Ironically, it seems that it's not only those who work with computers who are at risk.
Er, these's perhaps more danger for people who use computers for interest or pleasure in their own homes.
Now, it's obviously not possible to impose in the privacy of people's homes, the sort of safeguards that can be applied in the working environment.
Most people get so fascinated by what they are doing that they stay in front of the screen for hours on end, some are real fanatics.
But they are also using their computers in environments which are not specially designed.
Er, they may be dusty or hot, and not particularly well-lit on the whole.
An English magazine for computer enthusiasts recently ran its own survey.
The readers were invited to send in an account of any health problems they felt were connected with the use of their computers.
Er, interestingly, a long list emerged of complaints both serious and less serious, ranging from constipation because of the long hours spent in sedentary ac, inactivity, and backache due to crouching over an inconveniently positioned keyboard, er, right through to a general sense of fatigue owing to having puzzled over a problem for longer than was sensible.
The visual disturbances mentioned above were also very common.
Some readers who already suffered from short sight found that the condition had worsened, and a rarer complaint, but still one suffered by a significant number, was an itching of the face, which in some cases became a form of dermatitis.
It seems that this is due to the electrostatic field of the video screen attracting dust from the atmosphere, which irritates exposed skin.