Deltathor

Kasi Albert <albert.kasi [at] dpc__sa__gov__au> writes

>We have consulted with a pest control contractor, who has suggested
>the targeted use of Deltathor Insecticide. Deltamethrin is a
>residual pyrethroid (1%), used with propylene glycol (>1%) and
>"other non hazardous ingredients secret (mostly water)" (to 100%).

Did you ever think of a treatment with modified atmospheres like
carbon dioxide? We have been using this successfully even on very
large objects like a complete organ (measures approximately 17 x 8 x
4 meters) and whole historic automobiles.

I would not recommend the use of chemical fumigants on such a
"complex" object, because the danger of reactions especially with
textile and leather dyes and/or plastic surfaces is not predictable.
It is also most likely (as for example experience told about the
organ, which had been treated with some 3 or 4 "waves" of different
insecticides before) that a chemical treatment will not get the
complete infestation.  Even with very aggressive chemicals (that
also promised a prolonged "depot effect" and are off the market
today because of their extreme toxicity) directly sprayed on, enough
of the little beasts survived to continue.  The only effect they got
in case of the organ was an accumulation of different
unhealthy/poisonous substances in the object.  This now continuously
contaminates the atmosphere in the museum and creates critical
conditions for the museum employees, who have to work in the
exhibition the whole day.

There is an book review on the subject of modified atmospheres as
conservational treatment on Cool

    <URL:http://cool.conservation-us.org/jaic/articles/jaic39-03-006_indx.html>

    Charles Selwitz and Shin Maekawa.
    Inert Gases in the Control of Museum Insect Pests.
    Los Angeles: Getty Conservation Institute, 1998.
    107 pages, softcover, $25.

Available from

    Getty Trust Distribution Center
    Dept. C142
    PO Box 49659
    Los Angeles, California 90049-0659
    ISBN 0-89236-502-1.

In case of a treatment with modified atmospheres it will of course
be important to check, if there are other infested objects in the
exhibition.  They will have to be treated too or must be separated
from the carriage to avoid an immediate re-infestation.

Gundula Tutt
Diplomrestauratorin
Kaiserstuhlstrasse 24
79279 Vorstetten
+49 7666 8801829
Mobile: +49 177 3495192


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                  Conservation DistList Instance 26:35
                 Distributed: Tuesday, January 29, 2013
                       Message Id: cdl-26-35-005
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