1-hydroxy-4-methyl-6-(2,4,4-trimethylpentyl)pyridin-2(1H)-one, compound with 2-aminoethanol (1:1)

Long-term toxicity to aquatic invertebrates

Description of key information

The Lowest Observed Effect Concentration (LOEC) and the No Observed Effect Concentration (NOEC) for the reproductive output as the most sensitive effect were determined directly from the results. The EC50-value for the adult mortality was calculated by sigmoidal dose-response regression. The EC50-value for the reproductive output was determined directly from the results. All effect values are given based on the geometric mean measured concentrations of the test item Octopirox.

      NOECReproduction       :       128 µg/L

      LOECReproduction       :       324 µg/L

      EC50, Reproduction       :       324 µg/L < EC50, Reproduction < 1255 µg/L

      EC50, Adult Mortality       :       324 µg/L (CI: 128 - 1255 µg/L)

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

128 µg/L

Additional information

Octopirox forms chelate complex with two and three valent ions like Fe(II), Fe(III), Al(III). If the test organism is dependent from such ions during the test e.g. algae, daphnia, this will influence growth and survival. As these ions mentioned before are ubiquitous in the sewer, the sewage treatment plant and in the environment e.g. river Octopirox forms immediately these chelate complexes. In order to avoid interference with the necessary test conditions in the Guideline tests and to avoid unrealistic test test settings e.g. pronounced toxicity by interference with essential ions, the aquatic ecotoxicity tests were carried out in river water where the ions mentioned above are present.