title: An Evaluation of Molybdenum Toxicity to the Oligochaete, Tubifex tubifex, and Early-Life Stages of Brown Trout, Salmo trutta.
abstract: Limited data are available describing the aquatic toxicity of molybdenum in freshwater environments, making it difficult to assess the aquatic risk to freshwater organisms. In order to increase available information on the aquatic toxicity of molybdenum, a 96-h LC50 test with the oligochaete Tubifex tubifex and an 85-day development test using brown trout, Salmo trutta, were conducted. The T. tubifex test resulted in an LC50 value of 2782 mg/L. No adverse effects were observed on brown trout survival or length in the concentrations tested, however an IC10 value for growth (wet weight) was determined to be 202 mg/L. Whole body fish tissue concentrations for molybdenum increased in all treatment concentrations tested, although bioconcentration factors decreased at greater exposure concentrations, and ranged from 0.13 at an exposure concentration of 20 mg/L to 0.04 at an exposure of 1247 mg/L. A body burden of 26.0 mg/kg was associated with reduced wet weight.
authors.affiliation: Nautilus Environmental Company Inc., 8664 Commerce Court, Burnaby, BC, V5A 4N7, Canada. brett@nautilusenvironmental.ca.
authors.forename: Brett T
authors.initials: BT
authors.lastname: Lucas
authors.affiliation: Nautilus Environmental Company Inc., 8664 Commerce Court, Burnaby, BC, V5A 4N7, Canada.
authors.forename: Claudio
authors.initials: C
authors.lastname: Quinteros
authors.affiliation: Cameco Corporation, 2121 11th Street West, Saskatoon, SK, S7M 1J3, Canada.
authors.forename: Charlene
authors.initials: C
authors.lastname: Burnett-Seidel
authors.affiliation: Nautilus Environmental Company Inc., 8664 Commerce Court, Burnaby, BC, V5A 4N7, Canada.
authors.forename: James R
authors.initials: JR
authors.lastname: Elphick
mesh_terms: D000818:Animals; D004784:Environmental Monitoring; D008982:Molybdenum / Q000633:toxicity*; D009835:Oligochaeta / Q000187:drug effects / Q000502:physiology*; D014337:Trout / Q000502:physiology*; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D014874:Water Pollutants, Chemical; D008982:Molybdenum
keywords: Aquatic toxicology; Bioaccumulation; Bioassay; Early-life stages; Metal accumulation; Molybdenum