Mold on photographic negatives

For a professional photographer friend:

Does anyone have any suggestions for preventing the spread of mould
growth on photo. neg. emulsion.  What measures might be taken to
safely clean off mould spots on 1940's b&w still film negs?
Obviously, part of the image is probably already lost.  Any advice
welcome.  Thanks,

John Sanford
Dunbar Library Special Collections
Wright State University
Dayton, OH 45435-937-775.2092  fax:775.4109

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                  Conservation DistList Instance 11:42
                Distributed: Wednesday, November 5, 1997
                       Message Id: cdl-11-42-013
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