The Mercury Myth: How Much Mercury Do CFLs Actually Contain?

By Matthew Van Dusen, Txchnologist

It’s a zombie myth that just won’t stay down: Compact Fluorescent Lamps contain toxic mercury. There is about as much truth to that statement as there is mercury in CFLS — which is to say, trace amounts. CFLs do contain mercury, but in quantities so small that breaking one exposes you, in most cases, to less mercury than eating tuna fish (see below). We consulted the EPA and contacted a lighting specialist from General Electric, which sponsors this magazine [Txchnologist], in order to take on the issue of mercury in CFLs.

CFL bulbs

image via Shutterstock

How does mercury help produce light in CFLs?

CFLs are glass tubes that are filled with argon gas and mercury vapor. When an electric current passes through the tube, the mercury emits ultraviolet light that excites a phosphor coating on the tube. The coating then emits light.

Are we talking about high levels of mercury?

No. And the amount of mercury in CFLs has dropped steadily since they first made inroads into the market 15-20 years ago. As recently as 2007, CFLs contained about 5 milligrams, enough to cover a ballpoint pen tip. Since then, regulations in the European Union, which have also been adopted in California and other areas, have mandated that the amount of mercury in CFLs be limited to 3.5 mg by 2012 and 2.5 mg by 2013.

GE spiral CFLs use an even smaller amount: 0.8-0.9 mg of mercury. Sándor Lukács, the CFL systems manager for GE Appliance & Lighting, said the company decided to rapidly cut the mercury content of its CFLS in the 1990s. “To put it in perspective,” Lukács said, “when I was a little child, I had a thermometer that had 1,000 times more mercury than the current CFLs.”

Is there a replacement for mercury?

Scientists both inside and outside GE have used amalgams, an alloy containing mercury and one or more metals that can release mercury for discharge (amalgams have also been used in fillings). Lukács said GE researchers found that lamps without mercury had less efficacy, a measure of how well a lamp produces visible light, but some CFLs use amalgams as an alternative.

How do you dispose a CFL?

It’s against the law in several states – including California, New York and Connecticut – to throw CFLs in the garbage and it’s a bad idea everywhere. In the U.S., more than 1,700 Lowe’s stores take used CFLs and other recycling facilities can be found on In the European Union requires, the cost of recycling is built into the purchase price and retailers must collect them from consumers

What happens to the mercury when the bulbs are disposed?

Mercury is in two forms in the lamp, solid and vapor. During the life of the bulb, the glass in the lamp consumes some of the mercury – up to 0.4 mg depending on the age of the lamp, Lukács said. Both the solid mercury and the consumed mercury can be recovered and processed for reuse in recycling facilities.

How do you clean up a broken CFL?

There’s no need to call the hazmat team. Still, the D.E.P. recommends leaving the room and ventilating it for 5-10 minutes. Then sweep up the broken glass and put it in a glass jar or a sealable plastic bag. The EPA advises against vacuuming broken bulbs because it can spread mercury vapor.

How much mercury are you exposed to when a CFL breaks versus, say, eating a tuna fish sandwich?

You may have missed this one, but an essay in the August 2009 issue (PDF) of LD+A, the magazine of the Illuminating Engineering Society of America, argued that people are exposed to far greater amounts of mercury by eating tuna fish. A typical 6 oz. fish sandwich contains 48 micrograms of mercury (that’s 0.048 mg), according to the U.S. Department of Health and Human Services. If you knock over a lamp and a CFL breaks, it will typically results in a dose of 0.07 micrograms (that’s 0.0007 mg) of mercury, according to scenarios assessed by the Maine Department of Environmental Protection. According to the authors, these numbers show that the issue of dangerous mercury in CFLs is “One Big Fish Story.”

Editor’s Note: This story comes to us as a cross post courtesy of Txchnologist. Author credit goes to Matthew Van Dusen.


  • Reply October 6, 2011


    I picked up on this article, too I think the EPA takes a lot of the blame by being overly alarming in its advice on cleaning up broken CFLs.

    • Reply August 16, 2014


      so there’s 0.048mg of mercury in 6oz of tuna and 5.000mg of mercury in a CFL.
      sound’s like a lot to me…

      • Reply March 21, 2015

        Matthew Whited

        They used the wrong notation. it should have said .048g for tuna and .0007g for the CFL.

  • Reply October 7, 2011


    Yeah Germany completely banned cfls I’d like to know there reasons .

    • Reply October 18, 2011

      John Smith

      Germany is a pretty progressive nation, their government isn’t full of pigheaded anti-technology types so they must have their reasons, probably eco.nnIf you really want to avoid CFLs, have tubular skylights installed in your house.u00a0 Cuts down on bulb usage.

