Ecotoxicity - Daphnia magna: Reproduction Test (OECD 211: 1998).

            This test aims to evaluate the effects of chemical products on the reproduction of Daphnia magna. For this, young Daphnia females less than 24 hours old at the beginning of the test are exposed to the test product added to the water in a range of concentrations. The duration of the test is 21 days. At the end of the test, the total number of pups produced by each adult is evaluated. For this purpose, the offspring produced by adults who die during the test must be excluded from the calculations.

            The reproduction of the animals can be expressed in several ways (e.g. number of live young produced by each animal per day from the first day) but this must be informed in addition to the total number of new offspring produced by each living adult at the end of the test. The reproductive capacity of the animals exposed to the tested product is compared with that of the controls to determine the minimum concentration with effect (LOEC: Lowest Observed Effect Concentration) and likewise the concentration without effect (NOEC: No Observed Effect Concentration). In addition, if possible, the data is analyzed using a regression model to estimate the concentration that would cause a certain percentage reduction in reproductive capacity, ie the EC (e.g. EC50, EC20 or EC10). The survival of the parental animals and the period until the appearance of the first offspring should also be reported. Other effects on parameters such as growth (e.g. size) can also be examined.

            Information on the results of the acute immobilization test (OECD Standard 202: Daphnia spp. Acute Immobilization Test) should be available with Daphnia magna. This result may be useful to select an appropriate range of concentrations in breeding tests. Likewise, the solubility of the test product must be known and an analytical method must be available to quantify the concentration of the product in the test solution. It is convenient to have the structural formula, purity of the substance, stability to light, stability in the test conditions, pKa, POW and results of biodegradability tests.