Over the past decade incidents of foodborne illness resulting from contaminated produce, most notably baby spinach and iceberg lettuce, by E. Coli O157:H7 and Salmonella have escalated sharply.
Dr. Rick Holley, with the University of Manitoba's Faculty of Agricultural and Food Sciences, says, while the cause is not certain, the evidence suggests irrigation water and improperly composted livestock manure are possible sources.
He explains, pathogens carried in feed ingredients end up being recycled through the animal in manure which is then used, as it should, to fertilize crops.
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