Escherichia coli transfer from simulated wildlife feces to lettuce during foliar irrigation: A field study in the Northeastern United States

Daniel L. Weller, Jasna Kovac, David J. Kent, Sherry Roof, Jeffrey I. Tokman, Erika Mudrak, Barbara Kowalcyk, David Oryang, Anna Aceituno, Martin Wiedmann

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

Wildlife intrusion has been associated with pathogen contamination of produce. However, few studies have examined pathogen transfer from wildlife feces to pre-harvest produce. This study was performed to calculate transfer coefficients for Escherichia coli from simulated wildlife feces to field-grown lettuce during irrigation. Rabbit feces inoculated with a 3-strain cocktail of non-pathogenic E. coli were placed in a lettuce field 2.5–72 h before irrigation. Following irrigation, the E. coli concentration on the lettuce was determined. After exclusion of an outlier with high E. coli levels (Most Probable Number = 5.94*108), the average percent of E. coli in the feces that transferred to intact lettuce heads was 0.0267% (Standard Error [SE] = 0.0172). Log-linear regression showed that significantly more E. coli transferred to outer leaves compared to inner leaves (Effect = 1.3; 95% Confidence Interval = 0.4, 2.1). Additionally, the percent of E. coli that transferred from the feces to the lettuce decreased significantly with time after fecal placement, and as the distance between the lettuce and the feces, and the lettuce and the sprinklers increased. These findings provide key data that may be used in future quantitative risk assessments to identify potential intervention strategies for reducing food safety risks associated with fresh produce.

Original languageEnglish (US)
Pages (from-to)24-33
Number of pages10
JournalFood Microbiology
Volume68
DOIs
StatePublished - Dec 1 2017

Fingerprint

Lettuce
New England
Northeastern United States
Feces
lettuce
wildlife
feces
irrigation
Escherichia coli
head lettuce
quantitative risk assessment
fresh produce
avirulent strains
Food Safety
pathogens
sprinklers
food safety
leaves
confidence interval
Linear Models

All Science Journal Classification (ASJC) codes

  • Food Science
  • Microbiology

Cite this

Weller, Daniel L. ; Kovac, Jasna ; Kent, David J. ; Roof, Sherry ; Tokman, Jeffrey I. ; Mudrak, Erika ; Kowalcyk, Barbara ; Oryang, David ; Aceituno, Anna ; Wiedmann, Martin. / Escherichia coli transfer from simulated wildlife feces to lettuce during foliar irrigation : A field study in the Northeastern United States. In: Food Microbiology. 2017 ; Vol. 68. pp. 24-33.
@article{f81253c5cf3e48169d149b92310dc7f4,
title = "Escherichia coli transfer from simulated wildlife feces to lettuce during foliar irrigation: A field study in the Northeastern United States",
abstract = "Wildlife intrusion has been associated with pathogen contamination of produce. However, few studies have examined pathogen transfer from wildlife feces to pre-harvest produce. This study was performed to calculate transfer coefficients for Escherichia coli from simulated wildlife feces to field-grown lettuce during irrigation. Rabbit feces inoculated with a 3-strain cocktail of non-pathogenic E. coli were placed in a lettuce field 2.5–72 h before irrigation. Following irrigation, the E. coli concentration on the lettuce was determined. After exclusion of an outlier with high E. coli levels (Most Probable Number = 5.94*108), the average percent of E. coli in the feces that transferred to intact lettuce heads was 0.0267{\%} (Standard Error [SE] = 0.0172). Log-linear regression showed that significantly more E. coli transferred to outer leaves compared to inner leaves (Effect = 1.3; 95{\%} Confidence Interval = 0.4, 2.1). Additionally, the percent of E. coli that transferred from the feces to the lettuce decreased significantly with time after fecal placement, and as the distance between the lettuce and the feces, and the lettuce and the sprinklers increased. These findings provide key data that may be used in future quantitative risk assessments to identify potential intervention strategies for reducing food safety risks associated with fresh produce.",
author = "Weller, {Daniel L.} and Jasna Kovac and Kent, {David J.} and Sherry Roof and Tokman, {Jeffrey I.} and Erika Mudrak and Barbara Kowalcyk and David Oryang and Anna Aceituno and Martin Wiedmann",
year = "2017",
month = "12",
day = "1",
doi = "10.1016/j.fm.2017.06.009",
language = "English (US)",
volume = "68",
pages = "24--33",
journal = "Food Microbiology",
issn = "0740-0020",
publisher = "Academic Press Inc.",

