State Water Resources Research Institute Program
Project ID: 2007WA210B
Title: Assessment of contaminated sediments using a rainbow trout (Oncorhynchus mykiss) as an embryonic exposure assay
Project Type: Research
Start Date: 3/01/2007
End Date: 2/28/2008
Congressional District: Washington Fifth
Focus Categories: Sediments, Toxic Substances, Water Quality
Keywords: Contaminated sediments, toxicology, PCBs, PBDEs
Principal Investigator: Ullman, Jeffrey Layton
Federal Funds: $ 24,000
Non-Federal Matching Funds: $ 48,077
Abstract: Despite contaminated sediments presenting an environmental health hazard, ecological risk assessments remain largely impeded by a lack of data and guidance. The state of Washington has adopted a robust system of standards to handle marine sediments, but freshwater sediment evaluation remains on a case-by-case basis. Since sediments display temporal variability and bioavailability can not be directly linked to total contaminant load, more information on the effects of direct contact exposure to sediments by benthic organisms is needed.
Rainbow trout (Oncorhynchus mykiss) have been used extensively as a toxicological model for assessing water quality due to low husbandry costs, sensitivity to pollutants and easily quantified physiological responses to contaminants. Due to inadequacies of LD50 values (dose response that results in 50% lethality), use of early life stage (ELS) toxicity analysis has increased as a tool to characterize risk in aquatic ecosystems. However, no published studies were found addressing the use of rainbow trout embryos to evaluate toxicity associated with direct contact with sediments.
This project hypothesizes that sub-lethal concentrations of organic contaminants associated with sediments will yield quantifiable health impacts using a variety of indices. Two classes of chemicals, polycyclic aromatic hydrocarbons (PAHs) and polybrominated diphenyl ethers (PDBEs), will be used separately and together to determine synergistic effects. Survival, fluctuating asymmetry, sex reversal, vitellogenin production and embryonic uptake will be examined using all-male clonal lines. This novel approach will provide insight into the toxicological and physiological effects of these compounds, as well as assess the feasibility of using this strategy as an alternative bioassay to determine sediment toxicity. Corresponding examination of sorption behavior of the organic compounds will provide further insight into the bioavailability of sediment-bound pollutants.
Progress/Completion Report, PDF