Check out the recent ASIL Insight by Julia Qin on the June 2007 "'green' decision" in Brazil – Measures Affecting Imports of Retreaded Tyres.
As Qin (left) explains, the European Communities had brought a challenge against a Brazilian law that bans importation of already-used-but-retreaded tires (right), based on the reasoning that the retreads have a shorter lifespan and so will find their way even sooner into waste heaps where they "create health and enivronmental hazards by providing breeding grounds for mosquite-borne diseases," and further "caus[e] tyre fires that are difficult to control." A panel of the World Trade Organization agreed, perhaps more so than Brazil wished: the panel "effectively directed" Brazil to extend the ban to imports of such tires from countries outside Europe; most notably, MERCOSUR neighbors that'd been permitted to sell the tires in Brazil.
In Qin's view the Brazil - Tyres decision could "become a milestone in WTO jurisprudence on trade and the environment" -- if, that is, it survives review by the WTO's Appellate Body.