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Farmington Hills, MI, United States

Rosen G.,Space and Naval Warfare Systems Center Pacific | Bart Chadwick D.,Space and Naval Warfare Systems Center Pacific | Allen Burton G.,University of Michigan | Keith Taulbee W.,University of Michigan | And 4 more authors.
Environmental Pollution | Year: 2012

A comprehensive, weight-of-evidence based ecological risk assessment approach integrating laboratory and in situ bioaccumulation and toxicity testing, passive sampler devices, hydrological characterization tools, continuous water quality sensing, and multi-phase chemical analyses was evaluated. The test site used to demonstrate the approach was a shallow estuarine wetland where groundwater seepage and elevated organic and inorganic contaminants were of potential concern. Although groundwater was discharging into the surficial sediments, little to no chemical contamination was associated with the infiltrating groundwater. Results from bulk chemistry analysis, toxicity testing, and bioaccumulation, however, suggested possible PAH toxicity at one station, which might have been enhanced by UV photoactivation, explaining the differences between in situ and laboratory amphipod survival. Concurrently deployed PAH bioaccumulation on solid-phase micro-extraction fibers positively correlated (r 2 ≥ 0.977) with in situ PAH bioaccumulation in amphipods, attesting to their utility as biomimetics, and contributing to the overall improved linkage between exposure and effects demonstrated by this approach. © 2011 Elsevier Ltd. All rights reserved. Source


Costello D.M.,University of Michigan | Burton G.A.,University of Michigan | Hammerschmidt C.R.,Wright State University | Taulbee W.K.,Great Lakes Environmental Center
Environmental Science and Technology | Year: 2012

Diffusive gradients in thin films (DGTs) rapidly measure labile fractions of metal and are promoted as an assessment tool for bioavailability. Using macroinvertebrate community composition as a response, this study compared the predictive ability of DGT-measured Ni with acid volatile sulfide (AVS) and organic carbon (OC) corrected Ni [(SEMNi-AVS)/fOC] and total Ni concentrations. In two experiments, sediments were amended with Ni and placed within either a streamside mesocosm or deployed in situ. DGT-measured Ni concentrations (CDGT) increased with increasing total Ni, were greater at depth, and decreased over time. Relationships between Ni C DGT and sediment geochemistry indicated a shift in Ni partitioning from AVS-bound to Fe- and Mn-associated Ni. In both experiments, DGT-measured Ni poorly predicted the invertebrate response to metal, whereas models that included total Ni or (SEMNi-AVS)/fOC effectively predicted the invertebrate response for the streamside mesocosm and in situ experiments, respectively. CDGT overestimated the available Ni fraction, possibly due to sampling either nonbioavailable solid-phase Ni or Ni irrespective of cations competing at the biotic ligand. We suggest that CDGT cannot replace (SEMNi-AVS)/fOC for predicting invertebrate response to sediment Ni, and greater understanding of metal species lability to DGTs is needed before assuming equivalence between bioavailable and DGT-labile metals in sediments. © 2012 American Chemical Society. Source


Burton Jr. G.A.,University of Michigan | Rosen G.,Space and Naval Warfare Systems Center Pacific | Chadwick D.B.,Space and Naval Warfare Systems Center Pacific | Greenberg M.S.,U.S. Environmental Protection Agency | And 3 more authors.
Environmental Pollution | Year: 2012

In situ-based testing using aquatic organisms has been widely reported, but is often limited in scope and practical usefulness in making decisions on ecological risk and remediation. To provide this capability, an integrated deployment system, the Sediment Ecotoxicity Assessment (SEA) Ring was developed, which incorporates rapid in situ hydrological, chemical, bioaccumulation, and toxicological Lines-of-Evidence (LoE) for assessing sediment and overlying water contamination. The SEA Ring system allows for diver-assisted, or diverless, deployment of multiple species of ecologically relevant and indigenous organisms in three different exposures (overlying water, sediment-water interface, and bulk sediment) for periods ranging from two days to three weeks, in a range of water systems. Measured endpoints were both sublethal and lethal effects as well as bioaccumulation. In addition, integrated passive sampling devices for detecting nonpolar organics (solid phase micro-extraction fibers) and metals (diffusive gradients in thin films) provided gradient measures in overlying waters and surficial sediments. © 2011 Elsevier Ltd. All rights reserved. Source


McDonald C.P.,Michigan Technological University | Urban N.R.,Michigan Technological University | Barkach J.H.,Great Lakes Environmental Center | McCauley D.,Great Lakes Environmental Center
Journal of Soils and Sediments | Year: 2010

Purpose: The sediments of Torch Lake, located in Houghton County, MI, USA, have been impacted by copper mining activity. Remediation of the site has focused on immobilizing shoreline tailing deposits. However, a large amount of copper remains in the mining-sourced sediment, and high copper concentrations persist in surface sediments. This study analyzes sediment core and sediment trap data to determine the source of copper in the surface sediments. Materials and methods: Sediment cores were retrieved from the lake, sectioned into 0. 5-cm to 1. 0-cm slices, and analyzed for Cu (atomic absorption spectrophotometry), bulk density, and organic matter content (loss on ignition). Sedimentation rates were determined using radioisotope dating. Sediment traps were deployed throughout the lake, and the collected material was analyzed for Cu and other metals (ICP-MS). Results and discussion: Radioisotope- and sediment trap-derived sedimentation rates agree well. Copper concentrations in the post-mining sediment are significantly (approximately 1. 5 to 2 times) greater than those in the underlying mine tailings. Current copper deposition rates, calculated from sediment trap data, are lower (∼1. 5 to 2 times) than accumulation rates measured in the surface sediment of the cores. Conclusions: Physical sediment properties and copper concentrations indicate the shoreline tailings piles are probably not a significant source of copper to the post-mining sediment, suggesting the excess copper is originating either in the water column or in the underlying tailings. Copper deposition rates measured in the sediment traps suggest a combination of these mechanisms. © Springer-Verlag 2010. Source


Soucek D.J.,Illinois Natural History Survey | Linton T.K.,Great Lakes Environmental Center | Tarr C.D.,Great Lakes Environmental Center | Dickinson A.,Illinois Natural History Survey | And 3 more authors.
Environmental Toxicology and Chemistry | Year: 2011

Total dissolved solids (TDS) represent the sum of all common ions (e.g., Na, K, Ca, Mg, chloride, sulfate, and bicarbonate) in freshwater. Currently, no federal water quality criteria exist for the protection of aquatic life for TDS, but because the constituents that constitute TDS are variable, the development of aquatic life criteria for specific ions is more practical than development of aquatic life criteria for TDS. Chloride is one such ion for which aquatic life criteria exist; however, the current aquatic life criteria dataset for chloride is more than 20 years old. Therefore, additional toxicity tests were conducted in the current study to confirm the acute toxicity of chloride to several potentially sensitive invertebrates: water flea (Ceriodaphnia dubia), fingernail clams (Sphaerium simile and Musculium transversum), snail (Gyraulus parvus), and worm (Tubifex tubifex), and determine the extent to which hardness and sulfate modify chloride toxicity. The results indicated a significant ameliorating effect of water hardness (calcium and magnesium) on chloride toxicity for all species tested except the snail; for example, the 48-h chloride median lethal concentration (LC50) for C. dubia at 50mg/L hardness (977mg Cl-/L) was half that at 800mg/L hardness (1,836mg Cl-/L). Conversely, sulfate over the range of 25 to 600mg/L exerted a negligible effect on chloride toxicity to C. dubia. Rank order of LC50 values for chloride at a given water hardness was in the order (lowest to highest): S. simile Source

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