All CFLs contain mercury, typically about 4 mg. Some manufacturers have reduced the amount to as little as 1 mg in some types of CFLs, and more manufacturers are following suit. Today, very few household products contain any mercury. Before the 1980s you could find mercury in paint, pesticides, dental fillings and fever thermometers.
A show of hands – who loved their high school chemistry class? Do you still remember the elements in the periodic table? Quick – what’s the symbol for Iron? How about Hydrogen?
OK. Those are easy: Fe and H.
What about Prometheum? or Ytterbium?