Sediments contaminated

These observations contrast with some of the results obtained in natural waters. In the experiments where contaminated sediments were equilibrated with Lake Michigan water for a number of days, the Pu(IV) that was on the sediments and was transferred to the water was oxidized to Pu(V), with the oxidation occurring either during or after desorption (15). The studies in the Irish Sea near Windscale show that although no more than 1 percent of the waste effluent stream is oxidized plutonium, approximately 5 percent of the plutonium released leaves the area in the currents of the Irish Sea as oxidized plutonium. Most of the plutonium, therefore, must be oxidized fairly rapidly in sea water. 

PCBs have been implicated in the decline of certain populations of fish-eating birds, for example, in the Great Lakes of North America. Although their use is now banned in most countries and very little is released into the environment as a consequence of human activity, considerable quantities remain in sinks (e.g., contaminated sediments and landfill sites), from which they are slowly redistributed to other compartments of the environment. There continues to be evidence that PCB residues are still having environmental effects, for example, on birds and fish. 

A wide range of azaarenes including acridines and benzacridines, 4-azafluorene, and 10-azabenzo[fl]pyrene (Figure 1.32) has been identified in particulate samples of urban air, and some of them have been recovered from contaminated sediments (Yamauchi and Handa 1987). 

Bacteria isolated from marine macrofaunal burrow sediments and assigned to Lutibac-terium anuloederans were able to degrade phenanthrene in a heavily contaminated sediment (Chung and King 2001). 

Experiments examined a chlorocatechol-contaminated sediment, and interstitial water prepared from it. These showed that the concentrations of total 3,4,5-tri- and tetrachloro-catechols (i.e., including the fraction that is released only after alkaline extraction) were apparently unaltered during prolonged incubation even after addition of cnltnres with established dechlorinating capability for the soluble chlorocatechols (Allard et al. 1994). 

Allard A-S, P-A Hynning, M Remberger, AH Neilson (1994) Bioavailability of chlorocatechols in naturally contaminated sediment samples and of chloroguaiacols covalently bound to Cj-guaiacyl residues. Appl Environ Microbiol 60 777-784. 

Herbes SE, LR Schwall (1978) Microbial transformation of polycyclic aromatic hydrocarbons in pristine and petroleum-contaminated sediments. Appl Environ Microbiol 35 306-316. 

Because of the difficulty in obtaining pure cultures of anaerobic bacteria, use has been made of anaerobic sediment slurries in laboratory experiments. In some of these, although no enrichment was deliberately incorporated, experiments were carried out over long periods of time in the presence of contaminated sediments and adaptation of the natural flora to the xenobiotic during exposure in the laboratory might therefore have taken place. The design of these experiments may also inevitably result in interpretative difficulties. A few illustrations are provided ... 

Wu Q, DL Bedard, J Wiegel (1999) 2,6-dibromobiphenyl primes extensive dechlorination of Arochlor 1260 in contaminated sediment at 8-30°C by stimulating growth of PCB-dehalogenating microorganisms. 

Bushart SP, B Bush, EL Barnard, A Bott (1998) Volatilization of extensively dechlorinated polychlorinated biphenyls from historically contaminated sediments. Environ Toxicol Chem 17 1927-1933. 

Jeon CO, W Park, P Padmanabhan, C Derito, JR Snape, EL Madsen (2003) Discovery of a bacterium, with distinctive dioxygenase, that is responsible for in situ biodegradation in contaminated sediment. Proc Natl Acad Sci USA 100 13591-13596. 

Hughes JB, DM Beckles, SD Chandra, CH Ward (1997) Utilization of bioremediation processes for the treatment of PAH-contaminated sediments. J IndMicrobiol Biotechnol 18 152-160. 

Magar VS, GW Johnson, RFC Brenner, JF Quensen, EA Foote, G Durell, JA Ickes, C Peven-Mccarthy (2005a) Long-term recovery of PCB-contaminated sediments at the Lake Hartwell superfund site PCB dechlorination. 1. End-member characterization. Environ Sci Technol 39 3538-3547. 

Chlorinated anilines are produced by the reduction of PCNB that is used as a fungicide against a variety of commercial crops. The transformation of PCNB has been examined with a methanogenic enrichment culture from contaminated sediment, although this contained neither PCNB nor its reduction product pentachloroaniline (PCNA). The culture not only reduced the initial PCNB, but also carried out sequential dechlorination to tetra-, tri-, dichloroanilines, and ultimately to 3- and 4-chloroaniline (Tas and Pavlostathis 2005). 

Use of Sediment Quality Guidelines and Related Tools for the Assessment of Contaminated Sediments Wenning, Batley, Ingersoll, Moore, editors... 

Klemm W, Baumeach G (1995) Trace element determination in contaminated sediments and soils by ultrasonic slurry sampling and Zeeman graphite furnace atomic absorption spectrometry. Fresenius J Anal Chem 353 12-15. 

Various technologies such as dikes, covers, and in situ grouting can be used for the control of migration of contaminants from contaminated sediments or for prevention of contamination of clean sediments. 

Retaining dikes and berms. Retaining dikes and berms include earthen embankments, earth-filled cellular and double-sheet pile walls, water inflated dams, and so on, which aim to minimize the transport of contaminated sediments. 

Cover methods. Cover methods are used to cover contaminated sediments in order to minimize leaching of contaminants and prevent erosive transport of contaminated sediments. 

In situ grouting. The in situ grouting method involves injecting grouting materials into sediments to stabilize the contaminated sediments. In situ containments can be either temporary or permanent. However, permanent containment of contaminated sediments has not been well demonstrated or widely used. 

Army. 1994. Development of a chronic sublethal bioassay for evaluating contaminated sediment with the marine polychaete worm Nereis (Neanthes) arenaceodentata. Vicksburg, MS U.S. Army Corps of Engineers, Waterways Experiment Station Environmental Laboratory. Miscellaneous Paper D-94-5. 

BL and Ames assays for screening of contaminated sediment a comparison... 

The isomeric profile of HBCD found in contaminated sediment samples from Monzon was similar to that of commercial HBCD formulations, with y-HBCD being the most abundant isomer (between 94 and 99% contribution to the total HBCD). The same findings were observed in sediments from lake Winnipeg, where HBCD contamination was dominated by y-isomer [4]. 

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