21.   Thousands of Parisians flee the polluted congested city for a fresh start in rural France.

22.   They woke to a sunny day and skies unusually clear for this notoriously polluted city.

23.   Beijing, Shanghai and Guangzhou are among the most polluted cities in the world.

24.   Bangkok is considered one of the most polluted cities in the world.

25.   The worst polluted city, according to the survey, is Mexico City, followed in ascending order by Baku, Dhaka, Mumbai, Almaty and New Delhi.

26.   Three-wheel taxis are blamed by the government for making Dhaka one of the most polluted cities in the world.

27.   It is also the fourth most polluted city in the world.

28.   Mexico -- whose capital is among the most polluted cities in the world -- has asked the bank for advice on how to implement a similar program.

29.   The money will be used to help clean up the environment in the highly polluted cities of Cairo and Alexandria.