Comparative Assessment of the Microbial  Quality of Agricultural Water on Kansas and Missouri Fresh Produce Farms

In 2015, the U.S. States Food and Drug Administra-tion published the Produce Safety Rule (PSR), providing guidance for growers to minimize food safety risks as-sociated with growing, harvesting, packing, and holding fresh produce. To mitigate foodborne outbreaks attribut-ed to contaminated agricultural water, the PSR requires growers to test their water for microbial contamination. The increased production of fruits and vegetables in Kansas and Missouri necessitates the investigation of agricultural water quality in these states. This study assessed and compared the prevalence of generic Escherichia coli in agricultural water sources in both states. A total of 426 agricultural water samples were analyzed using the IDEXX Colilert with Quanti-Tray/2000 method. Although there were no statistically significant differences in the prevalence of E. coli in agricultural waters detected between the two states (P < 0.4023), the average number of E. coli in surface water sourc-es (158.7 most probable number [MPN]/100 mL, n = 247) was statistically greater than that of groundwater sources (20.4 MPN/100 mL, n = 179, P < 0.0001), and seasonal effects were detected (P < 0.0001). These results demonstrate the higher microbial risk of surface water compared with groundwater in both states and the need for continued grower education on safe water management practices.