3,4,5-trifluoro-4'-(trans-4-propylcyclohexyl)-[1,1'-biphenyl]

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

Study period:

March 28, 2000 - July 17, 2000

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2000

Report date:

2000

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Version / remarks:

adopted 7 June, 1984

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.3 (Algal Inhibition test)

Version / remarks:

Official Journal No. L 383 A, December 29, 1992

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

4-trans-Propyl-4-trans-(3,4,5-trifluorphenyl)-[1,1-bicyclohexyl]

EC Number:

603-522-2

Cas Number:

131819-23-3

Molecular formula:

C21H29F3

IUPAC Name:

4-trans-Propyl-4-trans-(3,4,5-trifluorphenyl)-[1,1-bicyclohexyl]

Test material form:

solid

Specific details on test material used for the study:

Batch No.: E99833354
Storage: tightly closed, dark, at room temperature

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

A filtrate of the test material preparation (0.1 g/L nominally) was taken at the start of the experimental part of the study and at the end of the exposure period for analyses. Two samples of about 20 ml filtrate were filled in siliconized glass bottles. They were stored deeply frozen (at least –18°C) until analyses.

Test solutions

Vehicle:

yes

Details on test solutions:

Preparation of the Test Item:
The test medium (reconstituted water and test material) was freshly prepared.
Therefore, the calibrated flask with test material and vehicle (reconstituted water) was treated in an ultrasonic device for 1 hour. Subsequently, the preparation was aerated and stirred with a magnetic stirrer for further 23 hours. After 24 hours the formulation was given through a nutsch filter (pore size >10 - <16 µm). The filtrate of the test material preparation was used for the study.

Test organisms

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

TEST ORGANISM
- Common name: Unicellular green algae
- Strain: Desmodesmus subspicatus
- Source (laboratory, culture collection): The test system used was Desmodesmus subspicatus, strain No. SAG 86.81 (Sammlung von Algenkulturen, Pflanzenphysiologisches Institut der Universität Göttingen, Germany). This strain was further cultivated in the laboratories of the Institute of Toxicology.

ACCLIMATION
- Acclimation period: 72h
- Culturing media and conditions (same as test or not): same as test
- Any deformed or abnormal cells observed: no

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

72 h

Post exposure observation period:

-

Test conditions

Test temperature:

23 - 24°C

pH:

7.81 - 7.87

Nominal and measured concentrations:

Nominal concentrations: 100.0 mg/L (measured: < 0.00289 g/L)

Details on test conditions:

TEST SYSTEM
- Test vessel: 300 mL Erlenmeyer flasks
- Type: open
- Material, size, headspace, fill volume: 300 mL Erlenmeyer glas flasks filled with 100 mL cell suspension
- Aeration: no
- Initial cells density: 10 000 cells per ml
- Control end cells density: 1 496 418 cells per ml
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 3


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: reconstituted water according to OECD TG 201

Macro-nutrients:
NaHCO3 50.0 mg/L
CaCl2 x 2 H2O 18.0 mg/L
NH4Cl 15.0 mg/L
MgSO4 x 7 H2O 15.0 mg/L
MgCl2 x 6 H2O 12.0 mg/L
KH2PO4 1.6 mg/L

Trace elements:
Na2EDTA x 2 H2O 100.0 µg/L
FeCl3 x 6 H2O 80.0 µg/L
MnCl2 x 4 H2O 415.0 µg/L
H3BO3 185.0 µg/L
Na2MoO4 x 2 H2O 7.0 µg/L
ZnCl2 3.0 µg/L
CoCl2 x 6 H2O 1.5 µg/L
CuCl2 x 2 H2O 0.01 µg/L

- pH: 7.81

OTHER TEST CONDITIONS
- Sterile test conditions: yes
- Adjustment of pH: no
- Light intensity and quality: 6700 to 9000 Lux


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: electronic particle counter

TEST CONCENTRATIONS
- Nominal test concentration: 100 mg/L

Reference substance (positive control):

no

Remarks:

The accuracy and reliability of the test method is demonstrated periodically as recommended by OECD Guideline No. 201.

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: EC10 >0.00289 g/L

Effect concentrations 2

Key result

Duration:

72 h

Dose descriptor:

EC20

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: EC20 >0.00289 g/L

Effect concentrations 3

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: EC50 >0.00289 g/L

Details on results:

The 72 hour EC50 for the test material to Desmodesmus subspicatus could not be quantified. An aqueous filtrate of nominal 0.1 g test item/ L, corresponding to an analytical concentration of <0.00289 g/L, revealed no inhibition of algal growth in this test system.

- Observation of abnormalities (for algal test): no
- Unusual cell shape: no
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: no

Results with reference substance (positive control):

The accuracy and reliability of the test method is demonstrated periodically as recommended by OECD Guideline No. 201.

Any other information on results incl. tables

Objective

The objective of this study was to evaluate the influence of the test material on the growth of the green algal species Desmodesmus subspicatus in a static test.

Study Design

For this purpose green algae were exposed to an aqueous filtrate of the test material preparation under defined conditions. The growth was calculated after 24, 48, and 72 hours exposure in the test medium. The algae were exposed to an aqueous filtrate of a nominal test material concentration of 0.1 g/L and the study was performed as limit test.

Results

Samples for analysis were taken from the test material filtrate directly after preparation and at the end of the exposure period. The analytically determined test material concentrations were below the limit of quantification of about 0.00289 g/L.

No effect on growth of the algae was observed at a nominal concentration of 100 mg/L.

For the test item the following EC values were determined:

Parameter (0 -72h)	Growth Rate
EC10 [mg/L]  95% confidence interval	>0.00289 g/L (nominal >100 mg/L) n.d.
EC20 [mg/L] 95% confidence interval	>0.00289 g/L (nominal >100 mg/L) n.d.
EC50 [mg/L] 95% confidence interval	>0.00289 g/L (nominal >100 mg/L) n.d.

Conclusion

The 72 hour EC50 for the test material to Desmodesmus subspicatus could not be quantified. An aqueous filtrate of nominal 0.1 g test item/ L, corresponding to an analytical concentration of <0.00289 g/L, revealed no inhibition of algal growth in this test system.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The 72 hour EC50 for the test material to Desmodesmus subspicatus could not be quantified. An aqueous filtrate of nominal 0.1 g test item/ L, corresponding to an analytical concentration of <0.00289 g/L, revealed no inhibition of algal growth in this test system.

Executive summary:

This study was performed according to GLP and the methods applied are fully compliant with OECD TG 201. The 72 hour EC50 for the test material to Desmodesmus subspicatus could not be quantified. An aqueous filtrate of nominal 0.1 g test item/ L, corresponding to an analytical concentration of <0.00289 g/L, revealed no inhibition of algal growth in this test system.