Trade liberalization and pollution havens

U.S. Presidential Executive Order 13141 commits the United States to a careful assessment and consideration of the environmental impacts of trade agreements. The most direct mechanism through which trade liberalization would affect environmental quality in the U.S. is through the composition of industries. Freer trade means greater specialization, increasing the concentration of polluting industries in some countries and decreasing it in others. We begin by documenting the substantial shift in U.S. manufacturing toward cleaner industries from 1972 to 1994. We then use annual industry-level data on imports to the U.S. to examine whether this compositional shift can be traced to the significant trade liberalization that occurred over the same time period, and we conclude that no such connection exists. A shift toward cleaner industries has also occurred among U.S. imports, and we find no evidence that pollution-intensive industries have been disproportionately affected by the tariff changes.