Iceberg lettuce served at the Peel Memorial Hospital in Brampton, Ontario, Canada, between October 30 and November 1, was the implicated vehicle in an outbreak of E. coli O157:H7. The lettuce was a single box of imported iceberg lettuce. The kitchen staff had filed an incident report upon receipt of the lettuce because of heavy soilage, but it was used anyway. The kitchen food preparation and storage practices appeared good. Available food samples were tested, but showed no evidence of contamination, however no samples of food served between October 30 or November 1 were available for testing.