Air pollution continues to be one of the biggest global threats to human health in 2025. Multiple countries have put stricter policies and advanced technology to control it, yet they are still struggling with dangerously high pollution levels. According to the latest data from the World Population Review, here are the 9 most polluted countries in 2025 based on its Air Quality Index score.
| Rank | Country | Air Quality Index | PM2.5 Legend |
| 1 | Chad | 176 | 91.8 |
| 2 | Bangladesh | 167 | 78 |
| 3 | Pakistan | 164 | 73.7 |
| 4 | Democratic Republic of Congo | 153 | 58.2 |
| 5 | India | 138 | 50.6 |
| 6 | Tajikistan | 128 | 46.3 |
| 7 | Nepal | 119 | 42.8 |
| 8 | Uganda | 115 | 41 |
| 9 | rwanda | 114 | 40.8 |
Chad
Chad topped the list of the World’s most populated country with an Air Quality Index of 176. The main cause of the increasing pollution in Chad is frequent dust storms and large-scale biomass burning, which raise its PM2.5 levels, reaching a concerning 91.8.
Bangladesh
Bangladesh holds the second position in the list with an Air Quality Index of 167. The main contributors to pollution are emissions from brick kilns, heavy vehicle congestion, and the burning of both industrial and household waste, which raise high PM2.5 levels, reaching a concerning 78.
Pakistan
Pakistan comes third in the list with an Air Quality Index of 164. The main cause of its rising PM2.5 level of 73.7 is vehicle emissions, industrial pollution, and the seasonal practice of crop residue burning.
Democratic Republic of Congo
Democratic Republic of Congo comes second last in the top 5 with an Air Quality Index of 153. The PM2.5 level reached 58.2 due to industrial activities, agricultural practices, and widespread burning.
India
India comes in the top 5 position with an Air Quality Index of 138. The main contributors to pollution are vehicle emissions, industrial pollution, and the seasonal practice of crop residue burning, which raise high PM2.5 levels, reaching a concerning 50.6.
Manisha Chauhan is a passionate journalist with 3 years of experience in the media industry, covering everything from trending entertainment buzz and celebrity spotlights to thought-provoking book reviews and practical health tips. Known for blending fresh perspectives with reader-friendly writing, she creates content that informs, entertains, and inspires. When she’s not chasing the next viral story, you’ll find her diving into a good book or exploring new wellness trends.
