Registration Dossier

Ecotoxicological information

Short-term toxicity to aquatic invertebrates

Administrative data

short-term toxicity to aquatic invertebrates
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2006-09-20 to 2007-06-12
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP study performed according to OECD Guideline 202, and EU Method C.2 without deviations.

Data source

Reference Type:
study report
Report date:

Materials and methods

Test guidelineopen allclose all
according to guideline
OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)
The testing facility indicated that the protocol was followed without deviation.
according to guideline
EU Method C.2 (Acute Toxicity for Daphnia)
The testing facility indicated that the protocol was followed without deviation.
GLP compliance:
yes (incl. QA statement)
Certificate given by the Department of Health of the Government of the United Kingdom.

Test material

Details on test material:
- Name of test material (as cited in study report): VRT-753136 hcl
- Molecular formula: Not applicable
- Molecular weight: Not applicable
- Smiles notation: Not applicable
- InChl: Not applicable
- Structural formula attached as image file: Not applicable
- Substance type: No data
- Physical state: White powder
- Analytical purity: 100 area %
- Impurities: 0.03 area% of unknowns
- Composition of test material, percentage of components: No data
- Isomers composition: No data
- Purity test date: 2006-09-15
- Lot/batch No.: Batch number 25515/Lot No. AF6-001
- Expiration date of the lot/batch: 2008-05
- Stability under test conditions: No data
- Storage condition of test material: Room temperature
- Other: No data
Specific details on test material used for the study:
Details on properties of test surrogate or analogue material (migrated information):
Not applicable

Sampling and analysis

Analytical monitoring:
Details on sampling:
- Concentrations: All concentrations
- Sampling method: At the start of the definitive test, four samples (10 mL) were taken from the freshly prepared control and test media. After 48 hours, the contents of the vessels from each group were pooled and four samples (20 mL) were taken for analysis.
- Sample storage conditions before analysis: On each occasion, two samples from each batch were analysed immediately; the other samples were stored frozen in case further analysis was required.

Test solutions

Details on test solutions:
PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: The test substance (50 mg) was dissolved in dilution medium (500 mL) in a volumetric flask. The contents of the flask were shaken and used directly as the test medium.
- Eluate: Not applicable
- Differential loading: Not applicable
- Controls: Elendt M4 media
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): Not applicable
- Concentration of vehicle in test medium (stock solution and final test solution): Not applicable
- Evidence of undissolved material (e.g. precipitate, surface film, etc.): No

Test organisms

Test organisms (species):
Daphnia magna
Details on test organisms:
- Common name: Water flea
- Strain: Straus
- Source: In-house culture, originally from the Institute National de Recherche Chimiqhue Applique, France
- Age at study initiation (mean and range, SD): <24 h
- Weight at study initiation (mean and range, SD): Not applicable
- Length at study initiation (length definition, mean, range and SD): Not applicable
- Valve height at study initiation, for shell deposition study (mean and range, SD): Not applicable
- Peripheral shell growth removed prior to test initiation: Not applicable
- Method of breeding: reproduce by parthenogenesis
- Feeding during test: No

- Acclimation period: No
- Acclimation conditions (same as test or not): Not applicable
- Type and amount of food: Not applicable
- Feeding frequency: Not applicable
- Health during acclimation (any mortality observed): Not applicable

QUARANTINE (wild caught)
- Duration: Not applicable
- Health/mortality: Not applicable

Study design

Test type:
Water media type:
Limit test:
Total exposure duration:
48 h
Post exposure observation period:

Test conditions

260 mg/L
Test temperature:
The temperature ranged from 19.3 -19.6 deg C at time 0 and 20.7-20.8 deg C at time 48 h.
The pH ranged from 7.62 – 7.79 at time 0 and 7.51-7.93 at time 48 h.
Dissolved oxygen:
The DO ranged from 102-103% of air saturation at time 0 and 105% at time 48 h.
Not applicable
Nominal and measured concentrations:
Nominal- Control (100 mg/L)
Mean measured- Control (97.8 mg/L)
The measured concentration of VRT-753136 hcl in samples of test medium was corrected for the procedural recovery performed with the analysis on each occasion. They ranged between 94 and 100% of the nominal value during the test, giving an overall mean measured level of 97.8 mg/L.
Details on test conditions:
- Test vessel:
- Type (delete if not applicable): closed; loosely covered
- Material, size, headspace, fill volume: glass vessels, 100 mL fill volume
- Aeration: No
- Type of flow-through (e.g. peristaltic or proportional diluter): Not applicable
- Renewal rate of test solution (frequency/flow rate): Daphnia were exposed to the test or control conditions for a period of 48 hours without renewal of test media.
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
- No. of vessels per vehicle control (replicates): Not applicable
- Biomass loading rate: 20 mL media per organism

- Source/preparation of dilution water: Elendt M4 test media; the medium was prepared in de-ionised water produced by reverse osmosis.
- Total organic carbon: Not applicable
- Particulate matter: Not applicable
- Metals: Not applicable
- Pesticides: Not applicable
- Chlorine: Not applicable
- Alkalinity: 43 mg/L
- Ca/Mg ratio: nominally 0.1 to 0.2 mg carbon per daphnid
- Conductivity: Not applicable
- Culture medium different from test medium: No
- Intervals of water quality measurement: Daily

- Adjustment of pH: yes
- Photoperiod: A photoperiod of 16 hours light : 8 hours dark was maintained, with periods of subdued lighting at the beginning and end of each light phase.
- Light intensity: no data

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): Immobility, 24 and 48 h; Daphnia were considered to be immobile if they were unable to swim within approximately 15 seconds following gentle agitation of the test vessel.

- Spacing factor for test concentrations: Not applicable
- Justification for using less concentrations than requested by guideline: Not applicable
- Range finding study
- Test concentrations: 1, 10, and 100 mg/L
- Results used to determine the conditions for the definitive study: Yes
Reference substance (positive control):

Results and discussion

Effect concentrationsopen allclose all
48 h
Dose descriptor:
Effect conc.:
> 97.8 mg/L
Nominal / measured:
meas. (arithm. mean)
Conc. based on:
test mat.
Basis for effect:
48 h
Dose descriptor:
Effect conc.:
97.8 mg/L
Nominal / measured:
meas. (arithm. mean)
Conc. based on:
test mat.
Basis for effect:
Details on results:
- Behavioural abnormalities: No data
- Observations on body length and weight: Not applicable
- Other biological observations: Two control and four test Daphnia were observed at the surface of the medium (floating) after 24 hours of exposure; these animals were re-submerged and remained within the body of the media for the remainder of the test. After 48 hours, no immobility was observed.
- Mortality of control: One control animal appeared to be immobile after 48 hours.
- Other adverse effects control: No data
- Abnormal responses: No data
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: No data
- Effect concentrations exceeding solubility of substance in test medium: No data
Results with reference substance (positive control):
Not applicable
Reported statistics and error estimates:
The “no-observed-effect concentration” (NOEC) is derived by direct inspection of the data on the immobility of the animals. An incidence rate of more than 10% is considered to be significant.

Any other information on results incl. tables

Not applicable

Applicant's summary and conclusion

The 48-hour EC50 of VRT-753136 hcl for the immobilisation of Daphnia magna could not be identified but must be >97.8 mg/L.
The ‘no-observed effect concentration’ of VRT-753136 hcl to Daphnia magna was 97.8 mg/L.

Executive summary:

Not applicable