Mercury and energy-saving light bulbs
The Climate and Pollution Agency (formerly SFT) is committed to reducing emissions of mercury and mercury compounds as they are toxic.
In 2008, the EU prohibited almost all uses of mercury. However, common incandescent light bulbs will soon become unavailable because they generate more heat than light. These are being replaced by energy-saving light bulbs, which contain mercury.
– Why is mercury used in light bulbs?
Fluorescent tubes and bulbs need small amounts of mercury to work, i.e. mercury vapours that are contained within the lamp’s gas discharge tube, at low pressure and with a temperature of about 40 ºC when the lamp is switched on (the boiling point of mercury is 357 ºC). The mercury condenses as particles when the lamp is switched off. As the lamps age, some mercury is absorbed in the coating on the inside of the glass.
In a few years, LED-based light sources will become more affordable and these do not contain mercury. Until then, we must use light sources that each contain 2-5 milligrams of metallic mercury. This is not a lot but is enough that we should take some simple precautions if a fluorescent tube or a bulb shatters.
– What should you do if a mercury-containing bulb shatters?
- Open the window to air the room.
- Gather together the bits of the bulb as thoroughly as possible.
- Visible particles and glass residue can be picked up using a piece of tape.
- Use a dustpan and brush and wipe thoroughly with a damp cloth.
- Both the cloth and glass should be placed in a sealable plastic bag for delivery to an approved waste recycling facility (this should be placed outdoors until disposal).
- Loose rugs can be taken outside and beaten.
- The room should be aired for 15 minutes after cleaning.
– What do you do if your energy-saving light bulbs are not broken?
All used light bulbs, whether they are broken or not, should be delivered to an approved waste recycling facility.
– What about the vacuum cleaner?
Vacuuming can help to spread the mercury residue, and therefore one should avoid it if the floor has a smooth surface without cracks. Do you have carpets or cracks in the floor? It is still best to use the vacuum cleaner, so that all the glass residue and mercury is removed.
Mercury particles may remain in the vacuum cleaner, so after use you should let the vacuum cleaner run for half an hour outdoors before changing the dust bag. The vacuum cleaner bag should be disposed with the other waste from the clean-up. In addition, you can remove the vacuum hose and rinse the inside well with water.
– No reason to panic
There is very little mercury in a bulb, and it is difficult to imagine how exposure may be hazardous. However, it is a good rule to dispose of all the glass and the mercury residue.
The mercury is actually most dangerous when it comes out in nature, because it is converted to organic mercury compounds which are ingested particularly by fish. These mercury compounds are highly toxic and can find their way into certain foodstuffs. It is therefore important that mercury is not released into the environment.
– Is it wise to shake out the rugs if mercury is most harmful in nature?
“This is a very small amount and even 2 mg of mercury in the garden is very little. Safe collection and deposition of mercury-containing waste applies mostly to somewhat larger quantities” said Gunnar Brunborg at the Norwegian Institute of Public Health.