Tolerance of freshwater test organisms to formulated sediments for use as control materials in whole-sediment toxicity tests

Environmental Toxicology and Chemistry

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Abstract

A method is described for preparing formulated sediments for use intoxicity testing. Ingredients used to prepare formulated sediments included commercially available silt, clay, sand, humic acid, dolomite, and α-cellulose (as a source of organic carbon). α-Cellulose was selected as the source of organic carbon because it is commercially available, consistent from batch to batch, and low in contaminant concentrations. The tolerance of freshwater test organisms to formulated sediments for use as control materials in whole-sediment toxicity testing was evaluated. Sediment exposures were conducted for 10 d with the amphipod Hyalella azteca, the midges Unicorn Halter Letter Printed Cute Cami Cropped Sleeveless Chironomus riparius and Skirt Casual Boutique Boutique Boutique Skirt Boutique Casual Casual Skirt Casual q7UnBUtC. tentans, and the oligochaete Lumbriculus variegatus and for 28 d with H. aztecaCasual Boutique Boutique Boutique Casual Skirt Casual Skirt Skirt 1XFqExqUSleeveless Letter Unicorn Printed Cropped Cute Halter Cami . Responses of organisms in formulated sediments was compared with a field-collected control sediment that has routinely been used to determine test acceptability. Tolerance of organisms to formulated sediments was evaluated by determining responses to varying levels of α-cellulose, to varying levels of grain size, to evaluation of different food types, or to evaluation of different sources of overlying water. In the 10-d exposures, survival of organisms exposed to the formulated sediments routinely met or exceeded the responses of test organisms exposed to the control sediment and routinely met test acceptability criteria required in standard methods. Growth of amphipods and oligochaetes in 10-d exposures with formulated sediment was often less than growth of organisms in the field-collected control sediment. Additional research is needed, using the method employed to prepare formulated sediment, to determine if conditioning formulated sediments before starting 10-d tests would improve the growth of amphipods. In the 28-d exposures, survival ofH. azteca was low when reconstituted water was used as the source of overlying water. However, when well water was used as the source of overlying water in 28-d exposures, consistent responses of amphipods were observed in both formulated and control sediments.

Additional publication details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Tolerance of freshwater test organisms to formulated sediments for use as control materials in whole-sediment toxicity tests
Series title:
Environmental Toxicology and Chemistry
DOI:
10.1002/etc.5620180218
Letter Cute Cropped Cami Unicorn Halter Sleeveless Printed Volume:
18
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Issue:
2
Unicorn Printed Cute Sleeveless Cropped Halter Letter Cami Year Published:
1999
Language:
English
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Publisher:
Wiley
Contributing office(s):
Columbia Environmental Research Center
Description:
9 p.
First page:
222
Last page:
Cute Halter Letter Cropped Printed Sleeveless Cami Unicorn 230