Measuring and modelling mixture toxicity of imidacloprid and thiacloprid on Caenorhabditis elegans and Eisenia fetida
Gomez-Eyles, Jose L.; Svendsen, Claus; Lister, Lindsay; Martin, Heather; Hodson, Mark E.; Spurgeon, David J.. 2009 Measuring and modelling mixture toxicity of imidacloprid and thiacloprid on Caenorhabditis elegans and Eisenia fetida. Ecotoxicology and Environmental Safety, 72 (1). 71-79. 10.1016/j.ecoenv.2008.07.006Full text not available from this repository.
While the standard models of concentration addition and independent action predict overall toxicity of multicomponent mixtures reasonably, interactions may limit the predictive capability when a few compounds dominate a mixture. This study was conducted to test if statistically significant systematic deviations from concentration addition (i.e. synergism/antagonism, dose ratio- or dose level-dependency) occur when two taxonomically unrelated species, the earthworm Eisenia fetida and the nematode Caenorhabditis elegans were exposed to a full range of mixtures of the similar acting neonicotinoid pesticides imidacloprid and thiacloprid. The effect of the mixtures on C. elegans was described significantly better (p<0.01) by a dose level-dependent deviation from the concentration addition model than by the reference model alone, while the reference model description of the effects on E. fetida could not be significantly improved. These results highlight that deviations from concentration addition are possible even with similar acting compounds, but that the nature of such deviations are species dependent. For improving ecological risk assessment of simple mixtures, this implies that the concentration addition model may need to be used in a probabilistic context, rather than in its traditional deterministic manner.
|Programmes:||CEH Topics & Objectives 2009 onwards > Biogeochemistry > BGC Topic 3 - Managing Threats to Environment and Health|
|Additional Keywords:||Concentration addition, Synergism, Antagonism, Dose level dependence, Neonicotinoids, Piperonyl butoxide|
|NORA Subject Terms:||Biology and Microbiology
Ecology and Environment
|Date made live:||27 Feb 2009 10:16|
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