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MERCURY – TIME TO ACT
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Compact uorescent lamps (CFLs)
Level of mercury per bulb (mg)
Source:
Adopted from European Lamp Companies Federation
→http://www.elcfed.orgUNEP en.lighten, December 2012
Designed by Zoï Environment Network / GRID-Arendal
Global Sales of CFLs (millions)
1,000
2,000
3,000
4,000
5,000
Global CFL Sales
1995
2000
2005
2010
2015
2020
Managing surplus mercury involves collection, stabilization
and safe disposal to isolate it from the biosphere. Stabilizing
mercury offers several benefits: technology is available on an
industrial scale, there is no risk of liquid spillage, vapour pres-
sure is below occupational safety limits, and mercury con-
centrations in leachates are below the threshold for disposal.
Beyond that, the lower commercial value of the stabilized
mercury reduces the risk of theft, and disposal after stabiliza-
tion by binding with sulphur is possible. Several stabilization
technologies exist: chemical transformation into a more sta-
ble, less mobile chemical compound; micro-encapsulation,
the embedding of particles in an impermeable matrix such
as cement; and macro-encapsulation, the covering of waste
material with an impermeable material, for example poly-
ethylene. The fact that stabilized mercury is non-toxic signifi-
cantly helps the search for suitable storage sites. Unlike liquid
mercury, the stabilized form is suitable for storage in landfills
and underground.