Whole-Life-Stage Characterization in the Basic Biology of <i>Daphnia magna</i> and Effects of TDCIPP on Growth, Reproduction, Survival, and Transcription of Genes

Toxicity tests of chemicals have mainly focused on the partial life-cycle evaluation of model animals. Limited information is available for the evaluation of effects of chemicals from a whole-life-stage exposure perspective. The objective of this study was to perform a whole-life-stage characterization in the basic biology of <i>Daphnia magna</i> (<i>D. magna</i>) and evaluate the effects of a known organophosphate ester (OPE) contaminant, tris­(1,3-dichloro-2-propyl) phosphate (TDCIPP), on growth, reproduction, survival, and transcription of genes. The whole-life-stage characterization in growth, reproduction, and survival of <i>D. magna</i> was conducted, and representative sampling time points for the three developmental stages were identified (day 6, day 32, and day 62). Transcriptomic profiles for these three stages were compared, and stage-specific PCR arrays of <i>D. magna</i> were developed. The whole-life-stage exposure to environmentally relevant or greater concentrations of TDCIPP significantly inhibited growth and reproduction of <i>D. magna</i> and decreased survival at the later stage of the exposure experiment (≥32 days). Such adverse effects were not observed in the early stage of the exposure (