  • Reply October 9, 2011


    I have a snow capped mountain in my yard here in Florida I’ll sell you NINO real cheap.Nice try but I won’t and haven’t bought these pieces of garbage that don’t last as long as you and GEs BS say they will and cost way more then they should.So go pedal your lies else where.I don’t buy anything with the GE logo on it and our we have changed the words to theirs tou00a0 GEu00a0 WE BRING EVIL TO LIGHT.

  • Reply October 10, 2011

    Taj Mahal india

    CFLs are safe to use in your home. No mercury is released when the bulbsn are in use and they pose no danger to you or your family when used nproperly. However, CFLs are made of glass tubing and can break if ndropped or roughly handled.

  • Reply October 13, 2011


    How many people just throw these light bulbs in the garbage, and into the water supply we all share?!? u00a0Your article doesn’t address this problem at all. u00a0Trace amounts of a neurotoxin, multiplied by how many we throw out that then get into our water supply, equals more neurotoxins in our environment and bodies, plain and simple.

  • Reply October 18, 2011

    John Smith

    I wished GE would make glass shrouded bulbs like Phllips brand.u00a0 I’m not big on Phillips because the CFL light is a rather odd color, not quite warm white and somewhat bluish.nI prefer GE because the color is better and they start up much faster and don’t have a long warm up time.u00a0u00a0 The bulbs with a glass capsule are nearly impossible to shatter.u00a0u00a0 Bulbs with exposed spirals are very delicate and must be handled carefully.u00a0 They can break even if dropped on a hard surface from about 2 inches.

  • Reply January 18, 2012


    Oh well it does not worry me as I am already dead, according to these envirofreaks. When I was in high school the Physics teachers had us all rolling globs of pure mercury around in the palms of our hands to demonstrate surface tension. I survived – thrived even – as did the rest of us. This is just another piece of enviroloonie silliness. u00a0

    • Reply May 23, 2014


      And today you are mad as a hatter!

  • Reply December 8, 2013


    Good. I just broke a CFL and the EPA website was freaking me out and made me think I was going to freaking die. Nice to know I’m okay.

  • Reply May 26, 2014


    How can we check the contents of mercury in CFL Glass Shell.?

  • Reply February 11, 2015

    David Hammond

    CFLs contains elemental mercury, while fish contains methyl
    mercury. They are not the same and have different properties. Elemental mercury
    gives off mercury vapor which is inhaled. The Lowest Observed Adverse Effect
    Level is 9,000 ng/m3. There is no No Adverse Observed Effect level. – that is
    there is no level of exposure to mercury vapor which has been shown to be safe.
    Tests by the Maine Department of Environmental Protection found that broken
    CFLs could result in a mercury air concentration of up to 50,000 ng/m3. The
    guideline for ambient air is 300 ng/m3.

    If CFLs are broken on carpet, the carpet should be removed and disposed of as
    the mercury cannot be removed effectively. If mercury spills are not cleaned up
    properly, mercury vapor can continue to be released for many months. Young
    children are particularly at risk in this situation.

    There is at least one case of mercury poisoning from light bulbs – a 23 month
    old baby developed acrodynia after being exposed to mercury from broken
    fluorescent light bulbs.

    Tunnessen, W. W., McMahon, K. J., & Baser, M. (1987). Acrodynia: exposure
    to mercury from fluorescent light bulbs. Pediatrics, 79(5), 786-789.

    David Hammond

    Author: Mercury Poisoning: The Undiagnosed Epidemic

  • Reply February 26, 2015


    So let me see if I’ve got this right. The amount of mercury is very small, but it is still dangerous to throw CFL light bulbs in the trash? If one breaks, we should air out the house 10-15 minutes and be very careful about cleaning it up? Either somebody’s being overly cautious (several state governments?) or else there is a very real and present danger, regardless of how little mercury is present. Maybe the government should stop trying to mandate what kinds of lights we use, as they just seem to be confusing the issue and increasing consumer risks. After all, who is paying for the electricity used? Of course, the government regulates the power grid, too, so they don’t really know how to respond to economic incentives.

    • Reply February 16, 2016

      Frank Lively

      It;s also recommended that we leave the room for 10-15 minutes after eating a tuna sandwich.

  • Reply September 29, 2016


    Mercury doesn’t kill you, generally. It causes neurological damage. The fact that tuna has a similar order of magnitude of Hg is not a reflection of Hg’s safety, but a reflection of just how contaminated our tuna has become. A pregnant woman who eats more than 1/3 of a serving of tuna a week is exceeding the health risk level for them/their child. 1 serving a week for an adult.

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