Light-bulb Liars II: Mercury and CFLs

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By Elisa Wood

July 16, 2009

The Washington Times ran a commentary July 11 that took a swipe at compact fluorescent lights. Titled “Light-bulb liars,” the article warns that broken CFLs are an “environment disaster in your family room” that “could poison the dog, the kid and the wall-to-wall rug.”

To underscore the gravity of CFL dangers, the article then takes us through the Environmental Protection Agency’s step-by-step mercury clean-up advice.

Here are a few things the article fails to say about CFLs, that points out.

*True, they contain mercury, but a very small amount. They average 4 milligrams, compared with 500 milligrams in the old mercury-based thermometers, an amount equal to 125 CFLs.

*Advancements in CFL technology are reducing their mercury content. Some have mercury content as low as 1.4 to 2.5 milligrams.

*Coal-fired electric plants create a heck of a lot more mercury. CFLs are more efficient than conventional light-bulbs. So when we use CFLs we use less electricity, meaning grid operators and utilities can fire up coal-fired generators less frequently.  If all of the CFLS sold in 2007 ended up in a landfill, they would deposit 0.16 metric tons of mercury. In contrast, coal plants emit 104 metric tons of mercury annually.

The article also points out that CFLs are more expensive than conventional incandescent lights, but fails to say that they continue to operate far longer.

After I finished reading the Washington Times commentary, my eyes went back up to the title: “Light-bulb Liars.” Now the Times wasn’t referring to itself, was it? Okay, to say the paper lied might be a little harsh, but the article certainly engaged in hyperbole and sins of omission.

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Elisa Wood About Elisa Wood

Elisa Wood is the chief editor of She has been writing about energy for more than two decades for top industry publications. Her work also has been picked up by CNN, the New York Times, Reuters, the Wall Street Journal Online and the Washington Post.


  1. About : CFL mercury versus Coal Power mercury, in the comments above

    CFL mercury is a much bigger problem.


    Coal power mercury was only ever a problem where untreated coal was used, and dominated

    Also emissions can now easily be treated, with new injection and photochemical techniques as well as so-called scrubbers.

    Not only that, emissions will drastically fall in the next few years, as EPA themselves maintain:
    2005 decision, 90% power station mercury emission reduction by 2018, (phase 1 = 21% reduction by 2010, phase 2 = 69% further reduction by 2018) , confirmed by new administrator Lisa Jackson.

    For more see

    In a nutshell:
    1. We know where the ever decreasing local coal power stations chimneys are and we can treat their emissions with ever increasing efficiency at lower costs.
    2. Compare that with billions of scattered broken lights on dump sites, when we do not know where the broken lights will be, and so we can’t do anything about them.

    (deposit-refund or free collection schemes would be a good idea, but have not prevented most CFLs in Europe being thrown away with other household waste)

  2. John Spencer says:

    Mercury of any sort is not good for sure, but I have some other thoughts about power plant emissions of mercury.

    Coal fired boilers do have scrubbers, electrostatic precipitators, or chemical wet scrubbers to get 90% of the ash, which contains the mercury, out of the flue gas. That’s fine, and great strides have been made in improving the efficiency of these devices.

    But there is a problem. A lot of the ash from burning coal simply passes through the grates of the boiler into ash collection systems, like a dumpster. The ash from the flue gases is first passed through dry removal devices like cyclone separators, bag houses, and electrostatic precipitators. This removed dry ash also ends up in the same collection systems as the ash from the grates. Having operated boilers.

    This ash has to go somewhere. Sometimes, and generally in times gone by, this ash was simply put in piles next to or near the coal fired plants. To keep the dust down, often times the ash we either mixed with water or put into ponds, and then landfilled wet.

    Today, the ash is considered a toxic waste and must be sent to an approved toxic waste landfill, where techniques like mixing with concrete are deployed.

    However, recently I have seen where local municipalities are actually taking some of the ash from the power plants, and mixing it with the salt they use for roads during the winter. It was even touted as a great way for the local city to reduce the cost of taking care of the roads since salt prices had risen 5 fold in the past couple of years. They were claiming that this was a savings both to the city and to the power plant’s owner who could now reduce their costly landfill expense.

    Do you see a problem with this? I do, big time. The ash which contains the mercury from the coal, is now spread in a thin layer all over our streets where after thousands of cars run over it turns into a fine dust that blows in the wind all over the place, including into our lungs, onto playgrounds, front yards, all over toys etc.

    Coal contains mercury. Though 90% might be removed from the air stream from a boiler, 100% of the mercury from coal ends up in the environment in one form or another. Don’t be fooled. Power plants try very hard to contain their ash, but having worked at an operation that burned solid fuels, a lot of ash ends up all over the place, not in the secured landfill.

    I also want to raise another point. Coal contains mercury. It also contains other very toxic materials, like uranium, thorium, cadmium, and lead to varying degrees. These too are knows carcinogens, all ending up in the environment with coal combustion.

    As the article states, if all the CFL’s were broken, and all the mercury vapor were released into the air, 0.16 tons of mercury would be released. Coal plants emit 104 tons of mercury into the air now. CFL’s mercury emissions are miniscule in comparison. If the bulb is properly disposed of, little mercury is released if any at all.

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