CFL bulbs contain mercury and when they break in your home a tiny amount of mercury will be released and become a more or less permanent part of your environment.
Here’s a little taste of what Health Canada has to say about the dangers of mercury: If mercury is burned, heated, sprinkled or spilled in the home, a poisonous gas can be produced, requiring a clean-up procedure.

Your first instinct when you break one of those coiled CFL light bulbs will be to get out the vacuum cleaner. Don’t. Here’s what Health Canada suggests: The amount of mercury found in household products does not usually lead to serious health problems and can often be cleaned up without the help of a trained professional. However, even small spills should be treated as hazardous and cleaned up with caution. Remember to report these spills to the local environmental health authorities. Depending on the size of the spill, hiring a Contractor to monitor mercury levels in air, and to conduct a professional clean-up, may be advisable. There are also commercially available small mercury spill kits that can be obtained. Never vacuum a mercury spill with a household vacuum cleaner. It will increase the vaporization of the mercury.
A few helpful hints to remember are: •Do not put contaminated items in the washing machine; •Do not vacuum the spill; •Do not use a broom or a brush; •Do not pour mercury down the drain; and Do not throw mercury or contaminated items in the garbage.
Incandescent bulbs have been banned from the marketplace and are in the process of being phased out. They do cast a very palatable light, which is probably why they technology to replace them has been slow to develop.
The cheapest way to replace incadescent bulbs is to switch to CFLs and you will see a lot of propaganda from BC Hydro aimed at helping you make the switch. The only rational explanation for promoting CFLs is that they are cheap, so cheap that people will balk at the price of LEDs, which are a far better solution.
LEDs are more efficient, longer lasting and may throw a better quality of light. Today Environment Canada provided yet another good reason not to buy CFLs and instead go straight to LED lights. Canada’s mercury waste facilities are not ready for the coming onslaught of mercury-laden CFL bulbs as they burn out and break.
With no effective way to collect the bulbs, most will go to landfill where they will begin to poison the groundwater, rivers and eventually our oceans.
Even the few bulbs that are collected are unlikely to be rendered harmless. There are no facilities in Canada to extract mercury from waste. How long the United States will allow Canadian toxic waste to be shipped across the border is anybody’s guess.