Pollution is a big problem in many cities around the world. It has been a serious threat to environmentalist in all developed countries. Efforts are being made to overcome the growing pollution in the world but for some cities it's too much, and those are the ones where it hits the hardest. So if you're a neat freak avoid these 10 cities:

1. Baghdad - Iraq

2. Brunei - Darussalam

3. Dhaka - Bangladesh

Dhaka is the capital city of Bangladesh located in southern Asia, between Burma and India. The capital is battling with the constant threats of water pollution. Surface water is often thick with disease and pollutants from the use of commercial pesticides.

4. Karachi - Pakistan

Karachi is the most metropolitan and business hub of Pakistan. On one side the image of Karachi is being projected as major and industrial city of Pakistan but on other hand pollution-related diseases in Karachi are on the rise due to intolerable levels of air and noise pollution in the city. Some 35% of people in one way or another are affected by these ailments including cardiac, lung, ENT, skin, eye and psychological diseases.

5. Lagos - Nigeria

Lagos is the commercial capital and largest city in Nigeria. The hovering smoke over the city blurs the skyline of the central business area of Nigeria's commercial capital. The city of 12 million residents and one of the biggest cities in Africa is facing a huge air pollution problem.

6. Mexico City - Mexico

Mexico city the capital of Mexico has gone from among the worlds cleanest to among the dirtiest in the span of generation. The average visibility of some 100 km in 1940s is down to about 1.5 km. Snow-capped volcanoes that were once part of the landscape are now visible only rarely and levels of almost any pollutant like nitrogen dioxide is regularly breaking standards by two to three times. Levels of ozone a pollutant that protects us from solar radiation in the upper atmosphere but is dangerous to breathe, is twice as high here as the maximum allowed limit.

7. Moscow - Russia

Despite claims that Moscow is the most important and capital of Russia and where people pay an average $3,000 a month for a three bedroom apartment does not even have clean running water, Moscow also has a huge level of air pollution which is resulting in daily strain on lung health. Cholera is on the rise in some parts of Moscow due to filthy areas where there is no adequate arrangement to dispose of garbage.

8. Maputo - Mozambique

Maputo is the capital and the largest city of Mozambique located on the bank of Indian Ocean. It is suffering from lack of sanitation processes - specially the lack of a solid waste removal system as well as sewage treatment has created difficulties for people over there. Huge garbage dumps and piles of garbage seem scattered in the streets, and the sewage in the river can be seen.

9. Mumbai - India

Mumbai is one of the most polluted cities of the world so you can see piles of garbage in various streets of the city. It is also considered to be one of the busiest and crowded cities of the world. There are places in the city where you would perhaps not want to go due to stink that comes from filthy garbage scattered over there. The pollution in the areas is massive and is spoiling the beauty of the city on daily basis.

10. New Delhi - India

my advice is, stay clean if you don't want to get sick! start cleaning from your own self, then you can proceed to other things. :)