BCS Laboratories Inc. - Gainesville
4609 NW 6th Street, Bldg A, Gainesville, Florida 32609
FL DOH Laboratory #E82924, EPA# FL01147
(1) Three micron green fluorescent latex beads (Fluoresbrite® YG Microspheres 3.00μm, PolySciences Inc. PA, USA) were used as surrogates for Cryptosporidium oocysts. The beads were enumerated by fixing onto SingleSpot Slides (IDEXX, USA) and viewing by UV fluorescence microscopy.
(2) Raoultella terrigena (ATCC 33257) was obtained from ATCC and propagated Tryptic Soy Agar (TSA, Becton Dickinson, USA). The bacteria were enumerated as colony forming units (cfu) following incubation at 36.5°C for 24 hours.
(3) Bacteriophage MS-2 was used as a model for human viruses. It is a similar shape and size to human enterovirses and thus is used to determine filters viral capture efficacy. It was enumerated using E. coli C3000 as a host using the single layer plaque assay agar procedure as per EPA 1602.
*5 liters of City of Gainesville (FL) tap water were passed through the filter at a flow rate of 10 ml/ second using 40-60 mm HG provided by a diaphragm pressure pump (Stratagene Pressure Station). The water was passed by filling the sport bottle with water and attaching the filter then inverting. The bottom of the bottle was attached to the pressure source and thus the water was passed through the filter. Five hundred milliliters of Class I ASTM waters was placed into a sterile beaker and seeded with Raoultella terrigena,MS2 bacteriophage, andFlouresbrite® beads. This solution was agitated and 500ml placed into the sport bottle, connected to the filter top, and the solution was passed through the filter at 100 mm HG pressure. The flow rate was approximately 10 ml/sec. The effluent was collected and assayed for the respective species. A sample of the influent was removed prior to the beginning of the challenge study and at the end. The number of microorganisms and beads was determined and is reported as the “Filter Influent Water” and “Filter Effluent Water”. All analysis was conducted in duplicate.