Designation:E2455−06(Reapproved2013)StandardGuideforConductingLaboratoryToxicityTestswithFreshwaterMussels1ThisstandardisissuedunderthefixeddesignationE2455;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thisstandardguidedescribesmethodsforconductinglaboratorytoxicitytestswithearlylifestagesoffreshwatermusselsincludingglochidiaandjuvenilemusselsinwater-onlyexposures(AnnexA1).Futurerevisionstothisstandardmaydescribemethodsforconductingtoxicitytestswith(1)adultfreshwatermusselsand(2)contaminatedsedimentsusingvariouslifestagesoffreshwatermussels.1.2ManyfactorsarecitedaspotentiallycontributingtothedeclineoffreshwatermusselpopulationsinNorthAmerica.Ofthenearly300taxaoffreshwatermusselsinNorthAmerica,70species(23%)arelistedasendangeredorthreatenedandanother40species(14%)arecandidatesforpossiblelisting(Williamsetal1993(1);Neves1997,2004(2,3)).2Habitatalteration,introductionofexoticspecies,over-utilization,disease,predationandpollutionareconsideredcausalorcontributingfactorsinmanyareasoftheUnitedStates(Nevesetal1997)(4).Overthepastdecade,therehavebeenover75publishedstudiesconductedthathaveevaluatedtheroleofcontaminantsinthedeclineofpopulationsoffreshwatermussels(Kernaghanetal2005)(5).Inthesestudies,earlylifestagesofmusselsofseveralspeciesarehighlysensitivetosomemetalsandammoniainwaterexposureswhencomparedtomanyofthemostsensitivespeciesofotherinvertebrates,fish,oramphibiansthatarecommonlyusedtoestablishU.S.EnvironmentalProtectionAgencyWaterQualityCriteria(WQC;Augspurgeretal2003(6),Kelleretal2005(7),Kernaghanetal2005(5);USGS(2005a,b)(8,9)section1.5).Importantly,resultsofthesepreviousstudiesindicateWQCforindividualchemicalsestablishedfortheprotectionofaquaticorganismsmaynotbeadequatelyprotectiveofsensitivestagesoffreshwatermussels.1.3SummaryofLifeHistoryofF...
