Which of the following items is considered a physical hazard in food?

Toothpicks are classified as a physical hazard in food because they can accidentally break off and contaminate food, posing a choking risk or causing injury to those who consume the contaminated food. Physical hazards include any foreign objects that can be ingested and can compromise the safety of the food supply.

On the other hand, hair dye is not a physical hazard but a chemical one, as it consists of substances that can cause harm if ingested. Preservatives are also chemical additives that serve a specific purpose in food preservation, rather than being physical objects that may cause harm. Cooking oil, while it is a food item, does not present a physical risk in terms of choking or injury, as it does not consist of solid foreign objects.