This number puts it into the ‘unhealthy for sensitive groups’ bracket, which as the name implies, the air has potential health issues for those that are sensitive to pollution, including young children, the elderly, those with respiratory conditions as well as pregnant mothers.

Let me know your views on this article by commenting in the below section. You can follow the blog or subscribe to get the updates on the latest articles.

Follow us on twitter @DecodingBiosph1

One thought on “World’s Most Polluted Countries based on Air Quality

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s