[No public or meaningful name is available]

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2022-02-17 to 2022-04-29

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

yes

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source: Atotech Deutschland GmbH
- Lot/batch number of test material: RR1286
- Purity, including information on contaminants, isomers, etc.: 98 %

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Keep containers tightly closed in a dry, cool and well ventilated place. Recommended storage temperature: 0 - 40 °C.
- Stability and homogeneity of the test material in the vehicle/solvent under test conditions (e.g. in the exposure medium) and during storage: Stable under recommended storage conditions
- Solubility and stability of the test material in the solvent/vehicle and the exposure medium: Soluble in water

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 0, 6.25, 12.5, 25, 50, 100 mg/L
- Sampling method: After 0 h, 24 h and 48 h exposure, the additional vessels for chemical analysis were sampled: 2 samples of 3 mL per treatment group.
- Sample storage conditions before analysis: Of each sampled treatment, one of the analytical samples from 0 h, 24 h, 48 h was sent to the analytical laboratory at the test site menal GmbH for chemical analysis, in a frozen state and one transfer using an insulated box with thermal packs.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: The stock solution was prepared by adding 100.8 mg test item to 1000 mL test medium and shaking for 35 min using an overhead shaker at 24.0 – 24.2 °C until the test item was completely dissolved. This stock solution was used as highest test item concentration in the test. The further test item concentrations were prepared by diluting the stock solution with test medium according to the following scheme (spacing factor of 2).

- Test concentration separation factor: 2
- Evidence of undissolved material (e.g. precipitate, surface film, etc.): The test item was completely dissolved

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Age at study initiation: The test organisms used were 1 - 22.25 h old at the start of the test.
- Method of breeding: The daphnids are cultured at 20 ± 2 °C with 16 h light : 8 h dark and placed into fresh Elendt M4 medium twice a week. They are kept at approx. 10 animals / 200 mL and fed on workdays with Desmodesmus subspicatus algae corresponding to 0.1 mg C × daphnid-1 × day-1
- Source: The test organism Daphnia magna Straus originates from the clone breeding of the Federal Environment Agency, department IV 2.4, Berlin, and has been cultivated at Hydrotox GmbH since October 2012.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test temperature:

The temperature during the exposure was 19.5 – 20.2 °C

pH:

The pH was 7.9 – 8.2 in the control and 7.9 – 8.6 in the test item treatment

Dissolved oxygen:

The dissolved oxygen concentration was 8.4 – 8.5 mg/L in the control and in the test item
treatment

Nominal and measured concentrations:

Nominal: 6.25, 12.5, 25, 50, 100 mg/L
Measured: 6.3, 11.7, 23.1, 48.1, 99.3 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass beakers 50 mL, Schott, Mainz
- Volume of solution: 40 mL
- Aeration: the medium was aerated for 2.7 h to achieve oxygen saturation
- 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: The test was performed with Elendt M4 medium according to OECD 202 (2004),
- Conductivity: 674 µS/cm
- Culture medium different from test medium: no
- Intervals of water quality measurement: The pH as well as the O2-concentrations were measured at the start (0 h) and at the end of the test (48 h). The temperature was measured continuously

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 h light : 8 h dark

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
The swimming capability (immobility) of the daphnids was determined after 24 h and 48 h exposure.

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):

yes

Remarks:

Reference substance was tested during routine quality assurance. Potassium dichromate was tested as reference substance in November 2021 (GLP) and an EC50 (24 h) of 2.02 mg/L was obtained which is in the declared range of 0.6 - 2.1 mg/L

Duration:

48 h

Dose descriptor:

EC10

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: No effect observed up to 100mg/L

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: No effect observed up to 100mg/L

Details on results:

As no effect on the test organisms was observed, no statistical data evaluation was performed. As
the measured test item concentrations are within ± 20 % of the nominal concentrations, according
to OECD 202 (2004), all results are given in relation to the nominal test item concentrations

Validity criteria fulfilled:

yes

Conclusions:

No adverse effect of 1,3-bis(3-(1H-imidazol-1-yl)propyl)urea on the mobility of Daphnia magna was observed up to the highest concentration of 100 mg/L.

Executive summary:

The 48-hr acute toxicity of 1,3-bis(3-(1H-imidazol-1-yl)propyl)urea to Daphnia magna was studied under static conditions according to the OECD 202 guideline. Test species were exposed to control and test chemical at nominal concentration of 6.25, 12.5, 25, 50, 100 mg/L for 48 hr. Nominal concentrations were verified by analytical measurements. No adverse effect of 1,3-bis(3-(1H-imidazol-1-yl)propyl)urea on the mobility of Daphnia magna was observed up to the highest concentration of 100 mg/L. Therefore the 48 – hour EC50 is > 100 mg/L.  

This study is classified as acceptable and satisfies the guideline requirements for an acute toxicity study with freshwater invertebrates.

 

Result synopsis

Test Organism Age: 1 - 22.25 h old at the start of the test. 

Test Type: static

EC10:  > 100 mg/L 

EC50:  > 100 mg/L

Endpoint(s) Effected:  No effects on mobility were observed

Description of key information

The 48-h EC50 value for daphnids was > 100 mg/L.

Additional information

In a 48 hour acute toxicity study, Daphnia magna was exposed to 1,3-bis(3-(1H-imidazol-1-yl)propyl)urea at concentrations up to 100 mg/L under static conditions in accordance with the OECD 202 guideline. No adverse effect of 1,3-bis(3-(1H-imidazol-1-yl)propyl)urea on the mobility of Daphnia magna was observed up to the highest concentration of 100 mg/L. Therefore the EC10 and EC50 values were >100 mg/L, respectively and no hazard was identified.