What is the Root Cause of This One?

Serious Incident:
*28 injuries (illness)
*7 sent to the hospital
*Building Evacuated
*911 Called
*Hazmat team called in

Here is the story:

http://news.yahoo.com/s/ap/odd_rotten_office_food

Does your office have a “fridge cleaning business plan?”  Audits, evaluations?  If not, better get on it!