DDT-Related Compounds Bound to the Nonextractable Particulate Matter in Sediments of the Teltow Canal, Germany

Abstract

Sediment samples of the Teltow Canal (Berlin, Germany) were analyzed with respect to extractable and nonextractable organic compounds. The study focused on the identification and quantitation of bound 2,2-bis(chlorophenyl)-1,1,1-trichlorethane (DDT) residues in order to obtain further information about the fate of DDT-derived compounds within the particulate matter of the aquatic environment. Various chemical degradation techniques and a complementary online pyrolysis-GC/MS method were applied to the pre-extracted sediment residues. Generally, the distribution of the bound DDT-related compounds was found to differ distinctly from the substances distribution within the extractable fraction. The main metabolite of the anaerobic degradation pathway (2,2-bis(chlorophenyl)-1,1-dichlorethane, DDD) is most abundant in the sediment extracts but occurred only in insignificant concentrations in the degradation products of all procedures applied. The most abundant DDT-metabolites released after the degradation procedures were 4,4'-DBP, 4,4'-DDA, and 4,4'-DDM. In addition, 4,4'-DDM was detected at rather high concentrations by pyrolytic analysis. The results imply a weak association to the nonextractable particulate matter based on noncovalent interactions for the observed DDT-related contaminants. The release of these compounds was initiated by the modification and degradation of the organic macromolecular matrix as well as of the inorganic material. Furthermore, numerous methoxychlor-related compounds were detected not only in the extracts but also in parts of the hydrolysis products.

Isotopic constraints on the sources and associations of organic compounds in marine sediments

“…These included, freshwater sediments contaminated with BZTs from the Pawtuxet River (PR) (Reddy et al, 2000a) and from a control site (Station 3), upstream of the chemical plant that released the BZTs into the river ( Figure 5.2 insert), and freshwater sediments contaminated with DDT from Teltow Canal (TC) (Schwarzbauer et al, 2003). The Palos Verdes (PV) shelf is a coastal marine site that also has a history of DDT contamination (Eganhouse et al, 2000) and thus for comparison, sediments from this site were analyzed.…”

“…By examining the associations of organic compounds to MOM we aimed to make predictions regarding their long-term fate. In the case of hydrophobic organic contaminants (HOCs) this is of interest as previous studies have shown that certain HOCs or their metabolites can bind to MOM in sediments (Beller et al, 1998;Richnow et al, 1994;Reddy et al, 2000;Schwarzbauer et al, 2003), but this process is difficult to follow and quantitatively constrain. Binding to sedimentary MOM has the potential to influence the bioavalability, toxicity and transport of HOCs, and thus understanding these processes is of great interest from an environmental and human health perspective.…”

“…Once incorporated into sediments, HOCs are subject to varied and complex processes that confound our understanding of their ultimate fate. For example, laboratory (Richnow et al, 1997(Richnow et al, , 1998(Richnow et al, , 2000Hatcher et al, 1993) and field studies (Beller et al, 1998;Richnow et al, 1994;Reddy et al, 2000;Schwarzbauer et al, 2003) have shown that certain HOCs (or their metabolites) can bind to natural organic matter, but this process is not easy to follow and is especially difficult to quantify using current analytical approaches. These associations are, however, of interest as they can potentially affect the bioavailability, toxicity, transport and long-term fate of HOCs (Alexander, 1995).…”

“…Bound residue formation, however, has been proposed as a major sink for HOCs in soils and has been considered as a bioremediation strategy . Interactions between HOCs and OM have not been examined as extensively in aquatic sediments, but initial studies suggest that binding is a potentially important sink Richnow et al, 1994;Reddy et al, 2000a;Schwarzbauer et al, 2003). Aquatic sediments, however, provide a very different chemical and microbial environment to that found in soils and it is therefore of interest to determine whether the significance of binding in soils can be extrapolated to sediments.…”

Quantitation of Nonextractable Anthropogenic Quantitation of Nonextractable Anthropogenic Sediments after Chemical Degradation

“…The association of DDT-related pollutants to the nonextractable matter of sediments from the Teltow Canal has been reported recently [21]. This study was primarily initiated to quantify concentrations of bound 2,2-bis(chlorophenyl)-1,1,1-trichloroethane (DDT) residues in order to obtain further information about the fate of DDT-derived compounds within the particulate matter of the aquatic environment.…”