Compact Fluorescent Light Bulbs: Mercury Warning

Many environmental groups are pushing people to replace all the light bulbs in their homes with Compact Fluorescent Light (CFL) bulbs with similar lumen yields as their current incandescent light bulbs. This would definitely cut down on carbon dioxide emissions since much less electricity is needed to drive a CFL bulb than an equivalent incandescent bulb. A 25 Watt CFL bulb can produce as much light as a 100 Watt incandescent light bulb with one quarter the amount of electricity.

This sounds great with only some complaints from people who do not want to pay for the significantly more expensive CFL bulbs or have problems fitting them into existing light fixtures.

Lately a new warning is being issued which is environmental in nature. CFL bulbs contain mercury. Mercury is a neurotoxin which is already causing worries due to high concentrations in fish such as swordfish, tuna and other large predatory species which tend to accumulate the mercury from their prey. The prey fish were contaminated from land based runoff sources including landfill, mining operations and industrial pollution.

The question is just how dangerous the mercury from CFL bulbs is when added to current ambient mercury. To find out the answer to this we do have some data which will help to determine just how much increased risk are we dealing with.

First the average CFL bulb contains 5 milligrams of mercury. This is not much, about the size of a ball in a ball point pen tip. This is safe as long as the bulb keeps its integrity. If the bulb breaks the mercury is released into the environment. Household bulbs come in multi-packs which are tricky to open and increase the risk of breakage. If one or more bulbs shatter in your home do not use a vacuum cleaner to remove the remains. A vacuum will suck in the mercury and turn it into an aerosol spray. This is the most dangerous form of mercury since it can be inhaled directly by people.

There is no need to panic if a CFL bulb bursts. Call your local poison control center and they will give you directions to remediate the pollution a broken bulb can cause. A good precaution is to leave the room where the bulb broke for at least 15 minutes.

A larger problem is discarded bulbs put into regular trash. According to Wikipedia there were 270,000,000 CFL bulbs dumped in landfills in 2007. This equates to 3,013 pounds of mercury which will only increase as the use of these bulbs increases. Once in the landfill the bulbs will almost surely break releasing the mercury they contain.

The question is will the trade off of less greenhouse gasses produced to create electricity for the less efficient incandescent bulbs outweigh the additional mercury in the environment from the CFL bulbs?

A comprehensive recycling program for CFL bulbs would swing the environmental benefits toward their usage. However, very few states require this be done at the present time. Significantly more research must be done relating to the disposal of CFL bulbs before we can tell whether they are an ecological boon or an ecological disaster. Most likely some other light source such as super bright LEDs will eventually replace both CFLs and incandescent bulbs within a few years.