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:
2-6 September 2019
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2019
Report Date:
2019

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)
Version / remarks:
Apr. 2004
Deviations:
yes
Remarks:
Uncritical deviation: no acclimatation period. Switching from M4-medium (husbandry) to Dilution water (test) has been shown not to cause any detrimental effects for test daphnia, therefore no acclimation period of 48 h was performed.
Qualifier:
according to
Guideline:
EU Method C.2 (Acute Toxicity for Daphnia)
Version / remarks:
May 2008
Deviations:
yes
Remarks:
idem as above
GLP compliance:
yes (incl. certificate)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Type:
Constituent
Type:
Constituent
Test material form:
liquid: viscous

Sampling and analysis

Analytical monitoring:
yes
Details on sampling:
- Sampling method: the content of the test item was estimated in the test solutions at the start and the end (48 h) of the test

Test solutions

Vehicle:
no
Details on test solutions:
PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: The water-accommodated fraction (WAF) was prepared for the test. This was done by mixing the nominal load of 100 mg/L resp. 108.7 µL/L test item (based on a density of 0.92 g/mL stated in the SDS) with the corresponding amount of dilution water and stirring moderately for 24 hours at 120 rpm on a magnetic stirrer. The lower phase was used unfiltered as test solution
- Evidence of undissolved material: No turbidity of the test solution was visible.

Test organisms

Test organisms (species):
Daphnia magna
Details on test organisms:
TEST ORGANISM
- Species: Daphnia magna Straus
- Strain: Berlin
- Age at study initiation: 0-24 hours
- Sex: female
- Source: Umweltbundesamt Berlin
- Feeding during test: no
- Food type: Desmodesmus subspicatus - during breeding only

ACCLIMATION
- Acclimation period: none: Switching from M4-medium (husbandry) to Dilution water (test) has been shown not to cause any detrimental effects for test daphnia, therefore no acclimation period of 48 h was performed.

METHOD FOR PREPARATION AND COLLECTION OF EARLY INSTARS OR OTHER LIFE STAGES, INCLUDING CULTURING CONDITIONS: Daphnia magna was bred in the LAUS GmbH throughout the year. The animals are kept for the use in toxicity tests. They multiply by parthenogenesis, thus being genetically identical. The keeping is performed similar to the method described in the OECD guideline.
Vessels preserving glasses, nominal volume 2 L
Medium M4-Medium (recipe of ELENDT)
Food green algae (Desmodesmus subspicatus)
Medium renewal twice a week
Photo period 16/8 hours, using neon tubes
Temperature 20 +/- 2 °C

Study design

Test type:
static
Water media type:
freshwater
Limit test:
yes
Total exposure duration:
48 h
Remarks on exposure duration:
Observations after 24 and 48 h.
Post exposure observation period:
not applicable

Test conditions

Hardness:
no data
Test temperature:
18.9 - 20.5°C
pH:
7.5 - 7.6
Dissolved oxygen:
8.3 - 8.4 mg/L
Salinity:
not applicable
Conductivity:
no data
Nominal and measured concentrations:
Loading rate: 100 mg/L
Details on test conditions:
TEST SYSTEM
- Test vessel: glass beakers
- Type: open
- Fill volume: 50 mL beakers containing 20 +/- 5 mL test solution
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water:For preparation of the dilution water demineralised water was used, with the following specifications: 293.80 mg/L CaCl2*2H2O, 123.30 mg/L MgSO4*7H2O, 64.80 mg/L NaHCO3 and 5.80 mg/L KC. Deviations from the nominal weighted loads were less than 5 %. Exact values are rec-orded in the raw data. After preparation, the dilution water was aerated and the pH was measured. The pH was 7.6.
- Total organic carbon: 0.97 - 1.11 mg/L

EFFECT PARAMETERS MEASURED : immobility every 24 h

RANGE-FINDING STUDY : yes
- Test concentrations: 1, 10 and 100 mg/L in a non-GLP pre-test
- Results used to determine the conditions for the definitive study: yes, no toxicity observed at highest tested dose.
Reference substance (positive control):
yes
Remarks:
potassium dichromate

