| Shared food preparation (blender, pan, fryer, grill, etc) |
| Cross contact of primary food with allergen (eg, vanilla ice cream previously contacted with peanut ice cream from prior scoop, vegetable tray containing walnut from a prior spill) |
| Poor communication between consumer and chef |
| Hidden or "secret ingredients" (allergen in sauces, powder forms) |
| Cross contact during serving (buffet, preparation trays, garnish, spills) |
| Addition of allergen after final preparation (added butter, etc) |
| Removal of ingredient with residual allergen (removing nuts from a salad) |
| Foods prepared in advance and ingredients unknown |
| Allergen used without notion of "ingredient" (peanut butter to seal an egg roll, nuts for decoration) |
