Uptake pathway for Ag bioaccumulation in three benthic invertebrates exposed to contaminated sediments

Marine Ecology Progress Series
By: , and 



We exposed 3 benthic invertebrates, the clam Macoma balthica, the polychaete Neanthes arenaceodentataand the amphipod Leptocheirus plumulosus, to Ag-contaminated sediments to evaluate the relative importance of various uptake routes (sediments, porewater or overlying water, and supplementary food) for Ag bioaccumulation. Silver bioaccumulation was evaluated at 4 levels of sediment Ag (0.1, 0,3, 1,2 and 3.3 µmol Ag g-1) and 2 levels of acid-volatile sulfide (AVS), <0.5 or ~40 µmol g-1, and compared among food treatments with or without Ag contamination, or with different food rations. L. plumulosus were incubated for 35 d in the Ag-contaminated sediments after 3 mo of Ag-sediment equilibration, and M. balthica and N. arenaceodentata for 19 d after 5 mo equilibration. Ag bioaccumulation in the 3 organisms was significantly correlated with 1N HCl-extractable Ag concentrations (Ag-SEM: simultaneously extracted Ag with AVS) in sediments. The Ag concentrations in porewater and overlying water were greatest in the sediments with least AVS, consistent with previous studies. Nevertheless, the amphipod and clam exposed to oxic sediments (<0.5 µmol AVS g-1) accumulated amounts of Ag similar to those accumulated by organisms exposed to anoxic sediments (~40 µmol AVS g-1), when Ag-SEM levels were comparable. The dissolved Ag source was important for bioaccumulation in the polychaete N. arenaceodentata. Amphipods fed Ag-contaminated food contained ~1.8-fold more tissue Ag concentrations than those fed uncontaminated food. As suggested in kinetic (DYMBAM) modeling studies, ingestion of contaminated sediments and food were the principle routes of Ag bioaccumulation by the benthic invertebrates during chronic exposure, but the relative importance of each uptake route differed among species.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Uptake pathway for Ag bioaccumulation in three benthic invertebrates exposed to contaminated sediments
Series title Marine Ecology Progress Series
DOI 10.3354/meps270141
Volume 270
Year Published 2004
Language English
Publisher Marine Ecology
Contributing office(s) Toxic Substances Hydrology Program
Description 12 p.
First page 141
Last page 152