Metals in aquatic systems

L., Dynamic speciation analysis and bioavailability of metals in aquatic systems, Environ Sci Technol,... 

Hudson, R. J. M. (1998). Modeling the fate of metals in aquatic systems the mechanistic basis of particle-water partitioning models, Crit. Rev. Anal. Chem., 28, 19-26. 

On the other hand, the presence of hydrophobic complexes is a prerequisite for partitioning and diffusion of metals into the lipid bilayer. In the following paragraphs, various types of metal complexes will be discussed, which are relevant to the interactions of metals in aquatic systems. The role of these various types of metal complexes with respect to interactions at the biological interphases will be systematically examined. 

The fate of heavy metals in aquatic systems depends on partitioning between soluble and partieulate solid phases. Adsorption, precipitation, coprecipitation, and complexation are processes that affect partitioning. These same processes, which are influenced by pH, redox potential, the ionic strength of the water, the concentration of complexing ions, and the metal concentration and type, affect the adsorption of heavy metals to soil (Richter and Theis 1980). 

Paquin PR, Santore RC, Farley K, Di Toro DM, Wu KB, Mooney KG, Winfield RP. 2003. Metals in aquatic systems a review of exposure, bioaccumulation, and toxicity models. Pensacola (FL) SETAC Press, 168 p. 

Honeyman, B.D., and Santschi, P.H. (1988) Critical review metals in aquatic systems. Predicting their scavenging residence times from laboratory data remains a challenge. Environ. Sci. Technol. 22, 862-871. 

Though several studies (5-9) have described the concentrations of trace elements in surface waters, most of them did not differentiate between species of a particular element. Some (10) have considered the distribution between dissolved and particulate forms. However, few attempts (11) have been made to evaluate the distribution of metals between various solid phase components of the suspended material. The present study provides quantitative estimates of dissolved (dissolved is defined as those aquatic components that could not be removed by centrifugation from liquid phase) and various solid phase associated metal fractions in southeastern United States streams. Between November 83 and August 85, 46 bi-weekly samples were taken from six SRP associated watersheds to determine dissolved (filterable) and total element concentrations. As one of several goals of the study was to assess the impact of natural and production related activities on trace element behavior in these aquatic systems, knowledge of speciation within solid and dissolved phases was essential for data interpretation. The research described herein used sequential extraction and a thermodynamics approach to define solid and dissolved phase species of Cu, Cd, Fe, Mn, Ni and Zn. The study also evaluated the effects of natural and production related processes on the distribution of metals in aquatic systems at SRP. 

Contaminated sediments are considered a large ecotoxicological risk to the aquatic environment (Burton, 1992). They may act as important sources or sinks of contaminants, e.g. trace metals, in aquatic systems (e.g. Gaillard et ah, 1986 Calmano et ah, 1993). As particle-water interactions influence the mobilization of trace metals in sediments (Hamilton-Taylor and Davison, 1995 Hong et al., 1995), (bio)availability... 

Tercier-Waeber ML, Taillefert M (2008) Remote in situ voltammetric techniques to characterize the biogeochemical cycling of trace metals in aquatic systems. J Environ Monit 10 30-54... 

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