ROLE OF HYDROLOGY IN THE IRRIGATION WATER RELATED E. COLI OUTBREAKS ASSOCIATED WITH LEAFY GREEN PRODUCE

In recent years food safety research has focused on developing standard operating procedures for harvesting, packaging, processing and handling fresh produce emphasizing on elimination of microbial contamination at these critical control points. However, the quality of irrigation water, a major factor across the farm to fork continuum, has not been researched as vigorously. Irrigation water has been implicated as a possible source of pathogenic microorganisms on produce linked to major disease outbreaks. Many sources of irrigation water are subject to input of pathogenic loads from point and non-point sources as a result of land uses in the surrounding area of the watershed. We examined two irrigation water related E. coli outbreaks associated with leafy green produce to highlight the role of watershed hydrology and the need for a watershed-based spatio-temporal approach to help understand the underlying causes of foodborne illness outbreaks. We conclude that investigations of fresh produce outbreaks should include analysis of groundwater-surface water interactions, land use practices and run-off processes on a watershed scale.