Summary of Awards to Date

Science-based evaluation of regional risks for Salmonella contamination of irrigation water at mixed produce farms in the Suwannee River watershed.

Date

Oct. 1, 2010 - Jan. 31, 2013

Award Number

2011-148

Funding Agency

Center for Produce Safety

Amount Awarded

$313,513.00

Investigator

Anita Wright, Ph.D.
University of Florida

Co-Investigator(s)

A. Van Bruggen, P. Adams, M. Danyluk

Summary

Outbreaks of human illness associated with produce have resulted in questions about the safety
of the water used for irrigating these products. We have assembled an experienced team from the
University of Georgia at Tifton and the University of Florida to address the water quality of
vegetable irrigation ponds in the Suwannee River watershed. Irrigation water quality standards
are not currently regulated or determined by scientifically based metrics. Coliform bacteria are
widely used as indicators of fecal contamination, but their validity as indicators of bacterial
pathogens is questionable. We propose to investigate the relationship between the occurrence
and distribution of these indicator bacteria with that of a specific pathogen, namely Salmonella
enterica. Growers in this principal produce production area of the United States have agreed to
allow periodic collection of water samples from irrigation ponds to provide preliminary data and
validate methodologies. Proposed research will systematically examine bacteria in and around 10
irrigation pond sites for a two-year period under a variety of environmental conditions. This
research will identify management practices, environmental parameters, and locale
characteristics associated with increased risk of pathogen contamination by irrigation water and
will provide a research-based comparison of indicator organisms and Salmonella in a major fruit
and vegetable growing area.