Compact Fluorescent Lightbulb (CFL), Mercury and Proper Disposal

If every home in America replaced just one incandescent lightbulb with an ENERGY STAR®-qualified Compact Fluorescent Lightbulb (CFL), in one year it would save enough energy to light more than 3 million homes and prevent greenhouse gas emissions equivalent to those of more than 800,000 cars.  

Replacing energy-wasting incandescent lightbulbs with energy-saving compact fluorescent lightbulbs is an effective, accessible change that every American should make to reduce energy use at home and prevent greenhouse gas emissions that contribute to global climate change.


Mercury (Hg on the periodic table) is an element found naturally in the environment. Mercury emissions in the air can come from both natural and man-made sources. Coal-fired power plants are the largest man-made source because mercury that naturally exists in coal is released into the air when coal is burned to make electricity. Coal-fired power generation accounts for roughly 40 percent of the mercury emissions in the United States. The use of CFLs reduces power demand, which helps reduce mercury emissions from power plants.

Facts about CFLs and Mercury

CFLs contain a very small amount of mercury sealed within the glass tubing – an average of 4 milligrams – about the amount that would cover the tip of a ballpoint pen. By comparison, older thermometers contain about 500 milligrams of mercury – an amount equal to the mercury in 125 CFLs. Mercury is an essential part of CFL technology; it allows the bulb to be an energy-efficient light source. No mercury is released when the bulbs are intact (not broken) or in use. 

Most lightbulb manufacturers have reduced mercury in their fluorescent lighting products. Thanks to technological advances and a commitment from members of the National Electrical Manufacturers Association, the average mercury content in CFLs has dropped at least 20 percent in the past year. Some manufacturers have even made further reductions, dropping mercury content to 1.4 -2.5 milligrams per lightbulb.

Because CFLs help to reduce greenhouse gases, other pollutants associated with electricity production and landfill waste (because the bulbs last ten times longer), they are clearly the environmental winner when compared to traditional incandescent lightbulbs.

What precautions should I take when using CFLs in my home?

CFLs are made of glass and can break if dropped or roughly handled. Be careful when removing the bulb from its packaging, installing it, or replacing it. Always screw and unscrew the light bulb by its base (not the glass), and never forcefully twist the CFL into a light socket. If a CFL breaks in your home, follow these clean-up recommendations.

Where should I dispose of my CFLs?

The U.S. Environmental Protection Agency recommends that consumers take advantage of local recycling options available for CFLs. The EPA is working with CFL manufacturers and major U.S. retailers to expand recycling and disposal options. Consumers should contact their local municipal solid waste agency directly, or go to www.epa.gov/bulbrecycling or http://earth911.com to identify local recycling options.

Connecticut solutions for recycling CFLs