3,5-di(undecan-2-yl)heteropolycycle

Toxicity to aquatic algae and cyanobacteria

Administrative data

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study and GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2009

Report date:

2009

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.3 (Algal Inhibition test)

Deviations:

yes

Remarks:

, see "prinicples of method if other than guideline"

Principles of method if other than guideline:

ln OECD Guideline 201 and EU Method C.3, different compositions of stock solution ll are
stated. The study was conducted in accordance with OECD Guideline 201, therefore, the
composition of stock solution ll must be stated as deviation from EU Method C.3.

GLP compliance:

yes (incl. QA statement)

Test material

Reference

Name:

Unnamed

Type:

Constituent

Sampling and analysis

Analytical monitoring:

yes

Test solutions

Vehicle:

yes

Test organisms

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

72 h

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

7 µg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: limit of water solubility

Effect concentrations 2

Duration:

72 h

Dose descriptor:

LOEC

Effect conc.:

> 7 µg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: limit of water solubility

Effect concentrations 3

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 7 µg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: limit of water solubility

Any other information on results incl. tables

Two experiments were performed. Because of the algae celts in the samples after 72 hours, sample preparation via solid phase extraction wasn't possible (cartridges became clogged during extraction). Therefore the first experiment was aborted. In the second experiment, the samples after 72 hours were centrifuged. The results of the first study aren't reported- The main study was performed as a limit test using one concentration in the range of water solubility. The water solubility was determined as approximately 7 µg/L. At the start and at the end of the test, the content of the test item in the test solutions was determined using GC. In both experiments the measured values at the start of the test were in the range of water solubility. As the test item wasn't stable in under test conditions, the measured concentrations test item after 72 hours were lower than LOQ. The treatment was used to incubate the unicellular freshwater green algae Desmodesmus subspicatus for a period of 72 hours. The cell concentration of each replicate was determined by measuring the absorption of the cuvettes at 440 nm every 24 hours with a spectral photometer. With these measured values, the number of cells was calculated (linear correlation between cell concentration and absorption given). Then the growth rate, the area under the growth cunte (AUC) and the Yield were determined. The determination of the results was based on the limit of water solubility. The EC50s of potassium dichromate was tested in a current reference test. The values were within the normal range of the laboratory.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

All validity criteria were met.
The EC50s of potassium dichromate were determined in a current reference test. For the
estimation of the EC50s of the positive control, the fits showed sufficient statistical correspondence
of the data with the dose-response-equation. The values were within the normal
range of the laboratory as well as in correspondence with the values from the international
ring test which are stated in EU Method C.3.
The study was performed as a limit test in the range of water solubility. The water solubility
was determined as approximately 7 µg/L. To produce a test solulion in the range of water
solubility a stock solution containing 87.5 mg/L test item in methanol was used for the
preparation of the test solution (0.1 ml/L). The first study was aborted because of too much
algae cells the samples after 72 hours couldn't be measured (cartridges became clogged
during extraction). Therefore the samples in the second experiment were centrifuged before
sample preparation with solid phase extraction.
At the beginning of the test, the measured concentrations were in the range of water solubility
in both experiments. At the end of the test, no test item could be detected. The samples
after 72 hours were shipped on Friday 23.10.2009 and arrived at the test site not until
Tuesday 27.10.2009. As validation of the analytical method showed that the test item
wasn't stable under test conditions, but stable in solvent, this can be stated as uncritical.
Therefore the limit of water solubility was used for the determination of the results.
The result of the test can be considered valid.