Quantitative structure-activity relationships and mixture-toxicity studies of alcohols and chlorohydrocarbons: reproducibility of effects on growth and reproduction of Daphnia magna

• Published in: Aquatic toxicology Vol. 12; no. 1; pp. 39 - 49
• Main Authors: De Wolf, W., Canton, J.H., Deneer, J.W., Wegman, R.C.C., Hermens, J.L.M.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 1988; Elsevier Science
• Subjects: Animal, plant and microbial ecology; Applied ecology; Biological and medical sciences; Complex mixture; Daphnia magna; Ecotoxicology, biological effects of pollution; Fresh water environment; Freshwater; Fundamental and applied biological sciences. Psychology; Growth; Reproducibility; Reproduction; Structure-activity relationship; Reproduction; Reproducibility; Growth; Complex mixture; Structure-activity relationship; Daphnia magna; Crustacea; Freshwater environment; Pollutant; Toxicity; Arthropoda; Cladocera; Invertebrata; Branchiopoda; Organic compounds
• ISSN: 0166-445X; 1879-1514
• DOI: 10.1016/0166-445X(88)90018-5

In subacute toxicity experiments for 10 nonreactive organic chemicals, such as alcohols and chlorobenzenes, the effects on growth and reproduction of Daphnia magna were studied. No-observed-effect concentrations (NOEC) for growth and reproduction were found to be approximately equal. For all compounds tested, these values and the median effective concentrations (EC 50) on reproduction correlated very well with hydrophobicity (octanol-water partition coefficient, P oct.) as shown by a quantitative structure-activity relationship (QSAR) study. From one of the QSAR equations, EC 50 values for 15 other compounds were predicted, after which the toxicity of mixtures of 10 and 25 compounds was tested. The toxicity was found to be predictable on the basis of concentration addition. Comparing the results of this study with those from earlier experiments, it may be concluded that subacute toxicity data for D. magna are very reproducible and are not very dependent upon the physical condition of the daphnids used.