Results and discussion

Effect concentrationsopen allclose all
Key result
Duration:
48 h
Dose descriptor:
NOELR
Effect conc.:
>= 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat. (dissolved fraction)
Basis for effect:
other: immobility
Key result
Duration:
48 h
Dose descriptor:
EL50
Effect conc.:
>= 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat. (dissolved fraction)
Basis for effect:
other: immobility
Results with reference substance (positive control):
- Results with reference substance valid? yes
- Relevant effect levels: The value was within the requested range for the 24h-EC50 between 0.6 - 2.1 mg/L of potassium dichromate K2Cr2O7 as specified in the OECD guideline.
- ECx: The 24h-EC50 value was determined as 1.98 mg/L.
Reported statistics and error estimates:
Since no immobility has occurred, no statistical evaluation was carried out.

Any other information on results incl. tables

Non-GLP pre-test

Nominal Concentration in mg/L

Immobility 48 hours

absolute

in %

Blank control

0

0

0

1

0

0

0

10

0

0

0

100

0

0

0

Main test

Nominal Concentration in mg/L

Immobility 24 hours

Immobility 48 hours

absolute

in %

absolute

in %

Blank control

0

0

0

0

0

0

0

0

0

0

100

0

0

0

0

0

0

0

0

0

0

Analytical determinations

The concentrations measured in the test solutions are in the same very low range as the blank value. It is detectable but not quantifiable. During the preparation of the WAF, the test solutions were in direct contact with the test item while stirring. This means that the soluble components must have dissolved. Therefore, the results are related to the loading rate; see Guidance Doc. No.23 (§176).

Measured concentrations IC and TC

Nominal
Concentration Test Item

Measured

TC
 t = 0 h

Measured

TC
 t = 48 h

Measured

IC
 t = 0 h

Measured

IC
 t = 48 h

mg/L

mg/L

mg/L

mg/L

mg/L

Blank control

10.41

11.77

9.44

10.66

100

10.30

12.34

10.10

10.70

LOQ (Limit of quantification) TC = 822.33 µg/L

LOQ (Limit of quantification) IC = 447.52 µg/L

Calculated concentrations TOC

Nominal
Concentration Test Item

Calculated concentration TOC (TC-IC)
 t = 0 h

Calculated concentration TOC (TC-IC)
 t =48 h

Calculated concentration TOC minus blank control
t = 0 h

Calculated concentration TOC minus blank control t = 48 h

mg/L

mg/L

mg/L

mg/L

mg/L

Blank control

0.97

1.11

--

--

100

0.20

1.65

-0.77

0.54

Calculated test item concentrations

Nominal
Concentration Test Item

Calculated

Concentration

t = 0 h

Calculated

Concentration

t = 48 h

% of Nominal concentration
t = 0 h

% of Nominal concentration
t = 48 h

mg/L

mg/L

mg/L

%

%

Blank control

--

--

--

--

100

-1.0

0.7

-1

1

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
A 48h exposure of the test item at 100 mg/L WAF did not induce any immobility of Daphnia magna. Results indicated an NOELR and EL50 >= 100 mg/L.
Executive summary:

A study performed as limit study in a Water Accommodated Fraction (WAF) test setup exposing the crustacean, Daphnia magna, for 48 h to load of 100 mg/L (loading rate) of the test item. Test was performed according to the OECD guideline 202 and it fulfilled the validity criteria. The test solution was prepared following the water-accommodated fractions (WAF) method at the load of 100 mg/L. Measured concentrations were determined using measurement of total organic carbon (TOC). The concentrations measured in the test solutions are in the same very low range as the blank value. It is detectable but not quantifiable. Therefore, the results are related to the loading rate; see Guidance Doc. No.23 ( § 153). No immobilisation was observed after 48 h, determining a NOELR, LOELR and EL50 greater than 100 mg/L.