title: Measured Copper Toxicity to Cnesterodon decemmaculatus (Pisces: Poeciliidae) and Predicted by Biotic Ligand Model in Pilcomayo River Water: A Step for a Cross-Fish-Species Extrapolation.
abstract: In order to determine copper toxicity (LC50) to a local species (Cnesterodon decemmaculatus) in the South American Pilcomayo River water and evaluate a cross-fish-species extrapolation of Biotic Ligand Model, a 96 h acute copper toxicity test was performed. The dissolved copper concentrations tested were 0.05, 0.19, 0.39, 0.61, 0.73, 1.01, and 1.42 mg Cu L(-1). The 96 h Cu LC50 calculated was 0.655 mg L(-1) (0.823 - 0.488). 96-h Cu LC50 predicted by BLM for Pimephales promelas was 0.722 mg L(-1). Analysis of the inter-seasonal variation of the main water quality parameters indicates that a higher protective effect of calcium, magnesium, sodium, sulphate, and chloride is expected during the dry season. The very high load of total suspended solids in this river might be a key factor in determining copper distribution between solid and solution phases. A cross-fish-species extrapolation of copper BLM is valid within the water quality parameters and experimental conditions of this toxicity test.
authors.affiliation: Bernardino Rivadavia National Museum of Natural History, Avenida Angel Gallardo 470, C1405DJR Buenos Aires, Argentina.
authors.forename: María Victoria
authors.initials: MV
authors.lastname: Casares
authors.forename: Laura I
authors.initials: LI
authors.lastname: de Cabo
authors.forename: Rafael S
authors.initials: RS
authors.lastname: Seoane
authors.forename: Oscar E
authors.initials: OE
authors.lastname: Natale
authors.forename: Milagros
authors.initials: M
authors.lastname: Castro Ríos
authors.forename: Cristian
authors.initials: C
authors.lastname: Weigandt
authors.forename: Alicia F
authors.initials: AF
authors.lastname: de Iorio