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The health of people in society is directly related to the health of crops and produce, food animals and the environments in which they are produced. The availability of safe food improves the health of people and is a basic human right. Our food supply and our pet’s food supply are becoming increasingly global and as such our society will be exposed to the food and waterborne pathogens from around the globe. We conduct research through our extension and education programs to identify and, more specifically, prevent future foodborne outbreaks, by focusing on reducing the risk factors leading to contamination of raw agricultural products and reducing the pathogens associated with animal products.

E. coli O157 contamination of lettuce during overhead irrigation

A field trial in Salinas Valley, California, was conducted during July 2011, and again in July and October of 2012 to quantify the microbial load that transfers from wildlife feces onto nearby lettuce during foliar irrigation. Romaine lettuce was grown using standard commercial practices and irrigated using an impact sprinkler design. Five grams of rabbit feces was spiked with 1.29X108 CFU of Escherichia coli O157:H7 and placed 23, 22, and 21 days and immediately before a 2 hr irrigation event. Immediately after irrigation, 168 heads of lettuce ranging from 23 to 69 cm (from 9 to 27 in.) from the fecal deposits were collected, and the concentration of E. coli O157:H7 was determined. Thirty-eight percent of the collected lettuce heads had detectable E. coli O157:H7, ranging from 1 MPN to 2.30X105 MPN per head and a mean concentration of 7.37X103 MPN per head. Based on this weighted arithmetic…

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Potential microbiological risks to produce fields using captured sediment and water

Agricultural recovery basins are an important conservation practice designed to provide temporary storage of sediment and water on farms before low-volume discharge. However, food safety concerns have been raised regarding redistribution of captured sediment and water to fields used for human food production. The purpose of this study was to examine the potential microbiological risk…

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