Reaction product with n-butanol of high-boiling stream resulting from the hydroxylation, oxidative cleavage and hydrolysis of vegetable oil saturated and unsaturated C16-C22 triglycerides.

Toxicity to aquatic algae and cyanobacteria

Description of key information

The key study available for algae was performed on FAV-ES itself (Muckle, 2014). The effect concentrations determined in that study were and EC50 (72h, growth rate) of > 5.2 mg/L (100 mg/L nominal) and an EC10 value (72h, growth rate) of > 5.2 mg/L (100 mg/L nominal) as well. The NOEC was determined at 1.8 mg/L (18 mg/L nominal).

Additional information

In total, 3 experiments were performed on FAV-ES. In the first experiment, the validity criteria were not met (mean coefficient of variation of daily growth rates was > 35 %). Therefore, the study was repeated. The results of the first experiment are not stated in this report, but will be kept together with the other raw data in the GLP archive of the test facility.

The second and third experiment were performed using five concentrations ranging from 10 to 100 mg/L nominal concentration. For sample preparation during the second experiment, a saturated solution was prepared for the test. This was done by mixing the sample weight 100.4 mg/L with the corresponding amount of nutrient medium (demineralised water enriched with minerals but without algae) and shaking vigorously for 24 hours. In the second experiment the treatments showed no significant inhibition of algal growth. At the beginning and at the end of the second experiment, the content of the test item in the test solutions was estimated using DOC-determination. Because of the very low solubility in test medium, no calculation from carbon content of the test item and DOC measurement was possible. The measured start concentration in the treatments was only slightly above the LOQ. At the end of the test, the concentration of DOC in the treatments and in the control was in the same range. The result from this study were consequently found to be not biologically meaningfull.

For sample preparation during the third experiment, the water-accommodated fractions for every treatment were prepared for the test. This was done by mixing the sample weight 100.2 / 56.2 / 32.8 / 19.0 and 10.1 mg/L with the corresponding amount of nutrient medium (demineralised water enriched with minerals but without algae) and shaking vigorously for 7 days ± 1 hour. This procedure can be stated as worst case scenario to achieve a doubtless maximum presence of dissolved test item. In the third experiment the treatments showed low but statistical significant inhibition of algal growth at nominal test item concentrations of 32 / 56 / 100 mg/L. At the beginning and at the end of the third experiment, the content of the test item in the test solutions was estimated using DOC-determination. A slightly increase in DOC concentration in accordance with the higher concentrated treatments could be observed. The determination of the results was based on the nominal concentrations and the calculated test item concentrations form the measured DOC concentrations of the third experiment and the content of organic carbon of the test item (73.39 %). Incubation time (test system Desmodesmus subspicatus) was 72 hours. The cell concentration of each replicate was determined by measuring the absorption of the solutions at 440 nm every 24 hours with a spectral photometer. The cell density of the cultures was calculated based on the correlation curve between the adsorption and the cell density of the cultures determined by microscope counts. Growth rate μ, area under the growth curve (AUC1) and the yield were determined from the cell densities at the respective observation times. The EC50s of potassium dichromate were tested in a separate reference test (201308R301). The values lay within the normal range of the laboratory. The following results for the test item FAV ES (FAV BUTILATO) were determined in the third experiment:

For growth rate, based on the on nominal concentrations, and between brackets measured concentrations:

- NOEC 18 mg/L (1.8 mg/L)

- LOEC 32 mg/L (2.8 mg/L)

- EC10 > 100 mg/L (> 5.2 mg/L)

- EC50 > 100 mg/L (> 5.2 mg/L)