If you are interested in knowing what the top ten most polluted places are according to the Blacksmith Institute, click here. These places are located in Ukraine (1), Russia (3), Dominican Republic (1), Zambia (1), Peru (1), China (1), Kyrgyzstan (1), and India (1). Some of these places, such as Chernobyl, have been polluted for decades. None of these countries are in the OECD.
To some extent, this reflects the idea of an environmental Kuznet curve. Poor countries are polluted because a clean environment is a superior good that people desire once they have enough food on the table and they can produce a surplus fund. So as poor countries become richer, pollution increases until it reverses. Although the idea that there is an immutable relationship between income and the environment is most likely specious, for there isn’t any such thing in economics. It is however, possible that historically many countries have seen such a relationship at work. See the Wikipedia entry on the subject.