Fluorocarbon is manufactured using a process similar to that for making nylon fishing line. As far as I could determine, the only manufacturer of fluorocarbon fishing line in the United States is Pure Fishing (formerly Berkley). I talked to Dan Foote, quality improvement engineer, who said that only if fluorocarbon is burned will it produce a toxic material, which is hydrogen fluoride. He also said that unlike monofilament, fluorocarbon doesn't break down as quickly when exposed to sunlight, and it should not be thrown away. Pure Fishing has recycle bins available at many tackle shops for those who wish to discard unwanted fluorocarbon fishing line.