In use, all too many construction plastics are toxic in application and outgas harmful vapours, a topic I will deal with more extensively in the next section on indoor air quality. In disposal, these plastics present a major problem, with the recycling rate for construction being even lower than the low 6-7 percent rate for all plastics. There are some major technical problems in recycling plastics, especially composite materials. But even where recycling is technically feasible, there have been substantial collection and separation problems to inhibit it. And almost invariably plastics recycling is downcycling. While it is important to understand the common attributes and problems of oilbased plastics, it is equally important to understand that there are important differences between plastics, and that plastics can have a role in an ecological economy. PVC, however, would not be one of those plastics. Because, as a chlorinated compound, it is considered the most destructive plastic, it is a particular target of the green building and environmental toxics movements, the object of a worldwide campaign to have it banned. Despite its negative impacts, however, such a phase-out is not a straightforward matter since powerful vested interests are arrayed in its defense. Because vinyl is at the nexus of major struggle by and within the green building movement, and also because this strategic position within the petrochemical economy, it is worthwhile to devote some attention here to the PVC issue. PVC (or vinyl) is the only major building material that is an organochlorine, a class of chemicals that has come under increasing scientific and regulatory scrutiny over the last 15 years. An organic compound is a chemical built up around a chain of carbon atoms. Along this carbon skeleton, oxygen and hydrogen atoms are usually arrayed,