Raw foods of animal origin are the most likely to be contaminated; that is, raw meat and poultry, raw eggs, unpasteurized milk, and raw shellfish. Foods that mingle with the products of many individual animals, such as bulk raw milk, pooled raw eggs, or ground beef, are hazardous because a pathogen present in any one of these animals may contaminate the whole batch. Fruits and vegetables consumed raw are a particular concern. Washing can decrease but not eliminate contamination. Using water that’s not clean can contaminate many boxes of produce.
Fresh manure used to fertilize vegetables can also contaminate them. Unpasteurized fruit juice can also be contaminated if there are germs in or on the fruit that’s used to make it.