Illustrate three ways by which harmful substances could contaminate food

Pesticides and carcinogens are put on fruits to get rid of harmful insects but are not good for people.

Hair and food: There is a heavy stigma attached to the presence of hair in food in most societies. There is a risk that it may induce choking and vomiting, and also that it may be contaminated by toxic substances. Views differ as to the level of risk it poses to the inadvertent consumer.

Processed foods: Processing contaminants are generated during the processing of foods (heating, fermentation). They are absent in the raw materials, and are formed by chemical reactions between natural and/or added food constituents during processing.

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