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ARS Home » Northeast Area » Beltsville, Maryland (BARC) » Beltsville Agricultural Research Center » Environmental Microbial & Food Safety Laboratory » Research » Publications at this Location » Publication #337545

Research Project: Characterization and Mitigation of Bacterial Pathogens in the Fresh Produce Production and Processing Continuum

Location: Environmental Microbial & Food Safety Laboratory

Title: Generic E. coli levels in surface and nontraditional irrigation water in the mid Atlantic in relation to FSMA water quality standards: A CONSERVE study

item ALLARD, SARAH - University Of Maryland
item SOLAIMAN, SULTANA - University Of Maryland
item CALLAHAN, MARY - University Of Maryland
item MAY, ERIC - University Of Maryland Eastern Shore (UMES)
item HASHEM, FAWZY - University Of Maryland Eastern Shore (UMES)
item PARVEEN, SALINA - University Of Maryland Eastern Shore (UMES)
item KNIEL, KALMIA - University Of Delaware
item Sharma, Manan
item Handy, Eric
item East, Cheryl - Roberts
item MICALLEF, SHIRLEY - University Of Maryland
item SAPKOTA, AMY - University Of Maryland

Submitted to: International Association for Food Protection
Publication Type: Abstract Only
Publication Acceptance Date: 3/17/2017
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Introduction: The use of surface (pond and river) and nontraditional (reclaimed wastewater, produce wash water) irrigation water (SNIW) could reduce stress on ground water resources. However, it is essential to understand how these irrigation sources may influence the microbiological safety of fresh produce, and how they comply with FSMA irrigation water quality standards (Geometric Mean (GM) of 126 CFU/100ml and Statistical Threshold Value (STV) of 410 CFU/100ml of Escherichia coli). Purpose: To evaluate SNIW sources for the presence of generic E. coli and compare the GM and STV from these sites to FSMA standards. Methods: Surface and nontraditional irrigation water (100ml) from 12 sites (n=51) in the Mid-Atlantic was collected and filtered for enumeration of E. coli by standard membrane filtration (EPA Method 1604). Water from 8 surface water sites, 3 reclaimed waste water sites, and a produce processing facility were evaluated on up to 6 different dates (Sept–Dec 2016). E. coli was quantified on MI agar, and GM and STV were calculated from all available data. Results: E. coli levels below 126 CFU/100ml were found in 47% of water samples analyzed. Of the 12 sites analyzed, 7 had a GM above the 126 CFU/100ml FSMA threshold. The FSMASTV of 410 CFU E. coli/100ml was exceeded in 10/12 sites examined. Of all surface and nontraditional water sources tested, only 2 sites, both reclaimed wastewater, had E. coli levels below GM and STV thresholds. Overall, samples collected from river water and vegetable processing sites contained higher levels of E. coli, while reclaimed wastewater (chlorinated before sampling) and pond water contained lower levels of E. coli.. Significance: Many surface and nontraditional irrigation water sources in the Mid-Atlantic analyzed from Sept–Dec 2016 would require mitigation before use as irrigation waterforfresh produce crops to comply with FSMA standards.