Conservations groups recently released this year's list of the 10 worst polluted placed in the world. Experts from Johns Hopkins University, Harvard University, MIT, Mount Sinai Hospital and other groups devised the listing criteria, which focused on pollution's impact on human health, especially that of children.

Here is the group's list in alphabetical order.

Sumgayit, Azerbaijan
Linfen, China
Tianying, China
Sukinda, India
Vapi, India
La Oroya, Peru
Dzerzhinsk, Russia
Norilsk, Russia
Chernobyl, Ukraine
Kabwe, Zambia

The sites were chosen from a database of over 400 locations. The group also released a so-called "Dirty Thirty" list of the 30 most polluted locations on Earth. More weight was given to the toxicity of the listed pollutant and the number of people at risk. Visit www.worstpolluted.com for more details.