title: Predictive modeling of selenium accumulation in brine shrimp in saline environments.
abstract: Great Salt Lake, Utah, is a large, terminal, hypersaline lake consisting of a northern more saline arm and a southern arm that is less saline. The southern arm supports a seasonally abundant fauna of low diversity consisting of brine shrimp (Artemia franciscana), 7 species of brine flies, and multiple species of algae. Although fish cannot survive in the main body of the lake, the lake is highly productive, and brine shrimp and brine fly populations support large numbers of migratory waterfowl and shorebirds, as well as resident waterfowl, shorebirds, and gulls. Selenium and other trace elements, metals, and nutrients are contaminants of concern for the lake because of their concentrations in municipal and industrial outfalls and runoff from local agriculture and the large urban area of Salt Lake City. As a consequence, the State of Utah recently recommended water quality standards for Se for the southern arm of Great Salt Lake based on exposure and risk to birds. The tissue-based recommendations (as measured in bird eggs) were based on the understanding that Se toxicity is predominately expressed through dietary exposure, and that the breeding shorebirds, waterfowl, and gulls of the lake are the receptors of most concern. The bird egg-based recommended standards for Se require a model to link bird egg Se concentrations to their dietary concentrations and water column values. This study analyzes available brine shrimp tissue Se data from a variety of sources, along with waterborne and water particulate (potential brine shrimp diet) Se concentrations, in an attempt to develop a model to predict brine shrimp Se concentrations from the Se concentrations in surrounding water. The model can serve as a tool for linking the tissue-based water quality standards of a key dietary item to waterborne concentrations. The results were compared to other laboratory and field-based models to predict brine shrimp tissue Se concentrations from ambient water and their diet. No significant relationships were found between brine shrimp and their dietary Se, as measured by seston concentrations. The final linear and piecewise regression models showed significant positive relationships between waterborne and brine shrimp tissue Se concentrations but with a very weak predictive ability for waterborne concentrations<10 µg/L.
authors.affiliation: CH2M Hill, 2485 Natomas Park Drive, Suite 600, Sacramento, California 95833, USA. ebyron@ch2m.com
authors.forename: Earl R
authors.initials: ER
authors.lastname: Byron
authors.forename: Harry M
authors.initials: HM
authors.lastname: Ohlendorf
authors.forename: Aaron
authors.initials: A
authors.lastname: Redman
authors.forename: William J
authors.initials: WJ
authors.lastname: Adams
authors.forename: Brad
authors.initials: B
authors.lastname: Marden
authors.forename: Martin
authors.initials: M
authors.lastname: Grosell
authors.forename: Marjorie L
authors.initials: ML
authors.lastname: Brooks
mesh_terms: D000818:Animals; D001156:Artemia / Q000378:metabolism*; D004032:Diet; D008954:Models, Biological; D012044:Regression Analysis; D054712:Salinity; D012643:Selenium / Q000378:metabolism*; D014867:Water / Q000737:chemistry
chemical_list: D014867:Water; D012643:Selenium