Mold on paintings

Dennis Baltuskonis <dbaltusk [at] trinity__edu> writes

>I am researching the topic of mold damage to artwork, in particular
>oil on canvas paintings. ...

>I am researching the topic of mold damage to artwork, in particular
>oil on canvas paintings. ...
>...
>Recently the courts in Texas have declared that the presence of mold
>in homes is not a health threat (at least like it used to be
>considered). This begs the question then if a home, filled with
>artwork, experiences a severe outbreak of mold what are the dangers
>of this situation and what is the recommended solution to the
>problem? ...

I work as a paper and preventive conservator and have, on the odd
occasion, been asked to examine water, sewage or mould damaged works
in people's homes or offices.

To the best of my knowledge, the chance of an allergic reaction
developing on the part of the owner is dependent on the
concentration of mould spores (the higher the concentration, the
more likely you are to see a reaction) and the length of the
exposure, so if you live in a mouldy house for a long time, you are
more likely to develop chronic health problems.

Often in insurance claims severely damaged items are discarded and
replaced. For example, this is standard with soft furnishings
damaged by sewage. The issue for art works is therefore that they
cannot be discarded and replaced, and furthermore that it is not
always possible to remove all of the mould (or contaminant) from the
surface and substrate of the work. The risk to the owner then
depends on the level of contamination present. I think in general
the level of residual contamination in the house and furnishings
will have much more of an impact than the residual contamination on
one or two art works.

The degree of risk is always difficult to determine, though, because
any one person has their own degree of sensitivity - one person may
experience a reaction, where another will not. I worked on one
project where business archives had been sitting in a mouldy
building for years - there was no visible mould growth, but a very
high spore count in the air and on surfaces. One staff member who
had worked in the building for 10 years broke out into a rash
whenever she handled the documents and couldn't even bear the smell.
Everyone else was fine--this particular person had become
sensitised. The real issue was the building, but the documents were
sufficiently contaminated to provoke a response.

This person may never be able to handle the documents ever again
even if they were clean, because of a physio-psychological reaction
(not sure if that is the correct term), which sounds dodgy but is a
very real reaction, e.g. people who have had smoke-damaged
mattresses "cleaned" rather than than replaced (because of their
insurance agreement) will still smell smoke when no one else
can--and therefore the insurance agreement will never be happily
settled. (This may be something to keep in mind--insurance agents
don't like unsettled claims; they seem to like them to go away).

I have always recommended, though, thorough cleaning of works
damaged in these cases, as far as is possible, because in my view it
is best for art work and owner alike to be exposed to as few mould
spores as possible in the long term. In some cases we have looked at
having surface swabs taken to do spore counts etc, to determine the
effectiveness of treatment and the level of residual contamination
(done through a testing authority/analytical lab), especially for
cases like the previous example, where the mould was not visible.
Then you run into problems when trying to figure out what is an
acceptable level, because every sample will have *some* mould spores
present.

The trouble is, we judge risk differently to insurance agencies, and
we tend to be on the more cautious side. Whether or not cleaning
went ahead in these cases depended on whether the insurance agent
thought the expense was warranted, according to the risk, and this
assessment will vary from insurance agent to insurance agent and
from state to state, country to country etc depending on legislation
and the particulars of the insurance agreement. Clearly in Texas the
current thinking is that residual mould on art works is not a health
risk! It is a very difficult thing to "prove", because people's
reactions are so variable, and because reactions to residual mould
may take some time to appear, as it is living alongside mould for
years that often causes the worst problems.

Proximity may also be an issue. For example, if someone has their
desk or bed underneath a slightly mouldy work, they may be more
likely to develop a reaction, as opposed to a slightly mouldy work
handing in the hallway. Obviously, interactions between people and
things are much harder to predict and control in homes and
businesses than they are in museums and galleries. I hope this
helps--I think I might have got off the track of your question.

Alice Cannon
Paper Conservator
The Centre for Cultural Materials Conservation
University of Melbourne


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                  Conservation DistList Instance 19:7
                  Distributed: Thursday, July 21, 2005
                        Message Id: cdl-19-7-006
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