Application of tangential flow ultrafiltration and molecular detection for the microbial evaluation of 100L surface and ground water samples impacted by industrial food animal production

One of the leading causes of death worldwide is infectious diseases, thus emerging human and animal microbial pathogens associated with waterborne transmission are of particular concern to the public health community. A major limiting factor in evaluating the microbial quality of various water sources is the lack of an effective and efficient method for simultaneous collection and recovery of low levels of bacteria, viruses, and protozoa and the subsequent inability of these isolated microbes to be rapidly identified and quantified. Current methods for the assessment of microorganisms in water are targeted towards specific pathogen groups. Our research applied tangential flow ultrafiltration (TFU) for the simultaneous concentration and recovery of microbes from large volumes (100L) of surface (SW) and ground water (GW) potentially impacted by animal wastes—a product of industrial food animal production practices. A TFU system designed to concentrate 100L water samples was optimized using a commercially available capsule filter containing hollow fiber membranes of 70,000-dalton pore size. The final concentrated sample (100-300mL) is analyzed using culture-based methods and/or molecular-based real time polymerase chain reaction (qPCR) and loop-mediated isothermal amplification (LAMP) for the identification of select, endogenous microorganisms including pathogenic bacteria, viruses, and protozoa of human health concern. Lower Yakima Valley, WA—a rural region with the densest concentration of dairy operations and milk cows in WA state—was selected for the application of TFU to 100L water samples (n=21). Bacterial analysis has been completed and viral and protozoa analysis is ongoing.