1、Designation: D 4412 84 (Reapproved 2009)Standard Test Methods forSulfate-Reducing Bacteria in Water and Water-FormedDeposits1This standard is issued under the fixed designation D 4412; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision
2、, 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 These test methods cover the procedure for the detectionand enumeration by the most probable number (MPN
3、) tech-nique of sulfate-reducing bacteria in water or water-formeddeposits.1.2 Two media preparations are provided. Medium A whichis prepared with reagent grade water, and Medium B which isprepared using the water to be sampled as the water source.Medium B is offered for those special conditions whe
4、resulfate-reducing bacterial strains have adapted to atypicalnon-fresh water environment.1.3 For the isolation and enumeration of thermophilicsulfate-reducing bacteria encountered in waters associated withoil and gas production, all broths, dilution blanks, and incuba-tions must be maintained at tem
5、peratures of at least 45C andpreferably within 5C at the sample temperature.1.4 The sensitivity of these test methods can be increased bypurging the dilution blanks and tubes of media with nitrogenimmediately prior to use.1.5 The analyst should be aware that adequate collaborativedata for precision
6、and bias statements as required by PracticeD 2777 are not provided. See Section 11 for details.1.6 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.7 This standard does not purport to address all of thesafety concerns, if any,
7、associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 1129 Terminology Relating to WaterD 1193 Specificat
8、ion for Reagent WaterD 2777 Practice for Determination of Precision and Bias ofApplicable Test Methods of Committee D19 on Water2.2 APHA Standard:Standard Methods for the Examination of Water and Waste-water, Fifteenth Edition33. Terminology3.1 Definitions: For definitions of terms used in these tes
9、tmethods, refer to Terminology D 1129.3.2 Definitions of Terms Specific to This Standard: For adescription of the term MPN used in these test methods, referto literature.44. Summary of Test Methods4.1 Water and water deposit samples and dilutions of thesesamples are dispensed into tubes of Starkeys
10、medium (Aor B)following five tube MPN procedures. The tubes are sealed withliquid paraffin, and incubated at 20C for 21 days.4Positivereactions are indicated by the deposit of a black precipitate.5. Significance and Use5.1 Sulfate-reducing bacteria are widely distributed in ma-rine and fresh water m
11、uds which, in consequence, frequentlyare laden with the hydrogen sulfide produced by these organ-isms during dissimilatory sulfate reduction.5.2 It has been reported that Desulfovibrio can form asmuch as 10 g of sulfide per litre during active multiplication.Sulfate-reducing bacteria can cause the e
12、xternal or internalcorrosion of water or wastewater pipelines and pipelines forpetroleum and natural gas. The formation of galvanic cells bymassive growth of sulfate-reducing bacteria under suitableconditions makes the corrosion much worse than just the effectof the hydrogen sulfide on the metal or
13、concrete.6. Apparatus and Materials6.1 Anaerobic Incubator, 20C, if available, or conventional20C incubator.1These test methods are under the jurisdiction of ASTM Committee D19 onWater and are the direct responsibility of Subcommittee D19.24 on Water Micro-biology.Current edition approved May 1, 200
14、9. Published June 2009. Originallyapproved in 1984. Last previous edition approved in 2002 as D 4412 84 (2002).2For 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 s
15、tandards Document Summary page onthe ASTM website.3Available from American Public Health Association, 1015 18th St. N.W.,Washington, DC 20036.4Bonde, G. J., “Bacterial Indicators of Water Pollution,” A Study of QuantitativeEstimation, Teknisk Forlag, Copenhagen, 1963.1Copyright ASTM International, 1
16、00 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.NOTE 1For thermophilic organisms use a 45C incubator.6.2 Pipets, sterile, 1 mL and 10 mL, “calibrated” to deliver.6.3 Test Tubes, with close fitting or airtight caps; 16 by 150mm and 20 by 150 mm.6.4 Test Tube Racks,
17、of sufficient size to contain 16 and20-mm tubes.7. Reagents7.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents conform to the specifications of the Committee onAnalytical Reagents of the American Chemical Society,5whens
18、uch specifications are available.7.2 Purity of WaterUnless otherwise indicated, referencesto water shall be understood to mean Reagent Water Type IIconforming to Specification D 1193. In addition, reagent waterused for these test methods must be sterile.7.3 Starkeys Medium A6(modified):Sodium lactat
19、e (C3H5NaO3) 3.5 gAmmonium chloride (NH4Cl) 1.0 gDipotassium, hydrogen orthophosphate(K2HPO4)0.5 gMagnesium sulfate (MgSO47H2O) 2.0 gSodium sulfate (Na2SO4) 0.5 gCalcium chloride (CaCl22H2O) 0.1 gThioglycollic acid 0.1 gAmmonium ferrous sulfate or ferrousammonium sulfate(NH4)2SO4FeSO46H2O)0.001 gWat
20、er (H2O) 1 L7.3.1 Double strength medium (23) is prepared as aboveexcept 500 mL of water are used instead of 1 L.7.3.2 Heat to dissolve and dispense 9 mL of medium persingle strength tube, and 10 mL per double strength tube.7.3.3 Tubes should be of sufficient capacity to contain 1 mLof inoculum plus
