【英文标准名称】:StandardTestMethodforBiodegradationByaShake-FlaskDie-AwayMethod
【原文标准名称】:用摇瓶衰减弱法作生物降解的标准试验方法
【标准号】:ASTME1279-1989(2008)
【标准状态】:现行
【国别】:美国
【发布日期】:1989
【实施或试行日期】:
【发布单位】:美国材料与试验协会(US-ASTM)
【起草单位】:E47.04
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:
【英文主题词】:Abioticdegradation;Biologicaldataanalysis--sediments;Carboncontent;Chemicals(environmentalanalysis);Degradation--environmentalmaterials/applications;Die-awaybiodegradation;Equilibriumadsorptioncoefficient(Koc);Estuarineenviro
【摘要】:Mostofthesimplermethodsusedtoscreenchemicalsforbiodegradationpotentialemploymeasurementsthatarenotspecifictothetestsubstance,suchaslossofdissolvedorganiccarbon,evolutionofrespiratorycarbondioxide,oruptakeofdissolvedoxygen.Suchmethodsgenerallyareusedtoevaluatethetransformationofthetestsubstancetocarbondioxide,water,oxidesormineralsaltsofotherelements,orproductsassociatedwiththenormalmetabolicprocessesofmicroorganisms(ultimatebiodegradability),orboth.Thesemethodsrequiretheuseofrelativelyhighinitialconcentrationsofthetestsubstance,generally10mg/Lorhigher,unlessthetestsareconductedusing14C-radiolabeledtestcompounds.Biodegradationtestsmeasuring14C-CO2evolution,forexample,canbeconductedusinginitialconcentrationoftestcompoundatpartsperbillion.Thesetests,however,requirespecializedequipmentandthecustompreparationofappropriatelylabeledcompoundisoftenveryexpensive.Die-awaybiodegradationmethodsaresimplesimulationmethodsthatemploywatercollectedfromnaturalwatersourcesandfollowthedisappearanceofanaddedamountofthetestsubstanceresultingfromtheactivityofmicroorganismsinthewatersample.Thechemical-specificanalyticaltechniquesusedtofollowthedisappearanceofthetestsubstance,typicallyareemployedusingrelativelylowinitialconcentrationsofthetestsubstance.Mostenvironmentalpollutantsarepresentintheenvironmentatrelativelylowconcentrations(lessthan1mg/L)andithasbeenobservedthatbiodegradationratesobtainedusinghightestcompoundconcentrationsmaybequitedifferentfromthoseobservedatlowerconcentrations(6).Thetransformationofthetestsubstancetoanextentsufficienttoremovesomecharacteristicpropertyofthemolecule,resultinginthelossofdetectionbythechemicalspecificanalyticaltechnique,isreferredtoasprimarybiodegradation.Formanypurposes,evidenceofprimarybiodegradationissufficient,especiallywhenitisknownorcanbeshownthattoxicity,orsomeotherundesirablefeature,associatedwiththetestcompoundisremovedorsignificantlyreducedasaresultoftheprimarybiodegradation.Adeterminationofultimatebiodegradation,ontheotherhand,isusuallyrequiredonlywhentreatabilityororganicloadingareissuesofconcern.Furthermore,manyofthesimplermethods,suchasthosemeasuringCO2evolution(see4.1),maynotdetectprimarybiodegradation.Theuseoflowsubstrateconcentrationenhancestheprobabilityofobservingfirst-order,orpseudofirst-order,kinetics.Thus,arateconstantfortheprimarybiodegradationreactionandahalf-lifecanbederivedfromthetestcompoundunderdefinedincubationconditions.Rateconstantsarerequiredinmanyenvironmentalfatemathematicalmodels.1.1Thistestmethoddescribesproceduresforassessingthebiodegradationofchemicalsinnaturalsurfacewatersamples.1.2Thistestmethodprovidesanopportunitytoevaluateratesofbiodegradationinthepresenceandabsenceofnaturalsedimentmaterials.Italsomayprovidelimitedinformationontheabioticdegradationrate,andsorptiontosedimentandvesselwalls.1.3Thistestmethodallowsforthedevelopmentofafirst-orderrateconstant,basedonthedisappearanceofthetestcompoundwithtime,andasecond-orderrateconstant,normalizedforchangesinmicrobialbiomass.1.4Thistestmethodrequiresachemicalspecificanalyticalmethodandtheconcentrationsoftestsubstanceemployedaredependentonthesensitivityoftheanalyticalmethod.1.5Thistestmethodisdesignedtobeapplicabletocompoundsthatarenotinhibitorytobacteriaattheconcentrationsusedinthetestm......
【中国标准分类号】:Z19
【国际标准分类号】:13_030_40
【页数】:5P.;A4
【正文语种】:英语