DSpace
 
  Repositório Institucional da Universidade de Aveiro > Departamento de Biologia > BIO - Artigos >
 Life-history responses of Daphnia magna Straus to binary mixtures of toxic substances: Pharmacological versus ecotoxicological modes of action
Please use this identifier to cite or link to this item http://hdl.handle.net/10773/5353

title: Life-history responses of Daphnia magna Straus to binary mixtures of toxic substances: Pharmacological versus ecotoxicological modes of action
authors: Barata, Carlos
Baird, Donald J.
Nogueira, António J. A.
Agra, Ana Raquel
Soares, Amadeu M. V. M.
keywords: Mixture toxicity
Mode of action
Metals
Insecticides
Pyrethroids
Daphnia
Feeding
issue date: 2007
publisher: Elsevier
abstract: Two prevailing theoretical models: concentration addition (CA) and independent action (IA), predict mixture toxicity on the basis of known toxicities of the mixture components. To date, both models have been in most occasions evaluated using unicellular in vivo responses or biochemical in vitro responses. However, when considering more complex models such as the whole organism physiology or life-history traits, the dominant ecotoxicological mode of action, based on the exposure concentrations at which various toxicological effects become operative at the level of whole organism, should be considered. Offspring production in Daphnia magna is driven by the resources acquired from food, and the number of live offspring produced by an organism is the result of two independent factors: the number of eggs produced and the percentage of eggs that survive egg development. In this study joint toxicity effects on offspring production in D. magna were tested using binary mixtures of toxic contaminants known to specifically impair food acquisition (lambda-cyhalothrin and cadmium) or to cause egg mortality during development (3,4 dichloroaniline). Tests were performed using a simplified 10-day reproduction assay initiated with gravid females. The results obtained indicate that irrespective of their primary pharmacological mode of action, the joint toxicity of cadmium and X-cyhalothrin was predicted by the CA model, whereas the joint toxicity of cadmium and 3,4 dichloroaniline was predicted by the IA model. Thus, the results obtained indicate that for life-history traits such as reproduction responses, the dominant ecotoxicological rather than the pharmacological mode of action should be used for predicting joint mixture effects. (c) 2007 Elsevier B.V. All rights reserved.
URI: http://hdl.handle.net/10773/5353
ISSN: 0166-445X
publisher version/DOI: http://dx.doi.org/10.1016/j.aquatox.2007.07.004
source: Aquatic Toxicology
appears in collectionsCESAM - Artigos
BIO - Artigos

files in this item

file description sizeformat
140_AquaToxico_2007_84_439.pdf634.9 kBAdobe PDFview/open
Restrict Access. You can Request a copy!
statistics

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

 

Valid XHTML 1.0! RCAAP OpenAIRE DeGóis
ria-repositorio@ua.pt - Copyright ©   Universidade de Aveiro - RIA Statistics - Powered by MIT's DSpace software, Version 1.6.2