Most Polluted Countries 2021

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Pollution is the introduction or presence of harmful substances or contaminants into the natural environment that causes adverse effects.

Pollution not only hurts the planet, but it is also harmful to humans. Air pollution caused by the burning of fossil fuels in factories, cars, airplanes, and electricity cause health problems such as breathing problems, worsening of asthma, and even congenital disabilities. According to Pure Earth, toxic pollution is among the leading risk factors for non-communicable diseases globally. Non-communicable diseases account for 72% of all deaths, 16% of which are caused by toxic pollution. Toxic pollution is responsible for 22% of all cardiovascular disease, 25% of stroke deaths, 40% of lung cancer deaths, and 53% of deaths from chronic obstructive pulmonary disease.

The Earth's soil and water can also become polluted from littering or the dumping of chemicals by industries and individuals. This pollution can damage ecosystems, negatively affect plants and trees, and contaminate our drinking water.

As the damage from pollution has become more apparent, more countries are looking to green alternatives to prevent further damage to the Earth. Solar and wind energy, eco-friendly building materials, and non-toxic products are increasingly being used to preserve the planet. While these green initiatives are taking place around the world, some countries have a long way to go.

According to the World Health Organization (WHO), ambient air pollution causes 4.2 million deaths every year. 91% of the world's population lives in places where air quality exceeds the WHO guidelines limits.

Particle Pollution

The World Health Organization evaluated the concentration of PM2.5 particles to determine the most polluted place on Earth. PM2.5 (fine particulate matter 2.5) refers to tiny particles or droplets in the air that are two and one-half microns or less in width. These particles come from car, truck, bus, and off-road vehicle exhausts and from operations that involve the burning of fossil fuels such as wood, heating oil, or coal. They can also originate from indoor sources such as smoking tobacco, cooking, burning candles, or using fireplaces.

PM2.5 is an air pollutant that is a concern for people's health when levels in the air are high. These particles reduce visibility and make the air appear hazy when levels are elevated. Some cities, such as New York, issue a PM2.5 Health Advisory when conditions are considered to be unhealthy for sensitive groups.

The Air Quality Index (AQI) is an index calculated for major air pollutants regulated by the Clean Air Act: particle pollution (PM2.5), ground-level ozone, carbon monoxide, and sulfur dioxide. The AQI ranges from 0 to 500, with zero representing clean air and 500 being the most hazardous. Values of 100 or below are generally thought of as satisfactory; however, when values are above 100, air quality is considered unhealthy for certain at-risk groups of people and becomes more unsafe as the value increases.

The cleanest countries in the world, as determined by the Environmental Performance Index (EPI), have high air quality, clean water, and strong environmentally-friendly policies and initiatives. These countries include Switzerland, France, and Denmark.

A total of 92 nations were evaluated to determine which had the highest number of PM2.5 – or which nations were the most polluted.

10 Most Polluted Countries in the World

1. Bangladesh

Bangladesh is the most polluted country in the world, with an average PM2.5 concentration of 83.30, down from 97.10 in 2018. The country's primary environmental pollutants are air and water pollution, groundwater contamination, noise pollution, and solid wastes. Dhaka City is one of the most polluted cities in the world. In terms of air pollution, Bangladesh's largest source is its brickmaking industry, which employs one million people and creates 23 billion bricks every year. The kilns used in brickmaking burn wood or coal and create mass amounts of smoke and dust. Due to increased demand for bricks, the brickmaking industry is only expected to grow more, leading to more air pollution.

2. Pakistan

The second-most polluted country in the world is Pakistan, which has an average PM2.5 concentration of 65.81. AQI levels in Punjab were consistently between the "near unhealthy" or "very unhealthy" ratings for most of 2019 and even reached as high as 484. Pakistan is experiencing rising pollution from the growing number of vehicles on the roads, large-scale losses of trees, smoke from bricks kiln and steel mills, and the burning of garbage. The Pakistan minister for climate change blamed India for Pakistan's smog; however, Pakistani citizens blame their government for simply not doing enough to monitor or combat the crisis.

3. Mongolia

Mongolia is the third-most polluted country in the world. Mongolia's average PM2.5 concentration is 62.00. The largest pollution source in Mongolia is the burning of coal and other biomass, such as wood or crop residue, in stoves. In Mongolia's capital, Ulan Bator, respiratory infections have increased 270% over the last ten years, and children that live in the capital city have a 40% lower lung function than those living in rural areas. About 70-90% of pregnant mothers being treated at a family health center in Mongolia are negatively impacted by air pollution. Infants as young as two days old are being diagnosed with pneumonia or other respiratory illnesses.

4. Afghanistan

Afghanistan is the fourth-most polluted country in the world, with an average PM2.5 level of 58.80. In 2017, numbers show that air pollution was more dangerous than the war in Afghanistan. That year, about 26,000 people lost their lives due to air pollution-related diseases while 3,483 people lost their lives due to conflict. About 80% of drinking water in Afghanistan is polluted as well due to low rainfall, irregular use of groundwater, and insufficient infrastructure in cities. The lack of clean drinking water commonly results in food poisoning.

5. India

India the fifth-most polluted country in the world, with an average PM2.5 concentration of 50.08. Of the 30 most polluted cities in the world, 21 of them are located in India. The most polluted city in India and the world is Kanpur, where the city's medical college receives about 600 respiratory illness patients per month. India's unhealthy pollution levels are from sources such as vehicles, the burning of coal and wood, dust storms, and forest fires. Delhi, India's capital region, is notorious for some of the worst air in India, forcing flight cancellations, causing traffic accidents, closing of schools, and even turned the white marble walls of the Taj Mahal green. Rural areas are just as, if not more, affected by pollution in India as they rely on things such as wood and dung for cooking and heating and still practice the burning of crop stubble.

