4,4,5,5,6,6,7,7,8,8,9,9,9-tridecafluorononyl methacrylate

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: This study was selected as the key study because the information provided for the hazard endpoint is sufficient for the purpose of classification and labelling and/or risk assessment.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2005

Report date:

2005

Materials and methods

Test guideline

Test guideline 1

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

no

Remarks:

The study was conducted according to the guideline in effect at the time of study conduct.

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.3 (Algal Inhibition test)

Deviations:

no

Remarks:

The study was conducted according to the guideline in effect at the time of study conduct.

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl methacrylate

EC Number:

218-407-9

EC Name:

3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl methacrylate

Cas Number:

2144-53-8

Molecular formula:

C12H9F13O2

IUPAC Name:

3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl methacrylate

Details on test material:

- Purity: not reported

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: nominal = 0.050 mg/L; Analysis of the test preparations at 0 hours showed measured test concentrations
to range from 0.023 to 0.024 mg/l.
- Sampling method: gas chromatography (GC)
- Sample storage conditions before analysis: stored at approximately -20°C

Test solutions

Vehicle:

yes

Details on test solutions:

An amount of test material (250 mg) was dissolved in dimethylformamide and the volume adjusted to 25 mL to give a 250 mg/25 mL solvent stock solution. An aliquot (300 µL) of this solvent stock solution was dispersed in 3 litres of culture medium to give a 1.0 mg/L stock solution. This stock solution was centrifuged at 40000 g for 30 minutes to remove any undissolved test material to give a 0.050 mg/L stock solution. An aliquot (2 litres) of this stock solution was inoculated with 10 ml of algal suspension to give the required test concentration of 0.050 mg/L.

Analysis of the test preparations at 72 hours showed marked decline in measured test concentrations to less than the limit of quantitation (LOQ) of the analytical method employed. This decline in measured test concentrations was in-line with the preliminary stability analyses conducted which indicated that the test material was unstable in culture medium.

Test organisms

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

The test was carried out using Scenedesmus subspicatus strain CCAP 276/20. Liquid cultures of Scenedesmus subspicatus were obtained from the Culture Collection of Algae and Protozoa (CCAP), Institute of Freshwater Ecology, The Ferry House, Far Sawrey, Ambleside, Cumbria.
Cultures were maintained in the laboratory by the periodic replenishment of culture medium. The culture was maintained in the laboratory at a temperature of 21 ± 1°C under continuous illumination (intensity approximately 7000 lux) and shaken at approximately 150 rpm for 72 hours.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

72 h

Test conditions

Test temperature:

24 ± 1°C

pH:

7.4 to 7.5

Salinity:

fresh water

Nominal and measured concentrations:

Nominal: 0.050 mg/L
Measured at 0 Hours: 0.023 to 0.024 mg/L
Measured at 72 hours: less than the limit of quantitation (LOQ)

Details on test conditions:

TEST SYSTEM
- Test vessel: 250 mL glass conical flasks
- Type: plugged with polyurethane foam bungs
- Material, size, headspace, fill volume: 100 mL test solution
- Initial cells density: algal suspension gave an initial cell density of 1 x 10e4 cells per mL
- Control end cells density: 3.03 x 10e5 cells per mL

- No. of vessels per concentration (replicates): 6
- No. of vessels per control (replicates): 3
- No. of vessels per vehicle control (replicates): 3

GROWTH MEDIUM
- Detailed composition if non-standard medium was used:
NaNO 3 25.5 mg/l
MgCl2.6H2O 12.164 mg/l
CaCl2.H2O 4.41 mg/l
MgS04.7H2O 14.7 mg/l
K2HP04 1.044 mg/l
NaHC03 15.0 mg/l
H3B03 0.1855 mg/l
MnCl2.4H2O 0.415 mg/l
ZnCl2 0.00327 mg/l
FeCl3.6H2O 0.159 mg/l
CoCl2.6H2O 0.00143 mg/l
Na2MoO4.2H2O 0.00726 mg/l
CuCL22HzO 0.000012 mg/l
Na2EDTA.2HzO 0.30 mg/l
Na2SeO3.5HzO 0.000010 mg/l


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: reverse osmosis purified deionised water*

OTHER TEST CONDITIONS
- Sterile test conditions: yes
- Adjustment of pH: 0.1N NaOH or HCl
- Photoperiod: 24 hr
- Light intensity and quality: 7000 lux


EFFECT PARAMETERS MEASURED: 0, 24h, 48h, 72hr
- Determination of cell concentrations: Coulter® Multisizer Particle Counter

TEST CONCENTRATIONS
- Range finding study: yes
- Test concentrations: 0.065 mg/L
- Results used to determine the conditions for the definitive study: yes

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 0.008 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

dissolved

Basis for effect:

growth rate

Effect concentrations 2

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

0.008 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

dissolved

Basis for effect:

growth rate

Effect concentrations 3

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 0.008 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

dissolved

Basis for effect:

biomass

Details on results:

- Exponential growth in the control (for algal test): yes
- Observation of abnormalities (for algal test): no
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: no
- Effect concentrations exceeding solubility of substance in test medium: difficult to maintain nominal concentration, by 72 hours test substance concentration was < LOQ

Reported statistics and error estimates:

Statistical analysis of the area under the growth curve data was carried out for the solvent control and 0.050 mg/L test group using a Student's t-test incorporating Bartlett's test for homogeneity of variance (Sokal and Rohlf 1981). There were no statistically significant differences (P~0.05), between the solvent control and 0.050 mg/L test group and therefore the "No Observed Effect Concentration" (NOEC) was 0.050 mg/L.

Any other information on results incl. tables

Analysis of the test preparations at 72 hours showed marked decline in measured test concentrations to less than the limit of quantitation (LOQ) of the analytical method employed. Current regulatory advice is that in cases where a decline in measured concentrations is observed, geometric mean measured concentrations should be used for calculating EC50 values. It was therefore considered justifiable to base the results on the geometric mean measured test concentrations of the centrifuged test media in order to give a "worst case" analysis of the data. The geometric mean measured test concentration was determined to be 0.0078 mg/L. Based on the geometric mean measured test concentration of the centrifuged test media the EC50 values were estimated to be greater than 0.0078 mg/L. Correspondingly, the No Observed Effect Concentration was 0.0078 mg/L.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

This study and the conclusions which are drawn from it fulfil the quality criteria (validity, reliability, repeatability).
72-hour ErC50 > 0.0078 mg/L
72-hour NOEC = 0.0078 mg/L

Executive summary:

The toxicity of the test substance to the green algae, Scenedesmus subspicatus, was determined in a 72-hour, static toxicity test. This study was conducted as a limit test in order to confirm the effect of the test item on the test organisms at around the solubility of the test item in medium. It was concluded that the test item did not have an acute effect on the test organism at around the solubility of the test item in medium because no adverse effect was observed under the conditions of the definitive study. The 72-hour ErC50 was greater than 0.0078 mg/L and the NOEC was 0.0078 mg/L.