about this and you'll get a dozen different opinions.
CRT monitors generate an Electro-magnetic field which is necessary in order to focus the electrons on the back of the screen, and when you sit in front of the screen you are immersed in this field. Whether or not you are being harmed in this way is a matter of debate, but there is certainly a body of opinion to suggest that long-term exposure to EMF radiation may be harmful.
The problem is made worse by the fact that it isn't only CRT screens which produce EMF, all kinds of electronic devices are doing it, and that's what some experts think is the real problem - we're being exposed to many differnet sources all the time. Chief among the suspects of late has been the mobile phone, and there's been a good deal of talk about the dangers of using these over prolonged periods.
The jury's still out on EMF radiation, and it would be a foolish person who said that there was no need for concern. We really just don't know, and in a way that may be a good thing, because non of us can avoid some exposure to the background radiation that's all around us in a modern society.
The best advice I can pass on is that you do not sit too close to your screens, and that you avoid working at the back of them when they're switched on - the radiation field is stronger there.