Are international environmental policies effective? : the case of the Rotterdam and the Stockholm Conventions

This paper is the first to estimate the effect of two international agreements (Rotterdam Convention, RC, and the Stockholm Convention, SC) in reducing trade in hazardous substances. We estimate the effects of ratification of these agreements on imports of the affected products putting emphasis in the flows from developed countries (OECD) to developing countries (non-OECD) to capture pollution deviation. We use product level data to identify the goods subject to the conventions and the identification strategy relies on the use of difference-in-difference techniques in a panel data framework. We find that when the exporter ratifies the RC and the flow is from OECD to non-OECD countries, a significant reduction of imports in hazardous chemicals is observed after ratification. The magnitude of the effect is a cumulative decrease in imports of about 7 percent. In the case of the SC, the results show significant reductions in trade shipments from OECD to non-OECD countries in persistent organic pollutants for non-OECD importers that have ratified the convention. We observe a reduction of around 16 percent, more than double the effect found for the RC, which was expected due to the different obligations imposed by the respective conventions.