July 29, 2004: Researchers
in the United Kingdom collected and tested 3,200 samples of raw
organic vegetables for microbial contamination and found 15, or
0.5 percent of those samples to be contaminated, testing positive
for either E. Coli or Listeria ssp.
While food poisoning incidents attributed to fruits and vegetables
in general are relatively low—only 1.4 percent to 3 percent
of outbreaks reported in the U.S. with similar figures reported
for Europe*—they still remain a concern for consumers. Organic
produce in particular has been questioned because of its close relationship
to manure, a common carrier of microbial pathogens, especially E.
Coli. The goal of the study was to determine the actual risk
posed by organic produce.
S.K. Sagoo and associates from the Environment Surveillance Unit
in London gathered and tested 3,200 samples of vegetables from retail
outlets ranging from supermarkets to doorstep box-scheme deliveries.
All vegetables shared two common characteristics: They could be
consumed with only light washing, and they were either grown in
close proximity of the soil or were a common salad vegetable such
as cucumber, pepper or tomato. British Standards were used to determine
The researchers found E. coli to be present in 1.5 percent
of the samples but at contamination level in only 0.3 percent, or
11, of the 3200 samples tested, while Listeria spp. (not
including L. monocytogenes) was detected in six samples
and considered contaminating in four of those samples Listeria
monocytogenes, Salmonella spp., Campylobacter
spp., and E. Coli O157 were not detected in any of the
*Figures from the European Commission Scientific Committee
on Food’s Risk Profile on the Microbiological Contamination
of Fruits and Vegetables Eaten Raw, April 2004.
Sagoo, S. K., et al., 2001. The microbiological examination of
ready-to-eat organic vegetables from retail establishments in the
United Kingdom. The Society for Applied Microbiology (33)