Work Item
ASTM WK83403
New Test Method for the Quantification of Culturable Waterborne Bacteria Using a Defined Culture Medium Coated Plate
1. Scope
This test method describes a simple procedure for the quantification of culturable, waterborne bacteria in potable water (drinking water, bottled water, and dental water, for example) and non-potable waters (cooling towers, for example). The format is designed to test 1 milliliter of water sample on a grided plate containing a growth reagent embedded to the plate’s inner surface. The detection is based on colorimetric technology, where viable, aerobic waterborne bacteria (i.e., heterotrophs) grow when present in the water sample, displaying a color reaction allowing for a simplified visualization of colony growth. The sample is added directly to the plate, incubated, and then enumerated by counting the total number of all colonies, regardless of color. Each plate can accurately detect up to 300 colony forming units per 1 mL (CFU / 1 mL) of sample.
Keywords
bottled water; confluent growth; cooling towers; counting colonies; dental water; drinking water; EasyDisc PCA; EasyDisc R2A; EasyDisc YEA; heterotrophic plate count; pour plate; Reasoners 2 Agar (R2A); total plate count; total viable count; Yeast Extract Agar; Plate Count Agar
Rationale
This test method is useful for the routine monitoring of culturable waterborne bacteria in potable and non-potable waters. The significance of finding these bacteria can help with identifying water quality or water system problems or help evaluate compliance with maintenance protocols. This method uses small volumes of water, or dilutions thereof, and provides an easy and reliable method that eliminates media preparation and reduces laboratory waste.
The title and scope are in draft form and are under development within this ASTM Committee.
Work Item Status
Date Initiated: 09-09-2022
Technical Contact: Jody Frymire
Item: 001
Ballot: D19.24 (23-02)
Status: Item Going To Next Ballot Level