title: Mixture toxicity of three toxicants with similar and dissimilar modes of action to Daphnia magna.
abstract: Mixture toxicity of similar- and dissimilar-acting toxicants can be predicted by the models concentration addition (CA) and independent action (IA) using single substance toxicity data. Knowledge of the toxicants mode of action is thus required in order to use the models. In order to test the predictive capability of the models, we conducted Daphnia magna 48 h immobilization experiments with three toxicants with known modes of action (dimethoate, pirimicarb and linear alkyl benzene sulfonate) singly, and in binary and ternary mixtures. Our results indicate that CA and IA predict binary mixtures of similar- and dissimilar-acting toxicants equally well. CA and IA also equally predicted the ternary mixture consisting of both similar- and dissimilar-acting chemicals. The paper discusses the concept of mode of action and the implications the definition of mode of action has on the choice of reference model for mixture toxicity studies.
authors.affiliation: Department of Environmental, Social and Spatial Change, Roskilde University, Universitetsvej 1, 4000 Roskilde, Denmark.
authors.forename: Kristian
authors.initials: K
authors.lastname: Syberg
authors.forename: Anders
authors.initials: A
authors.lastname: Elleby
authors.forename: Henrik
authors.initials: H
authors.lastname: Pedersen
authors.forename: Nina
authors.initials: N
authors.lastname: Cedergreen
authors.forename: Valery E
authors.initials: VE
authors.lastname: Forbes
mesh_terms: D000821:Animal Feed; D000818:Animals; D002219:Carbamates / Q000633:toxicity; D000460:Chlorophyta; D003621:Daphnia / Q000187:drug effects*; D004117:Dimethoate / Q000633:toxicity; D007306:Insecticides / Q000633:toxicity*; D007928:Lethal Dose 50; D011237:Predictive Value of Tests; D011743:Pyrimidines / Q000633:toxicity
chemical_list: D002219:Carbamates; D007306:Insecticides; D011743:Pyrimidines; C011994:pirimicarb; D004117:Dimethoate