[Thalia (OP)]

I just learned that the CFLs have small amounts of mercury and emit high UV radiation.
If they break they release mercury vapor into your home and if they aren't disposed of properly will end up in the garbage and our landfills and eventually our water supply.

There are no instructions on the packaging about their disposal and here in Europe no other options since incandescent light bulbs are being phased out...

Just read an article on google news here:
Compact fluorescent light bulbs (CFLs) serious dangers and alternatives
  newbielink:http://www.examiner.com/holistic-science-spirit-in-national/compact-fluorescent-light-bulbs-cfls-serious-dangers-and-alternatives#ixzz1CeJctW5c [nonactive]

[Bored chemist]

There's a very small amount of mercury in them.
There's a lot more mercury in my teeth than in all the lightbulbs I will ever buy.
Running a normal incandescent lamp takes more power than running a CFL. Since there's a small amount of mercury in the coal that is used to generate the power that runs the bulb you have to compare the amount of mercury that gets into the air from the lamp with the amount of mercury that would have got into the air from burning coal to run the old lamp.
It's a close race.

There are rules about how much UV these lamps are permitted to produce. It's small- too small to do any harm. In any event, people have a fair degree of resistance to UV light. We have to because it's present in sunlight.

Personally, I am much more concerned about the fact that they take a few seconds to come one and minutes to warm up than about the mercury.
I'm hoping to be able to buy LED lamps to replace my lights with soon.
And, for the record, I know that most LEDs have arsenic in them; I don't plan to eat them.

[Geezer]

Personally, I am much more concerned about the fact that they take a few seconds to come one and minutes to warm up

Me too. For that reason I tend to leave them turned on more than would have done with incandescent bulbs, so I'm probably not saving as much energy as I might like to think. Unfortunately, it would be bad investment for me to buy LEDs. I doubt that I could outlive them.

[peppercorn]

Unfortunately, it would be bad investment for me to buy LEDs. I doubt that I could outlive them.

Leave them in your will to your children []

[CliffordK]

There is a lot of debate on the efficiency of LED vs CF.

The LED tends to give a focused beam (good for a flash-light).
The CF lights tend to give a broadcast beam, good for room lighting.

[Mazurka]

We have a mix of CFL and LED and "eco"halogen(*) GU10 (Halogen spotlights) in our Kitchen.

I prefer the light from the CFL's, but they take ages to warm up and it is a little like being in a cave until they do.   

One of the LED units has failed in less than 18 months and I might get round to sending it back one day.

(* this is eco in the sense of being  a rather dim 35W rather than 50W)

I would also add to BC's analysis, the presence of mercury in landfill leachate does not pose a particular risk to the environment in western coutnries.  This is mainly due to the very high engineering standards now used, with multiple barriers (liners) between the site and the surrounding environment.  These plastic membrane liners are geophysically tested to detect leaks and will be backed up with use a low permeabillity geological barrier - i.e. enegineerd clay or artifical equivalent and a leachate management system that prevents too great a head of liquid acting on the lining system.