21、 9 mL of single strength medium or 10 mL ofinoculum plus 10 mL of 23 medium.7.3.4 pH of medium should be 7.2 after autoclave steriliza-tion, at 121C for 15 min.7.4 Starkeys Medium BThe medium is similar to thatdescribed in 7.3, 7.3.1, and 7.3.2 with the following modifica-tion:7.4.1 Water collected
22、from the sample collection site is usedto prepare the medium outlined in 7.3. The water sample isfiltered to remove particulates (1.2 m membrane filter) and thepH is recorded.7.4.1.1 After preparing the Medium B following 7.3.1,7.3.2, and 7.3.3, and prior to dispensing, check and adjust pH,if necess
23、ary to that of the original water used, then filtersterilize the medium by passage through 0.2-m filter andasceptically dispense into presterilized tubes.7.5 Hydrogen Sulfide Test Reagent:7.5.1 Ferric Chloride Stock Solution (FeCl36H2O)Dissolve 13.5 g of ferric chloride in a mixture of 250 mL ofwate
24、r and 250 mL of HCl (sp gr 1.19). Store in an airtightamber container. Prepare fresh monthly.7.5.2 p-Aminodimethylaniline Dihydrochloride Stock Solu-tionp-Aminodimethylaniline dihydrochloride(C8H12N22HCl)1.0 gHCl (6 N) 500 mLDissolve1gofp-aminodimethylaniline dihydrochloride in500 mL of 6 N HCl. Sto
25、re for up to 1 month in an amberairtight container.7.6 Liquid ParaffnHeavy, sterile, or sterile mineral oil.7.7 Buffered Dilution WaterStock Solution7.7.1 Dissolve 34.0 g of KH2PO4in 500 mL of water, adjustpH to 7.2 with 1 N NaOH and dilute to 1 L with distilled water.This is called the stock phosph
26、ate solution.7.7.2 Dissolve 38 g of MgCL2in 1 L of distilled water.7.8 Buffered Dilution Water, Working SolutionAdd 1.25mL of stock buffered dilution water and 5 mL of MgCl2solution to 500 mL of water. Bring to 1 L with water. Mix welland dispense as 90 mL dilution blanks in screw-capped bottles.Ste
27、rilize by autoclaving at 121C for 15 min.8. Procedure8.1 Clean and disinfect the area with a cleaning solution thatleaves no residue.8.2 Set out and label five replicate tubes of 10-mL double-strength Starkeys medium, A or B, in the test tube rack.8.3 Set out and label five replicate tubes of 10-mL
28、single-strength Starkeys medium, A or B, for each mL of sample ormL of sample dilution to be tested. Use two sets of fivereplicate 10-mL tubes, each to contain 1 mL of sample or 1 mLof 1/10 dilution of sample.8.4 Prior to sample inoculation, heat tubes of media anddilution blanks in a water bath to
29、60C then cool rapidly to20C to ensure minimal oxygen levels.8.5 Shake sample thoroughly, at least 25 times; makedilutions starting with 10 mL of sample into one 90-mLdilution blank.NOTE 2Organisms do not appear to be hypersensitive to smallamounts of oxygen.8.6 Pipet 10 mL of sample into each double
30、-strength brothand 1 mL of sample or diluted sample into each set of fivesingle-strength broths.8.7 Maintain anaerobic conditions by layering 2 to 3 ml ofsterile liquid paraffin in each tube.8.8 Recap tubes and incubate at 20C for 21 days.8.9 Include sterile water samples with each test as negativec
31、ontrols.8.10 Positive reaction is indicated by the deposit of a blackprecipitate (sulfide).8.11 Confirm dubious results by the addition of 0.5 mL offerric chloride reagent followed by 0.5 mL ofp-aminodimethylaniline reagent to the MPN tube. Add reagentto the bottom of the tube using syringe or long
32、Pasteur pipet. Apositive reaction, blue color, occurs within 10 min if H2Sispresent.5Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For Suggestions on the testing of reagents notlisted by the American Chemical Society, see Annual Standards for
33、LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.6Starkey, R. L., “Characteristics and Cultivation of Sulfate-Reducing Bacteria,”Journal of the American Water Works Association , Vol
34、 40, 1948, pp. 12911298.D 4412 84 (2009)29. Calculation9.1 Compute the number of positive findings resulting frommultiple-portion decimal dilution planting as the combinationof positives and recorded in terms of the Most ProbableNumber3(MPN).9.2 When more than three series of tubes are employed in a
35、decimal series of dilutions, use the results from only three ofthese used in computing the MPN, for example:10mL1mL0.1mL0.01mL5/5 5/5 2/5 0/5 = 5-2-0 3 10 = 490/100 mL5/5 4/5 2/5 0/5 = 5-4-2 = 220/100 mL5/5 3/5 1/5 1/5 = 5-3-2 = 140/100 mL5/5 0/5 0/5 0/5 = 5-0-0 = 23/100 mL10. Report10.1 Report the
36、results as number of sulfate-reducing bac-teria per 100 mL of sample.11. Precision and Bias711.1 Due to the instability of the organisms, round robintesting can not be carried out. Statements can only be made onthe precision of the MPN procedure.11.2 Unless a large number of portions of sample areex
37、amined, the precision of the MPN is rather low. For example,even when the sample contains one organism per millilitre,about 37 % of tubes inoculated with 1 mL of sample may beexpected to yield negative results because of irregular distri-bution of the bacteria in the sample and the multiple attachme
38、ntof bacteria to particles. When five tubes, each with 1 mL ofsample, are employed under these conditions, a completelynegative result may be expected less than 1 % of the time.Thus, even when five tubes are employed for each dilution, theprecision of the results obtained is not of a high order.11.3
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42、e not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple
43、 copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).7Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR: D19-1116.D 4412 84 (2009)3