The Facts About Mercury in CFLs

MADISON, Wis. (September 25, 2007)

Demand for CFLs has increased over the past several years, leading some consumers to ask questions about mercury levels in CFLs.  While there is a small amount of mercury encased in the base of a CFL, using the bulbs poses no harm to consumers.  In fact, CFLs do not emit mercury when they are intact, in use, properly stored, handled and/or installed.  The truth is CFLs are safe to use and account for fewer mercury emissions than traditional incandescent bulbs.

Mercury and CFLs

Like all fluorescent lamps, CFLs contain a small amount of mercury—an average of 5 milligrams (mg) per bulb.  By comparison, some watch batteries contain 25mg of mercury, and many manual thermostats contain up to 3,000mg. In fact the presence of mercury may be more common than many people realize (See chart below.)

Mercury Content of CFLs vs. Other Common Household Products
Product Amount of Mercury Number of Equivalent CFLs
Compact fluorescent light bulb 5 milligrams 1
Watch battery 25 milligrams 5
Dental amalgams 500 milligrams 100
Home thermometer 500 mg – 2 grams 100 – 400
Float switches in sump pumps 2 grams 400
Tile Thermostat 3 grams 600

The largest source of mercury in our air (about 40 percent in the U.S.) comes from burning coal to produce electricity.  Because CFLs require significantly less electricity than incandescents, they actually contribute to a reduction in net mercury emissions.  This is because a power plant will emit more mercury producing the electricity to light incandescent bulbs than CFLs.

Manufacturers continue to take steps to reduce the amount of mercury used in their fluorescent lighting products, and mercury levels in CFLs are expected to decrease by the end of 2007 thanks to advances in technology and a commitment from the members of the National Electrical Manufacturers Association.
Other CFL Benefits

According to the U.S. Environmental Protection Agency (EPA), if every home in the U.S. replaced just one incandescent light bulb with an ENERGY STAR qualified CFL, we would save enough energy to light more than three million homes and prevent greenhouse gas emissions (which contribute to global climate change) equivalent to those of more than 800,000 cars annually.

CFLs Offer Other Benefits, As Well:

  • Lower energy costs.  Compared to incandescent bulbs, CFLs use up to 75 percent less energy to produce the same amount of light.  Because the average home spends about 20 percent of its electricity on lighting, this can result in significant savings. 
  • Longer life.  Most CFLs last 6,000 to 10,000 hours compared to just 1,000 hours for incandescent bulbs.  This saves consumers both time and money on replacement bulbs and reduces waste.
  • Cooler operation.  CFLs burn cooler, reducing the risk of fire.

Proper Disposal of CFLs

EPA recommends that consumers take advantage of local recycling options, such as recycling centers and transfer stations, to dispose of CFLs.  Many communities schedule household hazardous waste collection events when fluorescent lamps are collected along with paints, pesticides, used motor oil and other materials.  Consumers can also recycle CFLs at retail locations participating in Focus on Energy’s new recycling program.  If there are no recycling options in your area, seal the CFL inside two plastic bags and place it in the outside trash.  CFLs should never be sent to an incinerator. 

Cleanup of Broken CFLs

According to guidelines established by the EPA, you can safely clean up a spill from a broken CFL. The small amount of mercury in a CFL is not likely to cause a health problem, but it should still be cleaned up properly. The following steps can be performed by the general public:

  1. Open a window and leave the room for 15 minutes or more.
  2. Carefully scoop up the fragments and powder with stiff paper or cardboard and place them in a sealed plastic bag.
    • Use disposable rubber gloves, if available (i.e., do not use bare hands). Wipe the area clean with damp paper towels or disposable wet wipes and place them in the plastic bag.
    • Do not use a vacuum or broom to clean up the broken bulb on hard surfaces.
  3. Place all cleanup materials in a second sealed plastic bag.
    • Place the first bag in a second sealed plastic bag and put it in the outdoor trash container or in another outdoor protected area for the next normal trash disposal.
      • Note: some states prohibit such trash disposal and require that broken and unbroken lamps be taken to a local recycling center.
    • Wash your hands after disposing of the bag.
  4. If a fluorescent bulb breaks on a rug or carpet:
    • First, remove all materials you can without using a vacuum cleaner, following the steps above. Sticky tape (such as duct tape) can be used to pick up small pieces and powder.
    • If vacuuming is needed after all visible materials are removed, vacuum the area where the bulb was broken, remove the vacuum bag (or empty and wipe the canister) and put the bag or vacuum debris in two sealed plastic bags in the outdoor trash or protected outdoor location for normal disposal.

Contact Focus on Energy at (800) 762-7077 to learn more about mercury in CFLs and retailers that offer CFL recycling.

About Focus on Energy

Focus on Energy works with eligible Wisconsin residents and businesses to install cost effective energy efficiency and renewable energy projects.  Focus information, resources and financial incentives help to implement projects that otherwise would not get completed, or to complete projects sooner than scheduled.  Its efforts help Wisconsin residents and businesses manage rising energy costs, promote in-state economic development, protect our environment and control the state's growing demand for electricity and natural gas.  For more information call (800) 762-7077 or visit