title: Assessing variability in chemical acute toxicity of unionid mussels: Influence of intra- and interlaboratory testing, life stage, and species.
abstract: The authors developed a toxicity database for unionid mussels to examine the extent of intra- and interlaboratory variability in acute toxicity tests with mussel larvae (glochidia) and juveniles; the extent of differential sensitivity of the 2 life stages; and the variation in sensitivity among commonly tested mussels (Lampsilis siliquoidea, Utterbackia imbecillis, and Villosa iris), commonly tested cladocerans (Daphnia magna and Ceriodaphnia dubia), and fish (Oncorhynchus mykiss, Pimephales promelas, and Lepomis macrochirus). The results of these analyses indicate that intralaboratory variability for median effect concentrations (EC50) averaged about 2-fold for both life stages, whereas interlaboratory variability averaged 3.6-fold for juvenile mussels and 6.3-fold for glochidia. The EC50s for juveniles and glochidia were within a factor of 2 of each other for 50% of paired records across chemicals, with juveniles more sensitive than glochidia by more than 2-fold for 33% of the comparisons made between life stages. There was a high concurrence of sensitivity of commonly tested L. siliquoidea, U. imbecillis, and V. iris to that of other mussels. However, this concurrence decreased as the taxonomic distance of the commonly tested cladocerans and fish to mussels increased. The compiled mussel database and determination of data variability will advance risk assessments by including more robust species sensitivity distributions, interspecies correlation estimates, and availability of taxon-specific empirically derived application factors for risk assessment.
authors.affiliation: Gulf Ecology Division, US Environmental Protection Agency, Gulf Breeze, Florida.
authors.forename: Sandy
authors.initials: S
authors.lastname: Raimondo
authors.affiliation: Gulf Ecology Division, US Environmental Protection Agency, Gulf Breeze, Florida.
authors.forename: Crystal R
authors.initials: CR
authors.lastname: Lilavois
authors.affiliation: Gulf Ecology Division, US Environmental Protection Agency, Gulf Breeze, Florida.
authors.forename: Larisa
authors.initials: L
authors.lastname: Lee
authors.affiliation: US Fish and Wildlife Service, Raleigh, North Carolina.
authors.forename: Tom
authors.initials: T
authors.lastname: Augspurger
authors.affiliation: US Geological Survey, Columbia, Missouri.
authors.forename: Ning
authors.initials: N
authors.lastname: Wang
authors.affiliation: US Geological Survey, Columbia, Missouri.
authors.forename: Chris G
authors.initials: CG
authors.lastname: Ingersoll
authors.affiliation: US Environmental Protection Agency, Chicago, Illinois.
authors.forename: Candice
authors.initials: C
authors.lastname: Bauer
authors.affiliation: US Environmental Protection Agency, Chicago, Illinois.
authors.forename: Edward
authors.initials: E
authors.lastname: Hammer
authors.affiliation: Gulf Ecology Division, US Environmental Protection Agency, Gulf Breeze, Florida.
authors.forename: Mace G
authors.initials: MG
authors.lastname: Barron
mesh_terms: D000375:Aging; D000818:Animals; D049872:Bivalvia / Q000254:growth & development* / Q000378:metabolism*; D033361:Cladocera; D003621:Daphnia; D016208:Databases, Factual; D005399:Fishes; D005618:Fresh Water; D007814:Larva / Q000187:drug effects; D015203:Reproducibility of Results; D013045:Species Specificity; D023382:Toxicity Tests, Acute / Q000379:methods*; D049876:Unionidae / Q000254:growth & development* / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D014874:Water Pollutants, Chemical
keywords: Freshwater toxicity; Life stages; Mussels; Species extrapolation; Variability