Toxicity whole sediment

TIF TU TUdw U.S. ACE U.S. EPA WAPT WS WT Toxicity Incremental Factor Toxic Unit Toxic Unit expressed on a dry weight basis United States Army Corps of Engineers United States Environmental Protection Agency Weighed Average of Phase Toxicity Whole Sediment Wet Sediment. 

US EPA (1996) Whole sediment acute toxicity invertebrates, freshwater. OPPTS 850.1735. US EPA, Washington DC... 

Weston DP, You J, Harwood AD et al (2009) Whole sediment toxicity identification evaluation tools for pyrethroid insecticides in. Temperature manipulation. Environ Toxicol Chem 28 173-180... 

Cleveland, L. Little, E.E. Petty, J.D. Johnson, B.T. Lebo, J.A. Orazio, C.E. Dionne. J. Crockett, A. 1997, Toxicological and chemical screening of Antarctica sediments Use of whole sediment toxicity tests, Microtox, Mutatox, and semipermeable membrane devices (SPMDs). Mar. Pollut. Bull 34 194-202. 

Day, C. Dutka, B.J. Kwan, K.K. Batista, N. Reynoldson, T.B. Metcalfe-Smith, J.L. Correlations between sohd-phase microbial screening assays, whole-sediment toxicity tests with macroinvertebrates and in situ benthic community structure. J. Great Lakes Res. 1995, 21, 192-206. 

Several phases associated with sediments are evaluated for their toxic potential as Tables 10 and 11 indicate. Whole sediment and pore water stand out as phases that are most frequently investigated (Tab. 13). Because sediments act as contaminant... 

Cote, C., Blaise, C., Michaud, J.-R., Menard, L., Trottier, S., Gagne, F. and Lifshitz, R. (1998a) Comparisons between microscale and whole-sediment assays for freshwater sediment toxicity assessment, Environmental Toxicology and Water Quality 13 (1), 93-110. 

Day, K.E., Kirby, R.S. and Reynoldson, T. B. (1995b) The effect of manipulations of freshwater sediments on responses of benthic invertebrates in whole-sediment toxicity tests, Environmental Toxicology and Chemistry 14 (8), 1333-1343. 

Kemble, N.E., Dwyer, F.J., Ingersoll, C.G., Dawson, T.D. and Norberg-King, T.J. (1999) Tolerance of freshwater test organisms to formulated sediments for use as control materials in whole-sediment toxicity tests, Environmental Toxicology and Chemistry 18 (2), 222-230. 

Suedel, B.C. and Rodgers Jr, J.H. (1996) Toxicity of fluoranthene to Daphnia magna, Hyalella azteca, Chironomus tentans, and Stylaria lacustris in water-only and whole sediment exposures, Bulletin of Environmental Contamination and Toxicology 57 (1), 132-138. 

Hoss, S. and Krebs, F. (2003) Dilution of toxic sediments with unpolluted artificial and natural sediment - Effects on Caenorhabditis elegans (Nematoda) in a whole sediment bioassay -Proceedings 13th Annual meeting, Society of Environmental Toxicology and Chemistry - Europe Branch (SETAC-Europe), 28.04 -01.05. 2003, Hamburg, pp. 148. 

U.S. EPA (US Environmental Protection Agency) (2003) DRAFT. Porewater and whole sediment toxicity identification evaluation for freshwater and marine sediments Phase I (Characterization), Phase II (Identification) and Phase III (Confirmation) modifications of effluent procedures. Office of Research and Development, Narragansett, RI and Duluth, MN. 

It offers the possibility of incorporating any bioassay that is currently available. It thus provides the current best estimate of relative hazard for the sites being investigated. There is however a continuing need to develop, both for freshwater and marine or estuarine ecosystems, a battery of validated toxicity tests with sensitive species for whole sediment, wet sediment, organic extract, and pore water. 

The first study was designed to assess the suitability of various microscale bioassays and recommend an appropriate testing strategy for sediment toxicity assessment (Cote et al., 1998a,b). The recommended test batteries included seven micro-scale laboratory assays conducted on bacteria (Vibrio fischeri), cnidarians (Hydra attenuata), micro-crustaceans (Thamnocephalus platyurus), and benthic macroinvertebrates (Hyalella azteca and Chironomus riparius), and involved two phases of exposure (pore water and whole sediment). A total of 16 stations were included in the toxicity assessment scheme. 

The second study applied the weight-of-evidence approach to assess the quality of 17 sediment stations located in a highly industrialized sector along the St. Lawrence River. Five toxicity assays were conducted and encompassed four taxonomic groups, namely bacteria (V. fischeri and Escherichia coli), microphytes (Pseudokirchneriella subcapitata), amphipods (H. azteca) and chironomids (C. riparius), and considered three exposure phases (z. e., wet sediment, organic extract, and whole sediment). 

The general objective, principle, and scope of application of the pT-method are succinctly described in Section 1 and also reported elsewhere in this book (see Chapter 3 of this volume, Section 5.1), where readers will appreciate that this hazard assessment scheme is adaptable to both liquid and solid media. Briefly recalled here in the context of solid-media samples such as dredged material, the pT-value, which relates to a single bioassay, and the pT-index, derived from the most sensitive organism in a test battery, permit a numerical classification of environmental samples on the basis of ecotoxicological principles. Sediment from any aquatic ecosystem (freshwater, brackish, marine) and from any of its phases (whole sediment, porewaters, elutriates or organic extracts) can be appraised provided that the proper standardized toxicity tests are available. There are whole-sediment test protocols standardized for many agencies (e.g., Environment Canada, ASTM). 

In the case of whole-sediment toxicity determination, the necessary dilutions can be made with reference sediment material. A standardized method whereby polluted sediments can be diluted with unpolluted sediments for sediment-contact tests is currently being researched (Hoss and Krebs, 2003). Hence, the pT-method is capable of capturing the toxic effects of both soluble and adsorbed contaminants in a given sample, assuming that appropriate toxicity tests (i.e., solid-phase contact tests on whole sediment and tests on porewater or elutriates) are used. 

Appraising the toxic potential of biologically available contaminants in sediment should include three compartments the whole sediment (with standardized direct contact assays when these are available), the porewater, and the elutriate (aqueous extract). Additional hazard information can also be obtained from toxicity testing conducted on organic extracts using methanol or acetone. 

The sample dilution principle employed in the pT-scale improves the determination of toxic hazard potentials of sediment samples over that of effect percentages reported for undiluted test samples. For instance, a 100% effect measured with a specific endpoint and produced by undiluted samples may become undetectable after a dilution of 1 2 or after much higher dilutions. Clearly, it is essential to know the dilution level at which a whole sediment (or one of its liquid phases) ceases to be toxic1. In this respect, the pT-dilution approach offers valuable information allowing sediments to be more accurately classified in terms of the magnitude of toxicity. 

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