Pollution is one of the biggest issues of modern society, often brought on by urbanization and industrialization. But which are the most polluted cities of them all? Every year, Mercer compiles its Health and Sanitation list, which ranks cities across the globe according to their level of cleanliness. The lower the score, the dirtier the city. Following, based on the latest statistics issued by Mercer, we would like to present you with a list we have compiled of the top 7 dirtiest cities in the world. Curious to learn which cities are having troubles managing their pollution levels? Let’s take a look at the countdown.