Copper Sediment Toxicity and Partitioning during Oxidation in a Flow-Through Flume

• DOI: 10.1021/acs.est.5b00147
• Publication Date: 2015-05-12T16:46:12Z
• Authors: David M. Costello; Chad R. Hammersch...; G. Allen Burton
• Keywords: Hyalella azteca; Flume

The bioavailability of transition metals in sediments often depends on redox conditions the sediment. We explored how physicochemistry and toxicity anoxic Cu-amended changed as they aged (i.e., naturally oxidized) a flow-through flume. amended two (Dow Ocoee) with Cu, incubated flume, measured sediment over 213 days. As aged, oxygen penetrated to greater depth, relative abundance Fe oxides increased surface deep sediments, concentration acid volatile sulfide declined Ocoee sediments. total pool Cu did not change during aging, but porewater bound amorphous decreased while associated crystalline increased. dose–response epibenthic amphipod Hyalella azteca time, older being less toxic than freshly spiked observed strong relationship between H. growth across all sampling periods, measurable declines rates were at concentrations below interstitial water criteria established by U.S. EPA. Further, solid-phase models based AVS organic carbon overprotective poorly predicted suggest that quality for is best from measurement pore rather estimating bioavailable various ligands, which vary temporally spatially.