naomi (03/15/83)
#N:ubc-medgen:5500001:000:2614
ubc-medgen!naomi Mar 15 10:32:00 1983
I know we've been through this before, but I'd like to keep the discussion
of VDT safety going.
As you may have heard, there was an outbreak of miscarriages among VDT
operators in Surrey Memorial Hospital, near Vancouver. Needless to say, our
secretarial staff feel nervous about the safety of our terminals (which
apparently do not have PCBs.) This is the second such outbreak I know of
in Canada, but I still have not seen the results of the investigations of
these incidents.
I have heard over and over that the main work hazards are eye-strain, etc.
However, I don't believe that these were follow-ups of miscarriage cases.
Has anyone out there heard any results from any follow-up studies?
Another thing that is puzzling, is that there are a lot of female programmers
and I haven't heard too many reports of pregnancy problems among them. Of
course, there are a lot more women who use word-processors, or data entry
equipment. Does anyone know of any reports that
suggest an abnormal incidence of miscarriages among women programmers?
Statistics on miscarriage rates are surprisingly hard to come by.
Miscarriage in the first few weeks is often unreported and possibly not
known even to the mother. I work in a department that uses this type of
information, but the best we could find was 10-40% spontaneous abortion in
the first 20 weeks (after that it is a "stillbirth".) The stillbirths add
another 5-10%. Women over 30 are at the high end of this scale.
In short, a very high percentage of pregnancies do not come
to term. So, in a group of 5-10 pregnant women, there is a quite high
probability of 3 or more miscarriages, without appealing to common causes -
even psychosomatic ones. By comparison, breast cancer is much rarer than
miscarriage, but I was told of a work situation in which 5 of 12 women were
diagnosed with breast cancer in a 6 month period.
Statistics is a wonderful field. When I started this article, yesterday, I
made a list of all the women I know who have been pregnant and came up
with a somewhat higher miscarriage rate for the VDT users. However, most of
these women were in their 30s, compared to the nonusers, who were in their
20s. Now that I see the statistics, fuzzy though they are, I feel very
reassured, and have come to believe that these "outbreaks" of miscarriages
can be explained as statistical phenomenon. (Randomness implies clustering!)
not afraid to be a biostatistician and use a VDT
but a bit scared of being over thirty
Naomi Altman
!decvax!microsoft!uw-beaver!ubc-vision!ubc-medgen!naomiminow (03/17/83)
All of the studies I've read -- including several in Swedish -- concluded that VDT's did not generate any "dangerous radiation" (either ultra-violet or X-ray). (Studies were done by the Swedish Work Safety Board and published in OEstberg, O, "Display terminals aren't dangerous" Arbetsmiljoe 1, 1976. (In Swedish) There are other possible problems, however. One, noted by Norwegian researchers, is that static electricity buildup may cause airborne dust particles to settle on workers' skin, possibly causing excema. Stress is probably the most likely cause of "terminal-related" sicknesses. One reason programmers are less likely to have problems is that they have more control of their work: a data-entry operator often has production goals (so and so many thousand keystrokes per hour) and may not have any social contact during work periods. It goes without saying that stress is not good for pregnant women (or anybody else, for that matter). Martin Minow decvax!minow