Sediment-bound metal

The solubility, mobility, and bioavailability of sediment-bound metals can be increased by four major factors in terrestrial and aquatic environments ... 

Griscom SB, Fisher NS and Luoma SN (2000) Geochemical influences on assimilation of sediment-bound metals in clams and mussels. Environ Sci Technol 34 91-99. 

Luoma, S.N. and E.A. Jenne. 1977. The availability of sediment-bound cobalt, silver, and zinc to a depositfeeding clam. Pages 213-230 in H. Drucker and R.E. Wildung (eds.). Biological Implications of Metals in the Environment. ERDA Symposium Series 42. Avail, as CONF-750929 from the Natl. Tech. Inform. Serv., Springfield, VA 22161. 

Luoma, S.N. and G.W. Bryan. 1979. Trace metal bioavailability modehng chemical and biological interactions of sediment-bound zinc. Pages 577-609 in E.A. Jenne (ed.). Chemical Modeling in Aqueous Systems. Amer. Chem. Soc., Sympos. Ser. 93, Washington, D.C. 

Metal bioavailability is generally increased with decreasing pH. This is due to the presence of phosphoric, sulfuric and carbonic acids, which increasingly solubilize organic- and particulate-bound metals. Particulate-bound metals are considered those bound to secondary minerals, for example, clays, iron and aluminum oxides, carbonates and sulfidic and phosphoric minerals. Due to the heterogeneous nature of soils and sediments, wide fluctuations in pH can exist in a given environment. For instance, metals may be more soluble in surface layers where plant exudates, microbial activity, moisture and leaching lower pH. 

Siripinyanond, A., Barnes, R. M., and Amarasiriwardena, D. (2002). Flow field-flow fractionation-inductively coupled plasma mass spectrometry for sediment bound trace metal characterization. J. Anal. At. Spectrom. 17(9), 1055-1064. 

Trace Metal Bioavailability Modeling Chemical and Biological Interactions of Sediment-Bound Zinc... 

Since the availability of Zn to bivalves varies among substrates, changes in the relative abundance of substrate concentrations should correlate with changes in the biological availability of the metal to organisms whose metal burden is controlled by sediments. The biological availability of sediment-bound Zn in this case is defined as the concentration of Zn in the bivalves relative to that in the sediment,... 

A fraction of the sediment bound phosphorus exists in a form which is not extracted with the hydrous metal oxides, but is removed by treatment with dilute hydrochloric acid. This suggests the occurrence of phosphorus in carbonate minerals and/or occurrence of phosphate minerals. 

Luoma, S.N. (1989) Can we determine the biological availability of sediment-bound trace metals Hydrobiologia, 176/177, 379-96,... 

As it is unlikely that the silicate-bound metals will leach from the soil or sediment, the use of aqua regia to give a pseudo-total analysis is perfectly acceptable in this situation. 

Ahlf, W., Calmano, W. Fdrstner, U. (1986) The effects of sediment-bound heavy metals on algae and importance of salinity. In Sediments and Water Interactions, ed. P.G. Sly, pp. 319-324. New York s Springer-Verlag. 

Sequential chemical extraction techniques are widely published in the literature and useful for determining the geochemical fractionation of metals in soils and sediments (27-29). Even though some methods may suffer from limitations (e.g., re-adsorption) the data are useful for assessing die conditions under which bound metal can be released from the soil. 

The analysis of metal partitioning indicated that for sediment V metals, including As, Cd, Cu, Pb, Mn, and Zn are associated to exchangeable + carbonate-bound fractions and Fe/Mn oxides-bound fraction in proportions ranging from 25% to 85% Ni and Cr are mainly associated to the residual fraction of the material. Sediment S showed a different metal partitioning Cd, Zn, and Pb are mainly (-60%) associated to exchangeable + carbonate-bound fractions and Fe/Mn oxides-... 

Respective differences of solubility were also observed for the reverse process. Steinberg (1987, Table 8.5) gives some empirically observed threshold values of pH beyond of which ammonium and bound metals were released from the sediments of an acidified soft-water lake. The specific capability of metals to be exchanged by H -ions and, thereby, released from the sediments into the water is explained by the different radius and charge of the metal ions. 

Heron G, Christensen TH (1995) Impact of sediment-bound iron on redox buffering in a landfill leachate polluted aquifer (Vejen, Denmark). Environ Sci Technol 29 187-192 Hunt CD, Smith DL (1983) Remobilization of metals from polluted marine sediments. Can J Fish Aquat Sci 40 132-142... 

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