A foamy threat to ozone

U.S. residents junk some 8 million refrigerators annually. The unrecyclable components, including polyurethane foam insulation, often go into community landfills. Through the early 1990s, this foam usually incorporated chlorofluorocarbon-11 (CFC-11), a gas that destroys stratospheric ozone. Environmental scientists have now found that the speed with which this now-banned chlorofluorocarbon escapes into air depends on the way waste managers handle the discarded foam.