By The Guardian, January 21, 2008 

The environmental damage caused to developing nations by the world's richest countries amounts to more than the entire third world debt of $1.8 trillion, according to the first systematic global analysis of the ecological damage imposed by rich countries.

The study found that there are huge disparities in the ecological footprint inflicted by rich and poor countries on the rest of the world because of differences in consumption. The authors say that the west's high living standards are maintained in part through the huge unrecognised ecological debts it has built up with developing countries.

http://www.guardian.co.uk/science/2008/jan/21/environmental.debt1