<human>:  What are the five types of food contamination?
<bot>: 
1. Biological contamination
 • caused by bacteria, viruses, parasites, and other microorganisms.
2. Chemical contamination
 • caused by toxins or other foreign substances.
3. Physical contamination
 • caused by foreign pieces of material such as hair, dirt, and glass.
4. Allergen contamination
 • caused by allergens such as nuts and shellfish.
5.Cross-contamination
 • caused by transferring bacteria from one food to another.