title: Evaluation of the Daphnia magna reproduction test for detecting endocrine disruptors.
abstract: The Daphnia 21 d reproduction test is considered as a comprehensive and decisive test in the OECD Conceptual Framework for testing and assessment of endocrine disrupting chemicals (EDCs). However, how to interpret results of the Daphnia 21 d reproduction test for identification, risk assessment and testing strategy of EDCs remains an unsolved issue. This study analysed a total number of 135 published studies encompassing 86 known EDCs and non-EDCs with different modes of action. Our results show that the majority of effects on apical endpoints (survival, molting, growth, time to reproductive maturity, brood size, the number of broods, and the total number of offspring) do not seem to be EDC-specific. In contrast, the endpoint sex ratio is likely specific to juvenile hormones and their mimics. Variability is quantified for three most reported endpoints survival, the total number of offspring and sex ratio. Quantification of the endpoint sensitivity shows that the sensitivity of the sex ratio is lower than that of the total number of offspring. The Daphnia 21 d reproduction test gives insufficient information to conclude if a substance is an EDC or not. EDCs that are potent in assays in vitro may not be potent in the Daphnia 21 d reproduction test. We conclude that the Daphnia 21 d reproduction test is important for deriving No Observed Effect Concentrations for risk assessment but may produce false negatives in identification of EDCs when used on its own. A targeted testing strategy for selection of species, tests, and endpoints is suggested for identifying EDCs.
authors.affiliation: National Institute for Public Health and the Environment (RIVM), A. van Leeuwenhoeklaan 9, Bilthoven, The Netherlands. zhichao.dang@rivm.nl
authors.forename: ZhiChao
authors.initials: Z
authors.lastname: Dang
authors.forename: Yan
authors.initials: Y
authors.lastname: Cheng
authors.forename: Hui-ming
authors.initials: HM
authors.lastname: Chen
authors.forename: Yuan
authors.initials: Y
authors.lastname: Cui
authors.forename: Huan-huan
authors.initials: HH
authors.lastname: Yin
authors.forename: Theo
authors.initials: T
authors.lastname: Traas
authors.forename: Mark
authors.initials: M
authors.lastname: Montforts
authors.forename: Theo
authors.initials: T
authors.lastname: Vermeire
mesh_terms: D000818:Animals; D003621:Daphnia / Q000187:drug effects* / Q000502:physiology*; D004305:Dose-Response Relationship, Drug; D052244:Endocrine Disruptors / Q000032:analysis* / Q000633:toxicity*; D023381:Endpoint Determination; D005260:Female; D008297:Male; D012098:Reproduction / Q000187:drug effects; D018570:Risk Assessment
chemical_list: D052244:Endocrine Disruptors