The Role of Particulate Matter in the Movement of Contaminants in the Great Lakes

Abstract

Particle-contaminantinteractions and subsequent behavior of the particulate matter control the long-term concentration of many compounds in aquatic systems. Even in deep systems such as the Great Lakes, particle settling times from the water column are less than 1 year. After reaching the bottom, contaminant-laden particles are redistributed by episodic cycles of resuspension and redeposition, resulting in focusing, which is the spatially inhomogeneous distribution of contaminants in sediments. Bioturbation, coupled with focusing, provides source material to the resuspendible pool. The combination of these processes mediates both the composition and long-term behavior of contaminants in these lakes.IN THE GREAT LAKES, AS IN MANY AQUATIC SYSTEMS, the movement of particulate matter plays a crucial role in determining the levels and fate of most contaminants. Persistent hydrophobic contaminants have a strong affinity for particles. As a result, the process of sorption and settling into the sediments is generally a major removal mechanism. This mechanism is very important in large systems such as the Great Lakes, where hydraulic residence times are long (3-190 years), and particle residence times in the water column are generally much less than 1 year. Thus, contaminants with a high degree of affinity for settling particles can be very efficiently scavenged from the system. However, studies of the long-term behavior of certain fallout radionuclides and stable contaminants (J, 2) have shown that higher levels persist in the lakes than This chapter not subject to U.S.

Juvenile Sea Bass Liver Biotransformation and Erythrocytic Genotoxic Responses to Pulp Mill Contaminants

“…Since retene is formed by anaerobic microbial biotransformation of RAs (Tavendale et al, 1997a,b), these pulp mill e%uent constituents will be available for reintroduction into the water column through a resuspension process (Eadie and Robins, 1987). Furthermore, the half-life of sediment RAs was estimated to be 30 years (Suthridge and Tavendale, 1996).…”

Winter-Spring Storms and Their Influence on Sediment Resuspension, Transport, and Accumulation Patterns in Southern Lake Michigan

“…The long hydraulic residence time of Lake Michigan (τ ≈ 100 y), coupled with rapid sorption and settling of particleassociated constituents, ultimately results in large inventories of nutrients and trace contaminants in sediments (Eadie and Robbins, 1987;Bogden et al, 2002;Hornbuckle et al, 2004 (Edgington and Robbins, 1976;Eadie and Robbins, 1987;Robbins and Eadie, 1991). Although Eadie et al, 2002;Ji et al, 2002;Vanderploeg et al, 2007).…”

“…It was hypothesized that materials residing in resuspendible pools were biogeochemically transformed within the lake, then redistributed primarily during the thermally unstratified period by a spectrum of energetic events (Chambers and Eadie, 1981;Eadie et al, 1984;Mortimer, 1988;Lesht, 1989;Eadie et al, 1996;Beletsky et al, 2003;Cardenas et al, 2005;Schwab et al, 2006). In the fol- resuspension from external inputs (Eadie et al, 1984(Eadie et al, , 1989Eadie and Robbins, 1987;Robbins and Eadie, 1991). December had the highest number of days with SLMTI exceeding 10 mg l -1 , but the days for which SLMTI exceeded 25 mg l -1 were more uniformly distributed among January, March, November, and December.…”

Regeneration, recycling, and trophic transfer of trace metals by microbial food‐web organisms in the pelagic surface waters of Lake Erie

“…Various inorganic surfaces, such as calcite, clays, and iron and manganese oxyhydroxides, may be involved in scavenging, but in the pelagic environment, biological surfaces are considered to dominate scavenging processes (Sigg 1994;Murray 1987;Morel and Hudson 1985). This is particularly true in the pelagic surface waters of the Laurentian Great Lakes of North America, which are effectively isolated from sediment influences during thermal stratification (Eadie and Robbins 1987).Among the biological particles, picoplankton (bacteria, cyanobacteria, and algae; 0.2-2 pm) are ideally suited to the scavenging of trace metals (Fisher 1985) owing to their rapid growth rates and high surface area-to-volume ratios. …”