Sludge Watch ==> Research publications: contaminated irrigation water - Ecoli0157 can persist - internalize in crops

[Maureen Reilly]

Applied and Environmental Microbiology, January 2002, p. 397-400, Vol. 68, 
No. 1
0099-2240/02/$04.00+0     DOI: 10.1128/AEM.68.1.397-400.2002
Copyright © 2002, American Society for Microbiology. All Rights Reserved.

Transmission of Escherichia coli O157:H7 from Contaminated Manure and 
Irrigation Water to Lettuce Plant Tissue and Its Subsequent Internalization
Ethan B. Solomon, Sima Yaron, and Karl R. Matthews*
Department of Food Science, Rutgers University, New Brunswick, New Jersey 
08901
The transmission of Escherichia coli O157:H7 from manure-contaminated soil 
and irrigation water to lettuce plants was demonstrated using laser scanning 
confocal microscopy, epifluorescence microscopy, and recovery of viable 
cells from the inner tissues of plants. E. coli O157:H7 migrated to internal 
locations in plant tissue and was thus protected from the action of 
sanitizing agents by virtue of its inaccessibility. Experiments demonstrate 
that E. coli O157:H7 can enter the lettuce plant through the root system and 
migrate throughout the edible portion of the plant.

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Letters in Applied Microbiology
Online Early
doi:10.1111/j.1472-765X.2006.01997.x



ORIGINAL ARTICLE
Use of repetitive DNA sequences to determine the persistence of 
enteropathogenic Escherichia coli in vegetables and in soil grown in fields 
treated with contaminated irrigation water
K. Ibenyassine1, R. AitMhand1, Y. Karamoko1, N. Cohen2 and M.M. Ennaji1
 Abstract

Aims: Fresh fruits and vegetables are increasingly recognized as vectors for 
food-borne illness. On farm contamination through contaminated irrigation 
water is considered likely source of the pathogen for several outbreaks. The 
purpose of this study is to investigate the possible similarity of strains 
of Escherichia coli isolated from the soil and vegetables irrigated by 
treated wastewater.
Methods and Results: Seventy-five strains of enteropathogenic Escherichia 
coli isolated from vegetables, soil and irrigation water were tested for 
sensitivity to antibiotics and shown to be sensitive. The result of 
enterobacterial repetitive intergenic consensus (ERIC)-PCR shows 
similarities between analysed strains isolated from the three different 
samples. Moreover strains of E. coli isolated from vegetables over different 
periods of time have the same ERIC-PCR profile.
Conclusions: The isolated strains of enteropathogenic E. coli can persist in 
soil and in vegetables growing in fields treated with contaminated 
irrigation water for an extended period of time.
Significance and Impact of the Study: Contaminated irrigation water can 
transport pathogenic bacteria, which persists in the soil for a long period 
of time and contaminates the vegetables growing in the field irrigated by 
this contaminated water.
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