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What are the Connections between Mercury and CFLs?

Using CFLs (and other fluorescent bulbs) instead of incandescent bulbs reduces the amount of mercury released into the environment

CFLs contain very small amounts of mercury

  • Small amounts of mercury can be released into the environment when CFLs break, or if they are improperly disposed of at the end of their useful lives.
  • Mercury, an essential part of CFLs, allows a bulb to be an efficient light source.
  • On average, CFLs contain about four milligrams of mercury sealed within the glass tubing. By comparison, older thermometers contain about 500 milligrams of mercury – an amount equal to the mercury in over 100 CFLs.
  • Manufacturers of fluorescent lighting products are working to reduce the amount of mercury content in CFLs.
  • No mercury is released when the bulbs are intact (i.e., not broken) or in use, but mercury vapor and very small beads of mercury can be released when a CFL is broken.