title: Intra- and interlaboratory variability in acute toxicity tests with glochidia and juveniles of freshwater mussels (Unionidae).
abstract: The present study evaluated the performance and variability in acute toxicity tests with glochidia and newly transformed juvenile mussels using the standard methods outlined in American Society for Testing and Materials (ASTM). Multiple 48-h toxicity tests with glochidia and 96-h tests with juvenile mussels were conducted within a single laboratory and among five laboratories. All tests met the test acceptability requirements (e.g., >or=90% control survival). Intralaboratory tests were conducted over two consecutive mussel-spawning seasons with mucket (Actinonaias ligamentina) or fatmucket (Lampsilis siliquoidea) using copper, ammonia, or chlorine as a toxicant. For the glochidia of both species, the variability of intralaboratory median effective concentrations (EC50s) for the three toxicants, expressed as the coefficient of variation (CV), ranged from 14 to 27% in 24-h exposures and from 13 to 36% in 48-h exposures. The intralaboratory CV of copper EC50s for juvenile fatmucket was 24% in 48-h exposures and 13% in 96-h exposures. Interlaboratory tests were conducted with fatmucket glochidia and juveniles by five laboratories using copper as a toxicant. The interlaboratory CV of copper EC50s for glochidia was 13% in 24-h exposures and 24% in 48-h exposures, and the interlaboratory CV for juveniles was 22% in 48-h exposures and 42% in 96-h exposures. The high completion success and the overall low variability in test results indicate that the test methods have acceptable precision and can be performed routinely.
authors.affiliation: Columbia Environmental Research Center, U.S. Geological Survey, New Haven Road, Columbia, Missouri 65201, USA. nwang@usgs.gov
authors.forename: Ning
authors.initials: N
authors.lastname: Wang
authors.forename: Tom
authors.initials: T
authors.lastname: Augspurger
authors.forename: M Chris
authors.initials: MC
authors.lastname: Barnhart
authors.forename: Joseph R
authors.initials: JR
authors.lastname: Bidwell
authors.forename: W Gregory
authors.initials: WG
authors.lastname: Cope
authors.forename: F James
authors.initials: FJ
authors.lastname: Dwyer
authors.forename: Steve
authors.initials: S
authors.lastname: Geis
authors.forename: I Eugene
authors.initials: IE
authors.lastname: Greer
authors.forename: Chris G
authors.initials: CG
authors.lastname: Ingersoll
authors.forename: Cynthia M
authors.initials: CM
authors.lastname: Kane
authors.forename: Thomas W
authors.initials: TW
authors.lastname: May
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Neves
authors.forename: Teresa J
authors.initials: TJ
authors.lastname: Newton
authors.forename: Andy D
authors.initials: AD
authors.lastname: Roberts
authors.forename: David W
authors.initials: DW
authors.lastname: Whites
mesh_terms: D000818:Animals; D049872:Bivalvia / Q000187:drug effects* / Q000254:growth & development; D005618:Fresh Water; D007753:Laboratories; D007814:Larva / Q000187:drug effects; D018675:Toxicity Tests / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D014874:Water Pollutants, Chemical