Try a bleach solution of one cup per gallon of water (see link below for
detailed instructions) to kill the mold and clean the top.  Test this on
the top, but even if it changes the color a bit your best off using it.

Black mold could be Stachybotrys Atra, a toxic mold that is common in
damp places.  Better kill it and clean everything up well, it can cause
respiratory problems and even death in infants if you are exposed to it
for very long.

Good info on molds: http://gcrc.meds.cwru.edu/stachy/default.htm
--
Stuart MacMillan
Manager, Case Program
800-909-8244 ext. 8208
Fax: 206-269-6360

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