Microbial Hazards in Irrigation Water: Standards, Norms, and Testing to Manage Use of Water in Fresh Produce Primary Production

Abstract

Accessibility to abundant sources of high-quality water is integral to the production of safe and wholesome fresh produce. However, access to safe water is becoming increasingly difficult in many parts of the world, and this can lead to the production of fresh produce contaminated with pathogenic microorganisms, resulting in increased risk of human disease. Water, an important raw material in the fresh produce chain, is used in considerable amounts in many operations, including irrigation and application of pesticides and fertilizers, but also as a transport medium and for cooling and washing in postharvest practices. In several reported outbreaks related to uncooked fruit and vegetable products, water has been identified as a likely source of the outbreak. The present study, initiated by the ILSI Europe Emerging Microbiological Issues Task Force in collaboration with 8 other ILSI branches and support of WHO/FAO, was undertaken to review the status of, and provide suggestions for, consideration by different stakeholders on water and sanitation and its impact on food safety and public health. A limited number of guidelines and regulations on water quality for agricultural production are available, and many of them are still heavily based on microbial standards and (debated) parameters such as fecal coliforms. Data gaps have been identified with regard to baseline studies of microbial pathogens in water sources in many regions, the need for agreement on methods and microbial parameters to be used in assessing water quality, the fate of pathogens in water, and their transfer and persistence on irrigated/processed produce.

Assessment of irrigation water quality and microbiological safety of leafy greens in different production systems

“…Sources of water used for irrigation can include rain, ground, surface, and wastewater (Gelting et al, ; Ijabadeniyi, Debusho, Van der Linde, & Buya, ). Presence of pathogens in these water sources has recently attracted attention (Uyttendaele et al, ) due to the associated disease outbreaks linking contaminated water with fresh produce (Gelting et al, ). Irrigation water contaminated with animal feces and human waste is considered one possible route of preharvest vegetable contamination (Olaimat & Holley, ).…”

Spatiotemporal Variability in Microbial Quality of Western US Agricultural Water Supplies: A Multistate Study

“…Notwithstanding this gap in knowledge, irrigation water has long been regarded as an important vehicle for pathogens associated with foodborne illnesses (Uyttendaele et al, 2015). According to the Centers for Disease Control and Prevention, outbreaks that occurred during 2013 to 2014 from drinking water systems solely supplied by surface water accounted for nearly 80% of reported cases (Allende and Monaghan, 2015; Benedict et al, 2017; Uyttendaele et al, 2015). However, there is a paucity of research capable of linking microbial contamination in irrigation water to foodborne outbreaks in the United States (Pachepsky et al, 2016; Partyka et al, 2018).…”

Risk Assessment or Assessment of Risk? Developing an Evidence-Based Approach for Primary Producers of Leafy Vegetables To Assess and Manage Microbial Risks

“…A review of risks posed by food of nonanimal origin revealed that the main hazards to consider in leafy salads are Salmonella and norovirus (10). Uyttendaele et al (36) identified E. coli O157, Salmonella, norovirus, and Cyclospora cayetanensis as the main causes FIOs associated with leafy salad. In these cases, the most probable route of contamination (i.e., risk factor) of the produce was through direct or indirect fecal contamination from infected livestock or workers.…”

“…Alternatively, the grower could monitor irrigated soil for indicator species, investigate use of a relatively safer water source, avoid the use of uncontrolled surface water, or treat the water (1,36). This last option is presented in scenario 2.…”