Two indexes are provided by the platform, the first is the Pollution Index which provides an estimation of overall pollution levels in cities worldwide. It considers factors such as air and water pollution, garbage disposal, cleanliness, noise and light pollution, green spaces, and comfort in relation to pollution.
The second is the Pollution Exp Scale, which uses an exponential function to show very high numbers for very polluted cities and very low numbers for unpolluted cities.
With that said, below are 10 of the most polluted cities in Africa mid-way into 2023.
| Rank | City | Country | Pollution index | Exp pollution index |
|---|---|---|---|---|
| 1. | Cairo | Egypt | 91.2 | 164.7 |
| 2. | Lagos | Nigeria | 88.9 | 158.8 |
| 3. | Marrakech | Morocco | 82.9 | 148.4 |
| 4. | Casablanca | Morocco | 82.5 | 147.5 |
| 5. | Nairobi | Kenya | 79.8 | 142.3 |
| 6. | Addis Ababa | Ethiopia | 78.6 | 138.5 |
| 7. | Alexandria | Egypt | 74.3 | 130.6 |
| 8. | Tunis | Tunisia | 71.9 | 125.7 |
| 9. | Johannesburg | South Africa | 61.3 | 106.6 |
| 10. | Pretoria | South Africa | 56.1 | 97.0 |
Source: Africa Business Insider
