Designation:D5583–06StandardTestMethodforDetectionandEstimationofRetentionofWoodPreservativesbyAspergillusBioassaying1ThisstandardisissuedunderthefixeddesignationD5583;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(e)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethodcoversanon-chemical,biologicalprocedureforassayingwoodforapproximatepreservativecontent(Note1).Itrequiresminimalequipmentandtechnicalproficiency.Nocostlyequipmentisneededotherthanasmallautoclaveforpreparingfungalmedia.Sincethistestmethoddoesnotrequirecompositesamplestoascertainpreservationretentions,thereforeitisusedtoassessretentionatindividuallocations.NOTE1—Withappropriate,simpleadaptation,themethodcanbeusedwithotherproductsbesideswood,suchasfungicidalpaintsandglues.Theassayingisdonewhereveritisconvenient,sinceasepticprecautionsarenotrequiredexceptformaintainingapurestockcultureoftheassayfungus.1.2ThevaluesstatedinSIunitsaretoberegardedasthestandard.Theinch-poundunitsgiveninparenthesesareforinformationonly.1.3Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.SummaryofTestMethod2.1SmallwoodspecimensofprescribedsizeareplacedonnutrientagarinaPetridishfreshlyseededwithsporesofAspergillusniger,ablackmold,andthecultureisallowedtoincubateforthreetofourdays.Thefungusisunabletoproduceitstypicalblacksporesaroundsamplescontaininganinhibi-toryamountofpreservative;thisindicatesthepresenceofpreservative,andthesizeofthewhitearea(zoneofeffect)istheindexofpreservativeretention(seeFig.1andFig.2).Therelationofretentiontozoneofeffectisdeterminedforeachpreservative,fromassaysofspecimenscontainingagradientofretentionsofthepreservative.(Seeexampleforpent...
