Escherichia coli Survival on Dry Bulb Onions Treated with Crop Protection Sprays Prepared using Contaminated Water in the Treasure Valley Growing Region

Contaminated agricultural water has been implicated in produce-associated outbreaks, including dry bulb onions (Allium cepa). This study was designed to quantify risks associated with contaminated water used to prepare crop protection sprays applied immediately before the onset of field curing of dr...

Full description

Saved in:
Bibliographic Details
Main Authors: Jason Racine, Alexandra Nerney, Samantha Kilgore, Tim Waters, Faith Critzer, Linda J. Harris, Stuart Reitz, Joy Waite-Cusic
Format: Article
Language:English
Published: Elsevier 2024-12-01
Series:Journal of Food Protection
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S0362028X24001571
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850139235244310528
author Jason Racine
Alexandra Nerney
Samantha Kilgore
Tim Waters
Faith Critzer
Linda J. Harris
Stuart Reitz
Joy Waite-Cusic
author_facet Jason Racine
Alexandra Nerney
Samantha Kilgore
Tim Waters
Faith Critzer
Linda J. Harris
Stuart Reitz
Joy Waite-Cusic
author_sort Jason Racine
collection DOAJ
description Contaminated agricultural water has been implicated in produce-associated outbreaks, including dry bulb onions (Allium cepa). This study was designed to quantify risks associated with contaminated water used to prepare crop protection sprays applied immediately before the onset of field curing of dry bulb onions. Laboratory experiments determining the behavior of Salmonella and Escherichia coli in crop protection chemical solutions were performed to guide selection for field use. Field trials were conducted (2022, 2023) in eastern Oregon (Treasure Valley) using two onion cultivars (‘Red Wing’ and ‘Cometa’) inoculated with a rifampicin-resistant E. coli cocktail (3–4 log CFU/100 mL) suspended in fungicide solution or clay suspension, and applied with a backpack sprayer at the end of the growing season. Onions were sampled through the next 4 weeks of field curing and after 1 and 4–5 mos of postharvest storage. In 2022, onions were initially contaminated at a maximum cell density of 48 MPN/onion (Geometric mean (GM): 3.7 MPN/onion). At the end of curing, a single onion (out of 320) tested positive at 2 MPN/onion. In 2022, E. coli was not detected during postharvest storage (n = 160). In 2023, the application of contaminated sprays resulted in a maximum contamination of 275 MPN/onion (GM: 8.6 MPN/onion). At the end of the 2023 curing period, three out of 320 onions (0.9%) had detectable levels of E. coli (1–2 MPN/onion). Three ‘Cometa’ onions from the same plot that were treated with fungicide were positive for E. coli after 5 months of postharvest storage (2, 11, and 83 MPN/onion). These field trials indicate field curing conditions in the Treasure Valley help mitigate risks associated with contaminated water used for applying crop protection sprays. E. coli was detected on a small percentage of onions at low cell density after curing. The single onion with elevated E. coli populations after postharvest storage had internal damage characteristic of bacterial rot.
format Article
id doaj-art-b10d4755d0544e579212a1f4ebb1afbf
institution OA Journals
issn 0362-028X
language English
publishDate 2024-12-01
publisher Elsevier
record_format Article
series Journal of Food Protection
spelling doaj-art-b10d4755d0544e579212a1f4ebb1afbf2025-08-20T02:30:23ZengElsevierJournal of Food Protection0362-028X2024-12-01871210037310.1016/j.jfp.2024.100373Escherichia coli Survival on Dry Bulb Onions Treated with Crop Protection Sprays Prepared using Contaminated Water in the Treasure Valley Growing RegionJason Racine0Alexandra Nerney1Samantha Kilgore2Tim Waters3Faith Critzer4Linda J. Harris5Stuart Reitz6Joy Waite-Cusic7Department of Food Science and Technology, College of Agricultural Sciences, Oregon State University, Corvallis, OR 97331, USADepartment of Food Science and Technology, College of Agricultural Sciences, Oregon State University, Corvallis, OR 97331, USADepartment of Food Science and Technology, College of Agricultural Sciences, Oregon State University, Corvallis, OR 97331, USAFranklin County Extension, College of Agricultural, Human, and Natural Resource Sciences, Washington State University, Pasco, WA 99301, USADepartment of Food Science and Technology, College of Agricultural and Environmental Sciences, University of Georgia, Athens, GA 30609, USADepartment of Food Science and Technology, College of Agricultural and Environmental Sciences, University of California, Davis, Davis, CA 95618, USAMalheur Experiment Station, College of Agricultural Sciences, Oregon State University, Ontario, OR 97914, USADepartment of Food Science and Technology, College of Agricultural Sciences, Oregon State University, Corvallis, OR 97331, USA; Corresponding author at: Department of Food Science and