Published on the Web 8/21/2008.
Whole sediment toxicity identification evaluation tools for pyrethroid insecticides: III. Temperature manipulation†
Article first published online: 9 DEC 2009
Copyright © 2009 SETAC
Environmental Toxicology and Chemistry
Volume 28, Issue 1, pages 173–180, January 2009
How to Cite
Weston, D. P., You, J., Harwood, A. D. and Lydy, M. J. (2009), Whole sediment toxicity identification evaluation tools for pyrethroid insecticides: III. Temperature manipulation. Environmental Toxicology and Chemistry, 28: 173–180. doi: 10.1897/08-143.1
- Issue published online: 9 DEC 2009
- Article first published online: 9 DEC 2009
- Manuscript Accepted: 21 JUL 2008
- Manuscript Received: 27 MAR 2008
- Toxicity identification evaluation;
- Hyalella azteca;
- Sediment toxicity;
Since the toxicity of pyrethroid insecticides is known to increase at low temperatures, the use of temperature manipulation was explored as a whole-sediment toxicity identification evaluation (TIE) tool to help identify sediment samples in which pyrethroid insecticides are responsible for observed toxicity. The amphipod Hyalella azteca is commonly used for toxicity testing of sediments at a 23°C test temperature. However, a temperature reduction to 18°C doubled the toxicity of pyrethroids, and a further reduction to 13°C tripled their toxicity. A similar response, though less dramatic, was found for 1,1-bis(p-chlorophenyl)-2,2,2-trichloroethane (DDT), and dissimilar temperature responses were seen for cadmium and the insecticide chlorpyrifos. Tests with field-collected sediments containing pyrethroids and/or chlorpyrifos showed the expected thermal dependency in nearly all instances. The inverse relationship between temperature and toxicity provides a simple approach to help establish when pyrethroids are the principal toxicant in a sediment sample that could be used as a supplemental tool in concert with chemical analysis or other TIE manipulations. The phenomenon appears to be, in part, a consequence of a reduced ability to biotransform the toxic parent compound at cooler temperatures. The strong dependence of pyrethroid toxicity on temperature has important ramifications for predicting their environmental effects, and the standard test temperature of 23°C dramatically underestimates risk to resident fauna during the cooler months.