}

Escherichia coli transfer from simulated wildlife feces to lettuce during foliar irrigation : A field study in the Northeastern United States. / Weller, Daniel L.; Kovac, Jasna; Kent, David J.; Roof, Sherry; Tokman, Jeffrey I.; Mudrak, Erika; Kowalcyk, Barbara; Oryang, David; Aceituno, Anna; Wiedmann, Martin.

In: Food Microbiology, Vol. 68, 01.12.2017, p. 24-33.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Escherichia coli transfer from simulated wildlife feces to lettuce during foliar irrigation

T2 - A field study in the Northeastern United States

AU - Weller, Daniel L.

AU - Kovac, Jasna

AU - Kent, David J.

AU - Roof, Sherry

AU - Tokman, Jeffrey I.

AU - Mudrak, Erika

AU - Kowalcyk, Barbara

AU - Oryang, David

AU - Aceituno, Anna

AU - Wiedmann, Martin

PY - 2017/12/1

Y1 - 2017/12/1

N2 - Wildlife intrusion has been associated with pathogen contamination of produce. However, few studies have examined pathogen transfer from wildlife feces to pre-harvest produce. This study was performed to calculate transfer coefficients for Escherichia coli from simulated wildlife feces to field-grown lettuce during irrigation. Rabbit feces inoculated with a 3-strain cocktail of non-pathogenic E. coli were placed in a lettuce field 2.5–72 h before irrigation. Following irrigation, the E. coli concentration on the lettuce was determined. After exclusion of an outlier with high E. coli levels (Most Probable Number = 5.94*108), the average percent of E. coli in the feces that transferred to intact lettuce heads was 0.0267% (Standard Error [SE] = 0.0172). Log-linear regression showed that significantly more E. coli transferred to outer leaves compared to inner leaves (Effect = 1.3; 95% Confidence Interval = 0.4, 2.1). Additionally, the percent of E. coli that transferred from the feces to the lettuce decreased significantly with time after fecal placement, and as the distance between the lettuce and the feces, and the lettuce and the sprinklers increased. These findings provide key data that may be used in future quantitative risk assessments to identify potential intervention strategies for reducing food safety risks associated with fresh produce.

AB - Wildlife intrusion has been associated with pathogen contamination of produce. However, few studies have examined pathogen transfer from wildlife feces to pre-harvest produce. This study was performed to calculate transfer coefficients for Escherichia coli from simulated wildlife feces to field-grown lettuce during irrigation. Rabbit feces inoculated with a 3-strain cocktail of non-pathogenic E. coli were placed in a lettuce field 2.5–72 h before irrigation. Following irrigation, the E. coli concentration on the lettuce was determined. After exclusion of an outlier with high E. coli levels (Most Probable Number = 5.94*108), the average percent of E. coli in the feces that transferred to intact lettuce heads was 0.0267% (Standard Error [SE] = 0.0172). Log-linear regression showed that significantly more E. coli transferred to outer leaves compared to inner leaves (Effect = 1.3; 95% Confidence Interval = 0.4, 2.1). Additionally, the percent of E. coli that transferred from the feces to the lettuce decreased significantly with time after fecal placement, and as the distance between the lettuce and the feces, and the lettuce and the sprinklers increased. These findings provide key data that may be used in future quantitative risk assessments to identify potential intervention strategies for reducing food safety risks associated with fresh produce.

UR - http://www.scopus.com/inward/record.url?scp=85021650276&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85021650276&partnerID=8YFLogxK

U2 - 10.1016/j.fm.2017.06.009

DO - 10.1016/j.fm.2017.06.009

M3 - Article

C2 - 28800822

AN - SCOPUS:85021650276

VL - 68

SP - 24

EP - 33

JO - Food Microbiology

JF - Food Microbiology

SN - 0740-0020

ER -