Freeze-drying

David A. Tremain <david_tremain [at] pch__gc__ca> writes

>I feel it is important to clarify the point I made about mold in my
>last posting about freeze-drying (Conservation DistList Instance:
>16:59 Monday, April 7, 2003).

Regarding the issue of freeze-drying moldy materials, in addition to
David's point relating to the risk that the spores may be
reactivated, is the concern that even dormant or dead mold spores
may cause allergenic reactions.  This means that those people who
are handling these materials, either for processing or research, may
develop the same kinds of allergic reactions that we allergy
sufferers have on a day in spring or fall: runny nose, scratchy
throat, watery eyes. Nevertheless, we do not usually walk about
rubbing our noses into Goldenrod or Pecan pollen, but while reading,
we may unconsciously rub our eyes, or touch our nose or mouth,
aggravating the reaction. While some institutions may allow
researchers to handle material that has been treated in a way that
kills the spores or puts them into dormancy, others have removed
such materials from circulation, and may choose to HEPA vacuum the
spores to remove  them physically, before serving them.  If the
institution chooses not to do this, researchers should at least be
warned not to touch their faces while working, and to wash their
hands thoroughly afterwards.

There is a very wide range of opinion among conservators and among
occupational hygienists regarding the risks presented to the public
by mold, or lack thereof. What is certainly accepted practice is
that once mold infiltrates your building structure, the structural
elements need to be removed.  When this involves sheetrock, the
treatment can look like asbestos abatement.  Whatever is decided in
this instance, the institution needs to look at the systemic cause
of the moisture, and take the steps needed to eliminate it, or they
will be faced with these same questions in the future.


                                  ***
                  Conservation DistList Instance 16:61
                 Distributed: Wednesday, April 16, 2003
                       Message Id: cdl-16-61-008
                                  ***