Mold

I would like to reply to two queries of mold treatment/removal
posted by Mark G. Vine and Zu-Chun Liao. I am assuming that Mark
Vine tested fungi and assessed that they are active. If this is the
case, he needs to take precautions when undertaking the treatment
and wear gloves and respirators to prevent development of fungi
related infections called mycosis. They are difficult to treat. The
same advice would apply to Zu-Chun Liao. One general comment. Fungi
are usually active in higher humidity, above 70%. In dry environment
they will create dormant forms, ready to grow in more favorable
conditions (when humidity is higher and temperature right). The
dormant forms however after some time loose their power to be
activated. I am vague as to the time, because it varies for each
fungus, some may remain active for weeks and others for years.

The safest way to remove fungi residue, either spores or mycelium,
according to  my experience, is to use mechanical methods, such as
vacuum micro-tweezers and/or scalpels. My experiments with laser
used for removal of fungi concentrated on art works on paper. I am
not aware of any conservator who experimented with laser cleaning of
fungi on oil paintings.

When you say that fungi are "embedded" do you understand that their
reproductive mycelium is embedded, or just that they are growing
through the substrate of your painting?. In the first case, when
fruiting body is embedded, you need to extract each one
mechanically, under a higher magnification. In the second case, a
removal with vacuum tweezers should be sufficient.

The same advice applies to both cases, even though the paintings
structure differs so much from manuscripts. Fungi will act similarly
on both supports, because their structure is the same, regardless of
the type of support. A particular care needs to be exercised when
removing fungi from manuscript pages, to prevent from smudging
colored fruiting bodies. Pigmentation produced by spores is
difficult to remove.

I would like to refer both authors to some of my papers which were
published on the above subject in The Paper Conservator, 10th
Anniversary Conference of IIC, 1986 (Biodeterioration of Art Objects
on Paper), AIC Journal 1989 (A study of the removal and prevention
of fungal stains on paper), CAN 1989, leaflet, Assessing the
activity of fungal growth on art objects with a view to possible
fumigation.

If the authors would like to ask me more specific questions, I will
be glad to respond directly.

Hanna Szczepanowska
Preservation Officer/Head Conservator
Conservation Department
MD State Archives
350 Rowe Blv.
Annapolis MD 21401
410-974-3914

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                  Conservation DistList Instance 11:95
                   Distributed: Friday, May 22, 1998
                       Message Id: cdl-11-95-003
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