VDT Radiation Danger
  Summ: D. Lauffer

        The New Yorker recently ran a series of articles under the
   heading of "The Annals of Radiation" by Paul Brodeur.  They
   covered research and the industry responses to possible dangers
   from a variety of radiation sources.  The articles covered power
   lines, microwave sources and Video Display Terminals.  Brodeur
   relies heavily on the work of several epidemiologists,
   microbiologists and the maverick, Louis Slesin, editor of the
   Microwave News and the VDT News.  The VDT article appeared in the
   6-26-89 issue of the New Yorker (an issue with skateboarders on
   the cover if you are looking in the local library). Since I do
   not have training in either medicine or electrical engineering, I
   am only offering a very brief, uncritical summary of the VDT
   article.

        Brodeur points out that the groups most likely to fund
   research into radiation dangers are the military and computer and
   electronics manufacturers. All of these have a vested interest in
   downplaying health hazards associated with regular use of VDTs
   both by the public and by their own personnel.  The medium most
   likely to spread detailled information about hazards would be the
   newspapers, who have reporters, editors and clerks who take
   classified ads all of whom might hold them responsible for health
   risks.  The Columbia Journalism Review has documented the lack of
   coverage by the press in articles in 1981 and 1984. Additionally,
   there is documentation that NIOSH and the FDA have been lax in
   pursuing problems in this area, even though they had announced
   studies of the problem.

        The major hazards no longer involve the X-Rays which had
   been emitted by the CRTs and consumer TVs in the past. They seem
   to lie in the magnetic radiation emitted by transformers
   associated with the changing image on the VDT. Epidemiologists
   have noted high incidence of miscarriages among VDT operators.
   This seems to correspond to research on Extra Low Frequency
   radiation (ELF) and Very Low Frequency radiation (VLF) which are
   emitted by components such as the fly-back transformer in the
   VDT.  These components are often near the outside of the device,
   and are even more likely to send radiation to the sides or to the
   back of the terminal.

        Embroylogy research on chickens by Delgado, who has taught
   at Yale, indicated that serious changes were caused in early
   development by 100Hz magnetic radiation. The results were
   confirmed in a Swedish study, which led to banning VDTs which are
   not shielded for VLF in Sweden as of 1988.  IBM now markets a VDT
   (only available in Scandinavian Countries) which meets VLF
   guidelines. Other research has found that as little as 15 minutes
   of exposure to ELF accelerates DNA/RNA transfer in insects. This
   would indicate a potential for problems in fetal development for
   early stage pregnant women who work at VDTs.

        An additional area of problems is the role of magnetic
   fields in these ranges in the increased incidence of childhood
   cancer.  These are usually associated with power lines near
   residences.  Epidemiologists have also noted increased incidence
   of cancer in adult VDT operators.

   Recommendations

        When VLF-shielded terminals become available, these should be
        given strong consideration for new purchases and
        replacements.

        When ELF-shielded terminals become available, these should be
        also given strong consideration for new purchases and
        replacements. These will require transformer shielding in Mu-
        metal.

        This is not a problem with liquid crystal displays LCD, such
        as are found in Laptop Computers.

        With the present generation of equipment you should sit 28
        inches in front, and about 40 inches away from any other
        terminal.

   Waiver of responsibilty

        I am still not sure that I understand all this material, and
   I am in no position to critique the positions taken.  However,
   I'd rather be aware of the possibilities and and be conservative
   in my approach to my own safety.  If this is like other lengthy
   articles in the New Yorker, it should be published in book form
   shortly.  It will be very interesting to see what sort of
   reception the wider dissemination of these ideas gets, both from
   the industry and the press.



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