Reaction mass of 1-hydroxydecan-3-one and 3-(hydroxymethyl)nonan-2-one and nonan-2-one

Toxicity to aquatic algae and cyanobacteria

Description of key information

A study was performed to assess the toxicity of the substance to Pseudokirchneriella subcapitata under static conditions. The study was conducted in accordance with OECD Guideline 201 and following GLP. Initial target cell densities of 0.5E4 cells/mL were employed for the individual replicates and exposed for 72 hours to five concentrations of the substance (100, 50, 25, 12.5, 6.25 mg/L) and an untreated control. Six replicates were employed for the control and three for each test item concentration. The increase of cell numbers was assessed and where possible inhibition of growth was assessed by the determination of NOEC/LOEC and EC10, EC20, and EC50 for growth rate and yield after 72 hours. The measured initial concentrations of 3-(hydroxymethyl)nonan-2-one ranged from 74 % to 89 % of nominal. In the aged samples the measured concentrations were between 70 % and 89 % of nominal. Therefore, toxicological endpoints were evaluated using the mean measured concentrations (based on the geometric mean of the analytical recoveries for each concentration level) of the test item. The 72 h ErC50, ErC10, and NOEC values for algae are 25.0, 13.9, and 4.60 mg/L, respectively.

Key value for chemical safety assessment

EC50 for freshwater algae:

25 mg/L

EC10 or NOEC for freshwater algae:

13.9 mg/L