Reaction mass of melamine and Nickel, 5,5'-azobis-2,4,6(1H,3H,5H)-pyrimidinetrione complexes

Long-term toxicity to aquatic invertebrates

Description of key information

Daphnia Magna was exposed under semi-static conditions for 21 d to one concentration (10 mg/L) of the substance. No toxic effect was observed. A NOEC of >= 10 mg/L (nominal) (>26.2 µ/L, measured, geometric mean) was observed within 21 days related to reproduction and mortality.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

10 mg/L

Additional information

The given value was, NOEC >= 10 mg/L within 21 days related to reproduction and mortality.

In order to test long-term toxicity to invertebrates of the substance, the Daphnia were exposed to a limit test concentration of nominally 10 mg/L dissolved in dilution water and blank control solution for a period of 21 d under semi-static conditions. The test was performed according to the OECD Guideline 211 (Daphnia magna Reproduction Test). The criterion of adverse effects used in this study was the item-induced inhibitory effect on the parthenogenetic reproduction rate and the mobility behaviour/mortality rate of parent Daphnia, all effects being assessed at least three times a week. During the test a temperature range of 19.0 to 20.2°C was maintained in the test vessels, with a maximum temperature fluctuation of +/- 2 °C in each individual test. The temperature, the pH and the oxygen values were measured at the beginning and end of the test.

No toxic effects of the substance against daphnia were observed at a limit test concentration of 10 mg/L. The results are expressed in terms of nominal concentrations.

The content of the test item during the exposure period was verified by Ni- determination. Converted from nickel concentrations the concentration of the test item was in the range of 223 to 381 µg/L, the average within the exposure period of 21 d was 276 µg/L.