Gamma radiation

Patrick Sinco <psinco [at] ans__org> writes

>I am a reporter researching an article on the use of gamma radiation
>to preserve damaged paper documents. I understand that the procedure
>is not widely used in the field of preservation, but would like to
>learn when and how it is used and how well it performs its task....

Gamma irradiation has been used in the industry for some time as a
method as sterilization, in Great Britain, substances as divers as
spices hospital equipment and cosmetics are routinely sterilized by
irradiation with gamma rays. In the USA this technique has recently
been extended to include items of food such meat and vegetables .

Gamma rays which are form of electromagnetic radiation would make an
excellent biocide in many respects, it leaves no hazardous residues
(chemical or radioactive) complete penetration of the object can be
achieved unlike the action of surface fungicides (such as thymol)
large objects can be easily treated as small ones. Recent studies
have for instance been undertaken in Czechoslovakia, Romania and
America, preliminary results indicated that this might prove a
possible technique for mass disinfection of archives, especially if
the synergistic effect of radiation and heat as utilized. But as yet
the long-term effect on the physic chemical properties of the paper
need to be established, as not only does the initial damage occur
with higher degrees but also reactions may only be seen to occur of
the further treatments. Research indicated that radiation doses of
up to 10 kilo Grays (kGy) had little or no perceptible effect on the
properties of paper.(1,2,3,4,5)

Reference

    1. Toufexis, A.
    Food fight over gamma rays.
    Time Magazine Sept. 1986.

    2. Harakova, H. and Martinek, F.
    Disinfection of archives documents by ionization radiation.
    Restaurator vol.6, pp. 205-216,1984.

    3. Beck, W.
    L`emloi des raditions ionisantes pour l`anninissemenet du bois
    ancien.
    In ICOMOS symposium on the Weathering of Wood, Ludwigsburg,
    Germany (June 1969) pp. 51-68.

    4. Pavoun Flores, S.C.
    Gamma radiation as fungicide and its effects on paper.
    Bulletin of American Institute for Conservation vol. 16 (1975)
    pp. 15-44.

    5.  Bonety, Gallo.F., and others.
    Essais sur l`utilisation des rayons pour starilisation des
    materiaux libraires.
    Studies in Conservation, vol. 24 (1979) pp. 59-68.

Michael Maggen,
Head of Paper Conservation Dept.
The Israel Museum Jerusalem,
POB 71117, Jerusalem 91710, Israel.
+972 2 67 08 808
+972 2 6711894 (h)
Fax: +972 2 56 31 833


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                  Conservation DistList Instance 13:46
                  Distributed: Tuesday, March 7, 2000
                       Message Id: cdl-13-46-008
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