Tetra(sodium/potassium)-7-[(E)-{2-acetamido-4-[(E)-(4-{[4-chlor-6-({2-[(4-fluor-6-{[4-(vinylsulfonyl)phenyl]amino}-1,3,5-triazin-2-yl)amino]propyl}amino)-1,3,5-triazin-2-yl]amino}-5-sulfonato-1-naphthyl)diazenyl]-5-methoxyphenyl}diazenyl]-1,3,6-naphthalintrisulfonate

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Experiment start date - 04 August 2006; Experiment completion date - 15 August 2006; Study completion date - 27 October 2006.

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

yes

Remarks:

The test method was modified following a method developed by RCC Ltd (Ref. 1) to quantify not only the algicidal effect of colored test substances, but also the growth inhibition effect caused by reduced light intensities in the colored test media.

Qualifier:

according to guideline

Guideline:

EU Method C.3 (Algal Inhibition test)

Deviations:

yes

Remarks:

The test method was modified following a method developed by RCC Ltd (Ref. 1) to quantify not only the algicidal effect of colored test substances, but also the growth inhibition effect caused by reduced light intensities in the colored test media.

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Identity: FAT 40827/A
Batch: T2 5572 BOP 01/06
Purity: determined in this study
Appearance: black sticky powder
Expiration date: 28.02.2011
Storage: at room temperature

Analytical monitoring:

yes

Details on sampling:

The samples were stored deep-frozen and protected from light until analysis was performed. Treatment samples and control samples were thawed at 20 °C (water bath) for 1 hours and shaken manually to obtain homogeneous sample solutions.

Vehicle:

no

Details on test solutions:

The test medium of the highest nominal test item concentration of 100 mg/L was prepared by dissolving 59.3 mg of the test item completely in 600 mL of test water using intense stirring for 10 minutes at room temperature. The test medium was diluted with test water to prepare the test media with the lower test item concentrations. The test media were prepared just before addition of algae.

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

TEST ORGANISM
- Strain: Strain No. 86.81 SAG
- Source (laboratory, culture collection): Collection of Algal Cultures (SAG, Institute for Plant Physiology, University of Göttingen, D-37073 Göttingen, Germany).

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Remarks on exposure duration:

3 days for acclimation and 3 days for the definitive test

Hardness:

0.24 mmol/L (= 24 mg/L as CaC03)

Test temperature:

23 °C

pH:

8.2 - 9.2

Nominal and measured concentrations:

Nominal: 4.6, 10, 22, 46 and 100 mg/L
Measured: measured concentrations of the test item in the test media were between 96 to 101 % of the nominal values.

Details on test conditions:

Test water: synthetic test water:
Macro-nutrients
NaHCO3 50.0 mg/L
CaCl2 × 2 H2O 18.0 mg/L
NH4Cl 15.0 mg/L
MgSO4 × 7 H2O 15.0 mg/L
MgCl2 × 6 H2O 12.0 mg/L
KH2PO4 1.6 mg/L
Trace elements
Na2EDTA × 2 H2O 100.0 μg /L
FeCl3 × 6 H2O 80.0 μg /L
MnCl2 × 4 H2O 415.0 μg /L
H3BO3 185.0 μg /L
Na3MoO4 × 2 H2O 7.0 μg /L
ZnCl2 3.0 μg /L
CoCl2 × 6 H2O 1.5 μg /L
CuCl2 × 2 H2O 0.01 μg /L
Conductivity: <0.1 μS/cm
The test was started by inoculation of a biomass of 10.000 algal cells per ml test medium.
Test vessel: Erlenmeyer flasks (50mL)
Replicate: 3 flasks per concentration and 6 flasks in control
Each Erlenmeyer flask was placed in a black cylinder, coated inside with aluminum foil. The cylinders were covered with glass dishes, the dishes were covered with watch glass dished to prevent evaporation.

Reference substance (positive control):

no

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

37 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Remarks on result:

other: 36-39

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

18 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 18-19

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

5.2 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Remarks on result:

other: 4.7-5.6

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

10 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

4.6 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Duration:

72 h

Dose descriptor:

LOEC

Effect conc.:

22 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

LOEC

Effect conc.:

10 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Details on results:

At the higher concentrations of FAT 40827/A of 46 and 100 mg/L, the inhibitory effect on the growth of Scenedesmus subspicatus was caused in a high degree by the indirect effect, the light absorption in the colored test solutions. However, at the lower test item concentrations, the inhibitory effect of the test item in experimental part A was higher than the inhibitory effect caused by the reduced light intensity determined in experimental part B. Thus, a real toxic effect of the test item on the growth of Scenedesmus subspicatus can not be excluded. Therefore, the results of the experimental part A, where the algae grew in the test media with dissolved test item as in a usual algal growth inhibition test were taken into consideration for the determination of the toxic effect of the test item on the growth Scenedesmus subspicatus.

Validity criteria fulfilled:

yes

Conclusions:

The results of the experimental part A, where the algae grew in the test media with dissolved test item as in a usual algal growth inhibition test were taken into consideration for the determination of the toxic effect of the test item on the growth Scenedesmus subspicatus. The result of Experiment A indicated ErC50 was above 100 mg/L and NOEC was 10 mg/L.

Executive summary:

The test was performed to determine the acute toxic effects of test substance on the growth of algae and also the growth inhibition effect due to reduced light intensities in the coloured test solution during 72 hours according to the modified OECD TG 201 under GLP conditions. 4.6, 10, 22, 46 and 100 mg/L and a control of test substance were applied in the definitive test. Although no positive reference was performed in the test, for the determination of the LOEC and NOEC the calculated mean biomass and the mean growth rate at the test concentrations were tested for significant differences when compared to the control values by Dunnett-tests. Therefore, the results are still valid. The results of the experimental part A, where the algae grew in the test media with dissolved test item as in a usual algal growth inhibition test were taken into consideration for the determination of the toxic effect of the test item on the growth Scenedesmus subspicatus. The result of Experiment A indicated ErC50 was above 100 mg/L, NOEC was 10 mg/L and LOEC was 22 mg/L. Thus, the substance is not classified as per EU CLP (Regulation (EC) No 1272/2008).

Description of key information

The ErC50 was above 100 mg/L.

Key value for chemical safety assessment

EC50 for freshwater algae:

100 mg/L

EC10 or NOEC for freshwater algae:

10 mg/L

Additional information

The test was performed to determine the acute toxic effects of test substance on the growth of algae and also the growth inhibition effect due to reduced light intensities in the coloured test solution during 72 hours according to the modified OECD TG 201 under GLP conditions. 4.6, 10, 22, 46 and 100 mg/L and a control of test substance were applied in the definitive test. Although no positive reference was performed in the test, for the determination of the LOEC and NOEC the calculated mean biomass and the mean growth rate at the test concentrations were tested for significant differences when compared to the control values by Dunnett-tests. Therefore, the results are still valid. The results of the experimental part A, where the algae grew in the test media with dissolved test item as in a usual algal growth inhibition test were taken into consideration for the determination of the toxic effect of the test item on the growth Scenedesmus subspicatus. The result of Experiment A indicated ErC50 was above 100 mg/L, NOEC was 10 mg/L and LOEC was 22 mg/L. Thus, the substance is not classified as per EU CLP (Regulation (EC) No 1272/2008).