Registration Dossier

Ecotoxicological information

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:
short-term toxicity to aquatic invertebrates
Type of information:
experimental study
Adequacy of study:
key study
Study period:
20 Dec 2017 - 31 Jan 2018
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2018
Report Date:
2018

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)
Version / remarks:
2004
Deviations:
no
GLP compliance:
yes (incl. certificate)
Remarks:
Landesanstalt für Umwelt, Messungen und Naturschutz Baden-Württemberg, Karlsruhe, Germany

Test material

Reference
Name:
Unnamed
Type:
Constituent

Sampling and analysis

Analytical monitoring:
yes
Details on sampling:
- Sampling method: Analytical samples taken at 0 hours (initial value) and 24 hours from fresh and 24 hours and 48 hours from aged test solutions were analysed from control and all test item concentrations. Two sample sets were taken. For each sampling also retain samples were taken.
- Sample storage conditions before analysis: All samples were stored deep frozen until they were transferred to the analytical laboratory.

Test solutions

Vehicle:
no
Details on test solutions:
PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: The necessary amount of test item for preparing the stock solution was weighed on a weighing scoop and transferred to a volumetric flask. Test medium was added up to the bench mark and the solution was homogenised by shaking. Lower test solutions were prepared by dilution of the appropriate solution with test medium. Approx. 50 mL of the prepared solutions were transferred to each test vessel.
- Controls: blank control without the test item
- Eluate: no
- Differential loading: no
- Evidence of undissolved material (e.g. precipitate, surface film, etc.): The solution was clear and transparent after homogenisation by shaking.

Test organisms

Test organisms (species):
Daphnia magna
Details on test organisms:
TEST ORGANISM
- Common name: water flea
- Source: Continuously bred in the laboratory and originally purchased in a healthy condition from the Federal Environment Agency in Berlin/Germany.
- Age: Freshly hatched daphnids less than 24 hours old were used for the test.
- Breeding conditions: Daphnia magna was bred as single culture (1 daphnid per 100 mL) in Elendt M4 medium. The pHvalue of the aerated water was within a range of 6.0 – 9.0. The dissolved oxygen was above 60 % saturation and the total hardness 140 - 250 mg/L (as CaCO3), corresponding to 7.8 - 14°dH. The animals were fed with single cell green algae (Desmodesmus subspicatus, formerly Scenedesmus subspicatus) at least three times a week. The daphnids were reared at a temperature of 20 ± 2 °C in a climatic chamber with 16 hours of illumination and 8 hours of darkness.

Study design

Test type:
semi-static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
48 h

Test conditions

Hardness:
12°dH (214 mg/L as CaCO3)
Test temperature:
19.5 ± 0.4
pH:
7.84 ± 0.10
Dissolved oxygen:
8.9 ± 0.2 mg O2/L
Nominal and measured concentrations:
nominal: 10.0, 4.55, 2.07, 0.939, 0.427 mg/L, and control
measured: 9.07-10.1, 4.28-4.22, 1.92-2.08, 0.849-0.930, 0.382-0.392 mg/L, and < LOD
Details on test conditions:
TEST SYSTEM
- Test vessel: Glass vessel (100 mL), were filled up with ~ 50 mL test solution. The test units were covered with a glass plate.
- Renewal rate of test solution: The test solutions were freshly prepared at 0 and 24 h.
- Aeration: no
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Elendt M4 standard medium was used as test medium. At test initiation the pH-value of the control (untreated test medium) was 7.61, the dissolved oxygen concentration was 9.0 mg/L and the total hardness was 12°dH (214 mg/L as CaCO3).
- Intervals of water quality measurement: The test temperature and the pH-value as well as the oxygen concentration of the test solutions were measured at all loading rates and control at t = 0 h fresh and t = 24 h from fresh test solutions and after t = 24 h and t = 48 h from aged test solutions in one separate replicate per test item loading rate without test organisms.

OTHER TEST CONDITIONS
- Photoperiod: 16 hours photoperiod /8 hours darkness daily

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Immobility after 24 and 48 h
- Behavioural changes of daphnids were recorded at 24 and 48 hours after starting the test.

RANGE-FINDING STUDY
- A range finder was performed but the results are not reported.
Reference substance (positive control):
yes
Remarks:
potassium dichromate

Results and discussion

Effect concentrationsopen allclose all
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
4.04 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Remarks on result:
other: 95% CI: 3.54 - 4.60 mg/L
Duration:
48 h
Dose descriptor:
NOEC
Effect conc.:
2.07 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Details on results:
- Mortality of control: 0%
- Behavioural changes: No behavioural changes were observed.
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: No; Test solutions were clear and colorless
Results with reference substance (positive control):
- Results with reference substance valid? yes
- EC50 (24 h) < 1.00 mg/L
Reported statistics and error estimates:
The 24 h and 48 h EC50 are the calculated concentrations where 50 % of the daphnids were immobilised after 24 and 48 hours, respectively. The values for EC50 were determined by Weibull analysis using linear max. likelihood regression. The evaluation of data was performed by ToxRat Professional 3.2.1. The NOEC was established based on the highest concentration at which the immobilisation is not higher than the allowed control immobilisation (≤ 10 % immobilisation).

Any other information on results incl. tables

Table 1: Determined concentration of the test substance

Test item

Test substance

Sampling

Test substance

nominal [mg/L]

nominal [mg/L]

[h]

[mg/L]

% of nominal

Control

0

0 fresh

n.d.

-

24 aged

n.d.

-

24 fresh

n.d.

-

48 aged

n.d.

-

0.427

0.427

0 fresh

0.382

89

24 aged

0.388

91

24 fresh

0.388

91

48 aged

0.392

92

0.939

0.939

0 fresh

0.849

90

24 aged

0.930

99

24 fresh

0.892

95

48 aged

0.915

97

2.07

2.07

0 fresh

2.03

98

24 aged

2.08

100

24 fresh

1.92

93

48 aged

1.94

94

4.55

4.55

0 fresh

4.42

97

24 aged

4.40

97

24 fresh

4.28

94

48 aged

4.30

95

10.0

10.0

0 fresh

9.65

97

24 aged

10.1

101

24 fresh

9.07

91

48 aged

9.50

95

 - = not calculated; n.d. = not detectable; LOQ = 0.0400 mg/L test substance

Table 2:         Results of the test, 48 h values

 

Nominal test item concentration [mg/L]

 

Control

0.427

0.939

2.07

4.55

10.0

 

Immobilised daphnids after 48 h

Group 1

0

0

0

0

5

5

Group 2

0

0

0

0

2

5

Group 3

0

0

0

0

2

5

Group 4

0

0

0

0

5

5

Σ

0

0

0

0

14

20

%

0

0

0

0

70

100

Table 3: Validity criteria

Criterion from the guideline

Outcome

Validity criterion fulfilled

In the control, including the control containing the solubilising agent, not more than 10% of the daphnids should have been immobilized.

Control: 0%

 yes

The dissolved oxygen concentration at the end of the test should be ≥ 3 mg/L in control and test vessels.

 ≥ 8.6 mg/L

 yes

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Remarks:
For further details please refer to “Any other information on results incl. tables”.