Technology, Oregon State University, 100 Wiegand Hall, Corvallis, OR 97331, USA.Contaminated agricultural water has been implicated in produce-associated outbreaks, including dry bulb onions (Allium cepa). This study was designed to quantify risks associated with contaminated water used to prepare crop protection sprays applied immediately before the onset of field curing of dry bulb onions. Laboratory experiments determining the behavior of Salmonella and Escherichia coli in crop protection chemical solutions were performed to guide selection for field use. Field trials were conducted (2022, 2023) in eastern Oregon (Treasure Valley) using two onion cultivars (‘Red Wing’ and ‘Cometa’) inoculated with a rifampicin-resistant E. coli cocktail (3–4 log CFU/100 mL) suspended in fungicide solution or clay suspension, and applied with a backpack sprayer at the end of the growing season. Onions were sampled through the next 4 weeks of field curing and after 1 and 4–5 mos of postharvest storage. In 2022, onions were initially contaminated at a maximum cell density of 48 MPN/onion (Geometric mean (GM): 3.7 MPN/onion). At the end of curing, a single onion (out of 320) tested positive at 2 MPN/onion. In 2022, E. coli was not detected during postharvest storage (n = 160). In 2023, the application of contaminated sprays resulted in a maximum contamination of 275 MPN/onion (GM: 8.6 MPN/onion). At the end of the 2023 curing period, three out of 320 onions (0.9%) had detectable levels of E. coli (1–2 MPN/onion). Three ‘Cometa’ onions from the same plot that were treated with fungicide were positive for E. coli after 5 months of postharvest storage (2, 11, and 83 MPN/onion). These field trials indicate field curing conditions in the Treasure Valley help mitigate risks associated with contaminated water used for applying crop protection sprays. E. coli was detected on a small percentage of onions at low cell density after curing. The single onion with elevated E. coli populations after postharvest storage had internal damage characteristic of bacterial rot.http://www.sciencedirect.com/science/article/pii/S0362028X24001571Agricultural WaterField trialFungicidePesticideProduce safetySurrogate
spellingShingle Jason Racine
Alexandra Nerney
Samantha Kilgore
Tim Waters
Faith Critzer
Linda J. Harris
Stuart Reitz
Joy Waite-Cusic
Escherichia coli Survival on Dry Bulb Onions Treated with Crop Protection Sprays Prepared using Contaminated Water in the Treasure Valley Growing Region
Journal of Food Protection
Agricultural Water
Field trial
Fungicide
Pesticide
Produce safety
Surrogate
title Escherichia coli Survival on Dry Bulb Onions Treated with Crop Protection Sprays Prepared using Contaminated Water in the Treasure Valley Growing Region
title_full Escherichia coli Survival on Dry Bulb Onions Treated with Crop Protection Sprays Prepared using Contaminated Water in the Treasure Valley Growing Region
title_fullStr Escherichia coli Survival on Dry Bulb Onions Treated with Crop Protection Sprays Prepared using Contaminated Water in the Treasure Valley Growing Region
title_full_unstemmed Escherichia coli Survival on Dry Bulb Onions Treated with Crop Protection Sprays Prepared using Contaminated Water in the Treasure Valley Growing Region
title_short Escherichia coli Survival on Dry Bulb Onions Treated with Crop Protection Sprays Prepared using Contaminated Water in the Treasure Valley Growing Region
title_sort escherichia coli survival on dry bulb onions treated with crop protection sprays prepared using contaminated water in the treasure valley growing region
topic Agricultural Water
Field trial
Fungicide
Pesticide
Produce safety
Surrogate
url http://www.sciencedirect.com/science/article/pii/S0362028X24001571
work_keys_str_mv AT jasonracine escherichiacolisurvivalondrybulbonionstreatedwithcropprotectionsprayspreparedusingcontaminatedwaterinthetreasurevalleygrowingregion
AT alexandranerney escherichiacolisurvivalondrybulbonionstreatedwithcropprotectionsprayspreparedusingcontaminatedwaterinthetreasurevalleygrowingregion
AT samanthakilgore escherichiacolisurvivalondrybulbonionstreatedwithcropprotectionsprayspreparedusingcontaminatedwaterinthetreasurevalleygrowingregion
AT timwaters escherichiacolisurvivalondrybulbonionstreatedwithcropprotectionsprayspreparedusingcontaminatedwaterinthetreasurevalleygrowingregion
AT faithcritzer escherichiacolisurvivalondrybulbonionstreatedwithcropprotectionsprayspreparedusingcontaminatedwaterinthetreasurevalleygrowingregion
AT lindajharris escherichiacolisurvivalondrybulbonionstreatedwithcropprotectionsprayspreparedusingcontaminatedwaterinthetreasurevalleygrowingregion
AT stuartreitz escherichiacolisurvivalondrybulbonionstreatedwithcropprotectionsprayspreparedusingcontaminatedwaterinthetreasurevalleygrowingregion
AT joywaitecusic escherichiacolisurvivalondrybulbonionstreatedwithcropprotectionsprayspreparedusingcontaminatedwaterinthetreasurevalleygrowingregion