Recycle used CFLs at your local Home Depot, IKEA or check Earth911.org for drop-off locations in your zip code. If your state permits you to put used or broken CFLs in the garbage, seal the bulb in two plastic bags and put it in the outside trash. Don't incinerate, as CFLs contain a small amount of toxic mercury, an average of about 5 milligrams, which would get released into the air.