Growth and reproduction of the cladoceran Ceriodaphnia dubia from a forested floodplain swamp

Longevity and Reproduction of Ceriodaphnia Dubia in Receiving Waters

Seven-day tests with Ceriodaphnia dubia are commonly used to estimate toxicity of effluents or receiving waters but can sometimes yield no toxicity outcomes even if pollutants are present. We conducted two sets of full life-cycle tests with C. dubia to (1) determine whether tests with longer exposure periods to low concentrations of contaminants in ambient water might reveal evidence of toxicit...

Effects of water chemistry on the chronic toxicity of lead to the cladoceran, Ceriodaphnia dubia.

As the first step toward parameterization of a chronic lead (Pb) biotic ligand model (BLM) for Ceriodaphnia dubia, 7-d toxicity tests were performed in waters modified to evaluate the influences of hardness, DOM (as Suwannee River NOM and Aldrich humic acid (HA)), pH (buffered with 4 mM MOPS) and alkalinity on the chronic toxicity of Pb. Calculated EC(20)s for the control base water test and ea...

Effects of metal and organophosphate mixtures on Ceriodaphnia dubia survival and reproduction.

The toxicity of mixtures of copper, zinc, and diazinon were determined for Ceriodaphnia dubia using 7-d survival and reproduction tests. Fifteen treatments, including combinations of the chemicals at 0, 25, 50, 75, and 100% of their individual median lethal concentrations, adding up to one toxic unit (TU) were tested. The TU was then used to classify each mixture response as additive, greater t...

Acute toxicity of thallium to Daphnia magna and Ceriodaphnia dubia.

Effects of Diet on Seven-Day Ceriodaphnia dubia Toxicity Tests

The purpose of this study was to evaluate the effects of four diets on the results of seven-day Ceriodaphnia dubia toxicity tests. Survival and reproduction were used as indices to detect the sensitivity of this species to acute and chronic copper stress. All toxicity tests were conducted using the moderately hard reconstituted water recommended in 1989 by the U.S. Environmental Protection Agen...