International treaties on trade and global pollution

The paper shows that global pollution need not rise under free trade in goods and/or emissions even in the complete absence of income effects. Differences in environmental concerns across the countries lead to differences in the pollution intensity of production and, thus, generate the possibility of increasing world output and income without increasing the world pollution by shifting the production of the polluting good from the country with higher pollution intensity of production to the country with lower one. We show that free trade in goods and/or emissions can induce precisely such a shifting of production with the country with greater environmental concern exporting the polluting good. The paper also demonstrates the possibility of a first-best international treaty on global pollution in which each country or group of countries is better-off.