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:
From 6 October, 2017 to 19 December, 2017
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2017
Report Date:
2017

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)
Deviations:
no
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Specific details on test material used for the study:
SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: S17-6-100
- Expiration date of the lot/batch: August 7,2018
- Purity test date: 99.4%

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: During the study, the test substance was stored as follows:
Storage condition: room temperature, dark, air-tight, nitrogen-sealed
Storage area: desiccator
- Stability under test conditions: After the exposure period, the infrared absorption spectrum of the test substance was measured. The spectrum obtained was consistent with that measured before the study, indicating that the test substance was stable under the storage conditions.
- Solubility and stability of the test substance in the solvent/vehicle: Water; >100 mg/L, Dimethylsulfoxide; >50 g/L; stable

Sampling and analysis

Analytical monitoring:
yes
Details on sampling:
- Concentrations: 100 mg/L and control (All test levels)
- Sampling method: (i) At the time of preparation: Collected from the middle layer of the vessel for measuring the test conditions of each test group
(ii) At the end of exposure: Collected from the middle layer of one vessel of each test group

Test solutions

Vehicle:
no
Details on test solutions:
PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Dilution water was aerated sufficiently.
1. The test substance was collected in conformity with the following table and the dilution water was added up to final volume.
2.The above solution was stirred for 5 minutes.
- Eluate:Elendt M4 medium
- Controls:The test solution of Control was only dilution water.

Test organisms

Test organisms (species):
Daphnia magna
Details on test organisms:
TEST ORGANISM
- Common name: Daphnia magna
- Source: National Institute for Environmental Studies, Japan
- Age of parental stock (mean and range, SD): 28 days or less

ACCLIMATION
- Acclimation period: 2-4weeks (Culture period: September 19, 2017 to October 11, 2017)
- Type and amount of food: Chlorella vulgaris (unicellular green algae), 6 mgC/2 L/day
- Health during acclimation (any mortality observed):20% or less during the 2-week period prior to the start of exposure

METHOD FOR PREPARATION AND COLLECTION OF EARLY INSTARS OR OTHER LIFE STAGES: Removed on the day offspring were produced

Study design

Test type:
static
Water media type:
freshwater
Remarks:
Elendt M4 medium
Limit test:
yes
Total exposure duration:
48 h

Test conditions

Hardness:
242 mg CaCO3/L
Test temperature:
20.0-20.1
pH:
7.3-8.0
Dissolved oxygen:
7.5-8.7
Details on test conditions:
TEST SYSTEM
- Test vessel:100-mL glass beaker
- Type (delete if not applicable): closed (cover: Teflon sheet)
- Aeration: No aeration
- Renewal rate of test solution (frequency/flow rate):None (static)
- 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: prepared Elendt M4 medium
- Culture medium different from test medium: No difference

OTHER TEST CONDITIONS
- Adjustment of pH: No adjustment
- Photoperiod:16-hour light / 8-hour dark
- Light intensity: 800 lux or less

VEHICLE CONTROL PERFORMED: None

RANGE-FINDING STUDY
- Test concentrations: 100, 10, 1.0 and 0.10 mg/L
- Results used to determine the conditions for the definitive study: there was no immobility during the concentrations. The test substance concentration was stable.
Reference substance (positive control):
yes
Remarks:
Acute immobilisation tests of the reference substance (potassium dichromate, guaranteed reagent) have been conducted periodically (approximately every 6 months).

Results and discussion

Effect concentrations
Key result
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
> 91.9 mg/L
Nominal / measured:
meas. (TWA)
Conc. based on:
test mat.
Basis for effect:
mobility
Details on results:
- Behavioural abnormalities: It was not observed
- Observations on body length and weight: Nothing
- Other biological observations: Nothing
- Mortality of control: 0%
- Other adverse effects control: None
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: None

- Effect concentrations exceeding solubility of substance in test medium: None
Results with reference substance (positive control):
- Dose-response test: Yes (periodically)
- ECx: EC50=0.64 mg/L(95% confidence limit:0.56-0.74 mg/L)

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
48-hour median effect concentration (EC50): >91.9 mg/L (95% confidence limits: not available)
Executive summary:

The result given below was calculated from the time-weighted mean of measured concentrations. The median effect concentration (EC50) for immobilisation is mentioned as [>test concentration] because this test was limit test at the maximum concentration given in the Test Guideline,and the immobility was less than 50% at this concentration.