Consumers naturally expect that food they eat will not make them sick. Bacteria that cause illness, such as E. coli and Salmonella, can be present in manures added to soil or carried in irrigation water. It is critically important to prevent these human pathogens contaminating leafy vegetables.

In this study, a survey showed that human pathogens were rarely found on Australian fresh vegetables. Pathogenic bacteria were found on less than 1% of 5,533 samples, with most at levels unlikely to cause illness. Bacteria were also uncommon in samples of manure/compost used on farms and in irrigation water.