1
The trade-in incentive is currently limited to Germany's 15 most polluted cities.
2
Among recent Olympics, Beijing looks to be the most polluted city.
3
The most polluted cities in the US and Canada are dominated by California.
4
The Chinese capital is one of the most polluted cities in the world.
5
Which are the world's two most polluted cities -and why?
6
Lone athletes can be seen running along polluted city streets and busy motorways.
7
However, the capital is the most heavily polluted city in Europe for NO 2 .
8
According to the WHO, 20 of the world's most polluted cities are in developing countries.
9
It's a business craze that's taking off throughout polluted cities, such as Beijing and Shanghai.
10
A look at life inside China's most polluted city.
11
Delhi, one of the world's most polluted cities, is home to more than 11 million people.
12
The most polluted city in the United States is the inland city of Visalia-Porterville in California.
13
In March, a spike in air contaminants briefly turned Paris into the world's most polluted city.
14
Earlier this month, Delhi became the most polluted city on Earth, as air quality reached terrifying levels.
15
The city of Baltimore is suing agrochemical giant Monsanto accusing them of polluting city waterways and stormwater.
16
The city surrounding it has often been ranked in the top 10 of the world's most polluted cities.