Zip lock bags and wet collections

This inquiry is from one of my colleagues at the Canadian Museum of
Nature.

    Has anyone had experience using zip-lock type baggies in wet
    collections?  We are proposing to use individual polyethylene
    baggies to hold and separate different specimens inside a large jar.
    The fluid preservative should be a uniform 70% ethanol, both inside
    the baggies and in the large jar.  In use like this, has anyone
    noticed breakdown, embrittlement of the baggie, or  unusual
    differences in alcohol concentration, or any other conditions?

    **** Moderator's comments:   For some background, see Doug
    Nishimura's post in Conservation DistList Instance: 4:57, May 4,
    1991

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                  Conservation DistList Instance 11:32
                  Distributed: Monday, October 6, 1997
                       Message Id: cdl-11-32-014
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