A careless employee leaves a hose in a bucket of dirty mop water. What type of contamination occurs?

The scenario describes a improper situation where a hose is left in a bucket of dirty mop water, which can lead to the introduction of contaminants into the drinking water supply. This situation exemplifies back siphonage, a form of contamination that occurs when a negative pressure in the water supply system causes water to flow backward, pulling contaminants from the mop water into the clean water lines.

Understanding that back siphonage results from a direct physical connection between a clean water source and a contaminated source is crucial. In this case, the hose acts as a link between the dirty mop water and the clean water supply. The potential for contaminants spreading to areas where food and clean water are present makes it a serious concern for food safety and public health.

Other types of contamination mentioned in the options, such as surface contamination, typically relate to contaminants settling on surfaces that might directly touch food. Foodborne illness is the result of consuming contaminated food or beverages, while cross-connection refers more broadly to any unprotected physical connection between a potable water supply and a non-potable one. Understanding these distinctions is essential in maintaining safe food handling practices.