ASTM_D_6503_-_19.pdf

Designation:D650319Standard Test Method forEnterococci in Water Using Enterolert1,2This standard is issued under the fixed designation D6503;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers a simple procedure for thedetection of enterococci in water and wastewater.It is based onIDEXXs patented Defined Substrate Technology(DST).2Thisproduct,Enterolert,utilizes a nutrient indicator that fluoresceswhen metabolized.It can detect these bacteria at one mostprobable number(MPN)/100 mL within 24 h.The presence ofthis microorganism in water is an indication of fecal contami-nation and the possible presence of enteric pathogens.1.2 This test method can be used successfully with drinkingwater,source water,recreational(fresh and marine)water,wastewater,and bottled water.It is the users responsibility toensure the validity of this test method for waters of untestedmatrices.1.3 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.4 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:3D1129 Terminology Relating to WaterD1193 Specification for Reagent WaterD2777 Practice for Determination of Precision and Bias ofApplicable Test Methods of Committee D19 on WaterD3370 Practices for Sampling Water from Flowing ProcessStreams3.Terminology3.1 DefinitionsFor definitions of terms used in this testmethod,refer to Terminology D1129.3.2 Definitions of Terms Specific to This Standard:3.2.1 enterococci,na gram positive bacteria possessingthe enzyme-D-glucosidase,which cleaves the nutrient indi-cator and produces fluorescence under a long wave length(365366 nm)ultraviolet(UV)light.3.2.2 most probable number(MPN),na statistical methodfor determining bacterial density based on the Poisson distri-bution.3.2.3 presence-absence,na term used to indicate if en-terococci are present or absent in a water sample.3.2.3.1 DiscussionIt is a qualitative value,“yes”or“no”for reporting results.3.2.4 Quanti-Tray,na system for the quantification ofenterococci.23.2.4.1 DiscussionIt consists of a sealer and trays whichhave multi-wells and can enumerate up to 2419 MPN/100 mLwithout dilution using the Quanti-Tray 2000 tray or it candetect up to 200.5 MPN/100 mL using the 51-well Quanti-Tray.3.2.5 snap pack,na package containing Enterolert reagentfor testing 100-mL sample either in the P/A format orquantitatively,with the Quanti-Tray system.4.Summary of Test Method4.1 This test method is used for the detection of enterococci,such as E.faecium,E.faecalis in drinking water,source water,recreational waters(marine water and fresh),wastewaters,andbottled water.When the reagent is added to the sample andincubated at 41 6 0.5C for 24 h and up to 28 h,Enterolert candetect these bacteria at 1 MPN/100 mL.Fluorescence isproduced when enterococci metabolizes the nutrient indicator.Enterolert can be used as a presence-absence test or forquantification(5-tube,10-tube MPN,15-tube serial dilution orthe Quanti-Tray system).1This test method is under the jurisdiction of ASTM Committee D19 on Waterand is the direct responsibility of Subcommittee D19.24 on Water Microbiology.Current edition approved April 1,2019.Published May 2019.Originallyapproved in 1999.Last previous edition approved in 2014 as D6503 14.DOI:10.1520/D6503-19.2Enterolert and Quanti-Tray are trademarks of IDEXX Laboratories,Inc.,inWestbrook,ME.3For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1 5.Significance and Use5.1 This test provides an easy and reliable method for thedetection of