Combined chemical (Fluoranthene) and drought effects on Lumbricus rubellus demonstrates the applicability of the independent action model for multiple stressor assessment
Long, Sara M.; Reichenberg, Fredrik; Lister, Lindsay J.; Hankard, Peter K.; Townsend, Joanna; Mayer, Philipp; Wright, Julian; Holmstrup, Martin; Svendsen, Claus; Spurgeon, David J.. 2009 Combined chemical (Fluoranthene) and drought effects on Lumbricus rubellus demonstrates the applicability of the independent action model for multiple stressor assessment. Environmental Toxicology and Chemistry, 28 (3). 629-636.Full text not available from this repository.
The combined effect of a chemical (fluoranthene) and a nonchemical stress (reduced soil moisture content) to the widely distributed earthworm Lumbricus rubellus were investigated in a laboratory study. Neither fluoranthene (up to 500 μg/g) nor low soil moisture (15% below optimal) had a significant effect on the survival of the exposed worms, but a significant effect on reproduction (cocoon production rate) was found for both stressors (p < 0.001 in both cases). The response of cocoon production to each stressor could be well described by a logistic model; this suggested that the joint effects may be applicable to description using the independent action (IA) model that is widely used in pharmacology and chemical mixture risk assessment . Fitting of the IA model provided a good description of the combined stressor data (accounting for 53.7% of total variation) and was the most parsimonious model describing joint effect (i.e., the description of the data was not improved by addition of further parameters accounting for synergism or antagonism). Thus, the independent action of the two responses was further supported by measurement of internal fluoranthene exposure. The chemical activity of fluoranthene in worm tissue was correlated only with soil fluoranthene concentration and not with soil moisture content. Taken together these results suggest that the IA model can help interpret the joint effects of chemical and nonchemical stressors. Such analyses should, however, be done with caution since the literature data set suggests that there may be cases where interactions between stressors result in joint effects that differ significantly from IA predictions.
|Programmes:||CEH Topics & Objectives 2009 onwards > Biogeochemistry > BGC Topic 1 - Monitoring and Interpretation of Biogeochemical and Climate Changes
CEH Topics & Objectives 2009 onwards > Biogeochemistry > BGC Topic 2 - Biogeochemistry and Climate System Processes
|Additional Keywords:||Drought, Polycyclic aromatic hydrocarbons, Multiple stressors, Independent action, Chemical activity|
|NORA Subject Terms:||Biology and Microbiology
Ecology and Environment
|Date made live:||27 Apr 2009 09:36|
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