Which of the following represents a biological hazard in food safety?

Bacteria represent a biological hazard in food safety because they are living microorganisms that can cause illness in humans when consumed in contaminated food. Biological hazards encompass a wide range of pathogens, including bacteria, viruses, parasites, and fungi, that can proliferate in food products if not managed properly. These hazards can lead to foodborne illnesses, which pose significant health risks to consumers.

For instance, specific bacteria such as Salmonella, E. coli, and Listeria are particularly notorious for causing food poisoning outbreaks. This emphasizes the need for stringent controls and monitoring throughout the food supply chain to prevent contamination, ensuring that food is safe for consumption.

The other options, while important in the context of food safety, do not represent biological hazards. Pesticides are considered chemical hazards, as they are substances used to kill pests and may leave residues on food. Heavy metals, such as lead or mercury, are also categorized as chemical hazards, stemming from environmental contamination and industrial processes. Food additives, which are substances added to food to preserve flavor or enhance taste and appearance, are not biological in nature either, but rather they fall under the category of additives and may raise concerns if misused or present in excessive amounts.