Most CFLs contain 3–5 mg of mercury per bulb, with the eco-friendly bulbs containing as little as 1 mg. Even in small amounts mercury is still poisonous and creates a potential risk for landfills and waste incinerators where it can contribute to air and water pollution. Thus, the EPA classifies fluorescent lamps and CFLs as hazardous waste, and recommends that they be segregated from common waste for safe disposal and recycling.

Home Depot – CFLs ONLY, no tubes
952 Richards Ave, Santa Fe
(505) 424-9463
Lowe’s Home Improvement – CFLs ONLY, no tubes
3458 Zafarano Road, Santa Fe
(505) 819-4080
Ideally, place your old tubes in the same box in which they were purchased. If that is long gone, place your used CFLs in a sturdy container (i.e. box or bucket) with a lid. Label your container and keep it in a safe spot, away from children and pets. If you can’t find a large enough box, try to bring them to a collection center soon after changing them out. When transporting the container, put it in your trunk, back seat, or wrap them so they won’t roll around or tip over.
If your CFL or fluorescent tube breaks, you should follow these clean up procedures as recommended by the EPA:

• Air out the room for 5-10 minutes by opening a window or door to the outdoors.
• Shut off the central forced air heating/air-conditioning system, if you have one.
• Collect materials needed to clean up broken bulb:
During Cleanup 
• Place cleanup materials in a sealable container.
After Cleanup 
• Promptly place all bulb debris and cleanup materials outdoors in a trash container or protected area until materials can be disposed of properly. Avoid leaving any bulb fragments or cleanup materials indoors.
• If practical, continue to air out the room where the bulb was broken and leave the heating/air conditioning system shut off for several hours.
For more information, visit EPA’s advice on Mercury Spills
If CFLs contain mercury, which can be bad for the environment and my health if not properly recycled, then why should I switch from the traditional incandescent light bulb to a more efficient CFL?
In areas with coal-fired power plants, the use of CFLs saves on mercury emissions when compared to the use of incandescent bulbs. This is due to the reduced electrical power demand, reducing in turn the amount of mercury released by coal as it is burned. Coal-fired power plants also emit other heavy metals, sulphur, and carbon dioxide which can be very hazardous to your health. Overall, a CFL uses less energy (roughly 90%) than an incandescent bulb which reduces the emissions at the source.
Read more information on CFLs & Mercury on the EPA’s website.