All Cultures in Refrigerator Appear to Die - (Feb/05/2013 )

Before the lab took a break for Christmas, streak plates stored in our refrigerator would typically remain viable for about two months. Post-break, the same cells on the same media seem to last anywhere from a few days to a week. We suspect that some unnoticed contaminant has afflicted the ice box. The plates don't show mold growth or plaques, so we are unsure of what it might be. One possibility is that around the start of the Christmas break, one lab member began storing uncured PDMS in the refrigerator. Could that be the cause? Has anyone else experienced this, and solved the problem? Thank you for sharing your experiences with me.

could be antibiotic degradation?

or Ice box temperature??