B.W. Alsanius, A.K. Rosberg, L. Kristensen , M. Hultberg
Outbreaks of foodborne diseases (Norovirus, Salmonella spp., verotoxin producing E. coli, Campylobacter spp., Shigella spp.) related to fruit and vegetable consumption have increased worldwide. Contamination may occur at any point during the entire farm-to-fork continuum with irrigation water and organic manure as major routes for contamination. Microbial related sickness causes considerable and in some cases life-long suffering and death as well as substantial economic losses. In this study we focused on irrigation water quality from surface water sources. The study was divided into three parts (i) monitoring of the hygienic status of five surface water sources in Southern Sweden, (ii) selection of indicator organisms for an irrigation water quality criteria and (iii) improvement of surface water with inferior microbial quality. Water samples were collected in both a long- and short-term study and analyzed with respect to process indicators and indicators for short term and long term fecal contamination as well as enteric pathogens. Considerable variation occurred between and within sampling incidents and between categories of surface water sources, with lake and creek water as the most hazardous sources. Salmonella spp. was identified repeatedly in four of five surface water sources. Due to high similarity, E. coli may serve as a sole parameter for short term contamination. This together with the analysis of intestinal enterococci and Salmonella spp., should be integrated in a future risk assessment of surface water. Photocatalytic water treatment reduced the number of all indicator organisms and therefore appears to be a potential tool to improve surface water of inferior quality.
Alsanius, B.W., Rosberg, A.K., Kristensen , L. and Hultberg, M. (2011). PREHARVEST MEASURES FOR INCREASED BIOSAFETY OF FIELD GROWN CROPS. Acta Hortic. 922, 269-276
DOI: 10.17660/ActaHortic.2011.922.35
Escherichia coli, human pathogens, indicator organism, intestinal enterococci, irrigation water, photocatalytic treatment, Salmonella spp., surface water

Acta Horticulturae