6. Indonesia

Indoesia's average PM2.5 concentration is 51.71. About 250,000 people die in Indonesia every year because of pollution exposure, the fourth-highest premature pollution deaths in the world. Millions of children are exposed to poor air quality every year, causing them to miss school and leading to possible lifelong physical and cognitive damage. A few decades ago, Indonesia's air quality was considered among the cleanest in the world, while it is the sixth-most polluted globally today.

7. Bahrain

The fifth-most polluted country in the world is Bahrain, which has an average PM2.5 of 59.80. Bahrain has the worst air pollution in the Middle East. A Gulf country like Bahrain may not suffer from pollution caused by coal power plants or other human activity seen in cities, but rather from dust and sand storms that can pick up several harmful chemicals and even radioactive materials from as far as the Sahara.

8. Nepal

The seventh-most polluted country in the world is Nepal. Nepal's average PM2.5 concentration is 44.46. About 35,000 people in Nepal die every year from illnesses caused by air pollution. About 1 in 10 Nepalese now suffer from a chronic lung problem such as bronchitis or emphysema due to Nepal's worsening air conditions. A baby born today in Nepal is expected to have a two-year shorter life expectancy solely due to problems caused by the air. In the country's capital, Kathmandu, 80% of vehicles on the road are motorcycles, which are one of the leading urban polluters in addition to brick kilns.

9. Uzbekistan

Uzbekistan's average PM2.5 concentration is 41.20. According to the World Health Organization, Uzbekistan has the third-highest death rate associated with outdoor pollution in the world. Air quality in Uzbekistan, especially around Tashkent, is better during the spring and summer and worse during colder temperatures. Much of the country's pollution is from poor water management, heavy use of agricultural chemicals, salt and dust storms, factories, and auto emissions (only in Tashkent and Farghona).

10. Iraq

Iraq has the tenth-worst air pollution with an average PM2.5 concentration of 39.60. Iraq's poor air quality contributors are vehicle emissions, war-induced pollution, power generators, and small fires, mostly from oil and gas refineries. In 2016, researchers found that exposure to war-induced pollution, including explosions and the burning of military waste, is a cause of congenital disabilities and cancers.

Here are the 10 countries with the most pollution:

  1. Bangladesh (83.3)
  2. Pakistan (65.81)
  3. Mongolia (62)
  4. Afghanistan (58.8)
  5. India (58.08)
  6. Indonesia (51.71)
  7. Bahrain (46.8)
  8. Nepal (44.46)
  9. Uzbekistan (41.2)
  10. Iraq (39.6)

Most Polluted Countries 2021

* Data is from 2018.
Country Average PM2.5 (µg/m³) 2021 Population
Bangladesh83.3166,303,498
Pakistan65.81225,199,937
Mongolia623,329,289
Afghanistan58.839,835,428
India58.081,393,409,038
Indonesia51.71276,361,783
Bahrain46.81,748,296
Nepal44.4629,674,920
Uzbekistan41.233,935,763
Iraq39.641,179,350
China39.121,444,216,107
United Arab Emirates38.949,991,089
Kuwait38.34,328,550
Bosnia And Herzegovina34.583,263,466
Vietnam34.0698,168,833
Kyrgyzstan33.26,628,356
North Macedonia32.42,082,658
Syria32.218,275,702
Dr Congo32.192,377,993
Myanmar3154,806,012
Ghana30.331,732,129
Uganda29.147,123,531
Armenia25.512,968,127
Bulgaria25.496,896,663
Sri Lanka25.221,497,310
South Korea24.7851,305,186
Iran24.2785,028,759
Thailand24.2569,950,850
Kazakhstan23.618,994,962
Macau23.5658,394
Peru23.3833,359,418
Serbia23.38,697,550
Laos23.17,379,358
Chile22.6319,212,361
Greece22.510,370,744
Saudi Arabia22.535,340,683
South Africa21.5660,041,994
Nigeria21.4211,400,708
Algeria21.244,616,624
Cambodia21.116,946,438
Israel20.838,789,774
Turkey20.6285,042,738
Hong Kong20.37,552,810
Guatemala20.218,249,860
Georgia20.13,979,765
Ethiopia20.1117,876,227
Mexico20.02130,262,216
Cyprus19.721,215,584
Malaysia19.3632,776,194
Croatia19.094,081,651
Singapore195,896,686
Poland18.6737,797,005
Romania18.3219,127,774
Jordan18.310,269,021
Egypt18104,258,327
Philippines17.63111,046,913
Taiwan17.1623,855,010
Italy17.0960,367,477
Ukraine16.643,466,819
Slovakia16.15,460,721
Angola15.933,933,610
Brazil15.77213,993,437
Colombia14.6151,265,844
Argentina14.645,605,826
Hungary14.579,634,164
Lithuania14.492,689,862
Czech Republic14.4510,724,555
Latvia13.31,866,942
Belgium12.5211,632,326
France12.3465,426,179
Austria12.179,043,070
Japan11.36126,050,804
Germany11.0183,900,473
Netherlands10.9117,173,099
Switzerland10.898,715,494
Ireland10.64,982,907
United Kingdom10.5368,207,116
Costa Rica10.45,139,052
Puerto Rico10.212,828,255
Russia9.85145,912,025
Spain9.7446,745,216
Luxembourg9.6634,814
Denmark9.65,813,298
Malta9.4442,784
Portugal9.2610,167,925
United States9.04332,915,073
Ecuador8.617,888,475
Australia825,788,215
Canada7.7238,067,903
New Zealand7.524,860,643
Norway6.885,465,630
Sweden6.6310,160,169
Estonia6.151,325,185
Finland5.635,548,360
Iceland5.55343,353
Bahamas3.3396,913

Most Polluted Countries 2021