1-ethyl-3-methyl-3H-imidazolium dicyanidoamide(1-)

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

no

Remarks:

Scientific research

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Name of test material (as cited in publication): 1-ethyl-3-methylimidazolium dicyanimide (IM12 [N(CN)2])
- Source: Merck KGaA (Darmstadt, Germany)
- Purity: ≥ 97%

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

Direct application in the medium.

Test organisms (species):

Daphnia magna

Details on test organisms:

The assessment of the test was carried out using the commercially available DaphToxkit (MicroBioTest Incorporation, Gent, Belgium).
- Age of test organisms at study initiation: less than 24 hours old
- Feeding: the organisms were pre-fed

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test temperature:

20 °C

Nominal and measured concentrations:

5 different concentration and a control were investigated, concentrations are not further specified.

Details on test conditions:

TEST SYSTEM
- Fill volume: 10 mL
- No. of organisms per vessel: 5
- No. of vessels per concentration: 5
- No. of vessels per control: 5
- Other: The experiment was conducted twice

OTHER TEST CONDITIONS
- Illumination: tests were performed in the dark

EFFECT PARAMETERS MEASURED: Immobility or mortality was recorded after 24 and 48 h.

Reference substance (positive control):

yes

Remarks:

The sensitivity of the organisms to K2Cr2O7 was checked routinely once a new batch of organisms was obtained.

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

150 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: corresponds to 860 µM (97.5% C.I.: 820 - 900 µM)

Results with reference substance (positive control):

No data presented.

Reported statistics and error estimates:

Dose-response curve parameters and plots were done using the drfit package (version 0.05-92) for the R language and environment for statistical computing.

Validity criteria fulfilled:

not specified

Reference 2

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

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 (incl. QA statement)

Analytical monitoring:

yes

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
The nominal concentrations were prepared by dilution of a stock solution of the test substance in aerated Daphnia medium. 100 ml of the test solutions were filled in the first of the two replicate test vessels. The solution was aerated by stirring for about 0.5 h. O2 concentration and pH was measured. The pH was adjusted, where necessary. Subsequently, half of the solution (50 ml) was filled in the 2nd replicate test vessel.

Test organisms (species):

Daphnia magna

Details on test organisms:

Daphnia magna STRAUS
- Age: less than 24 h
- Feed: Suspension of Desmodesmus subspicatus in Elendt M4 medium with an optical density OD680 of about 15 units; 400 μl per Daphnia per day, except on weekends

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

2.52 mmol/L

Test temperature:

22 °C

pH:

7.1 - 7.4

Dissolved oxygen:

6.0 - 6.5 mg/L

Nominal and measured concentrations:

- Nominal concentrations: 0 (control), 25.0, 50.0, 100, 200 and 400 mg/L

Details on test conditions:

TEST SYSTEM
- Number of Daphnia: 40 individuals per test concentration, 20 per vessel
- Test vessel: 100 ml flasks, all-glass, with 50 ml of test medium
- Replicates: 2 replicates with test animals (20 animals per replicate); 3 replicates as blank controls

TEST MEDIUM
- Medium: Contious aerated Elendt M4 medium; prepared with deionised water (conductivity <1.5 µS/cm)

OTHER TEST CONDITIONS
- Light: 16 h photoperiod a day, supplied by oberhead white fluorescent tubes

EFFECT PARAMETERS MEASURED: Observations of immobile Daphnia were made after 24 and 48 h of exposure.

Reference substance (positive control):

yes

Remarks:

potassium dichromate (Acute reference test with potassium dichromate conducted twice a year)

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

190 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 53.2-346

Duration:

48 h

Dose descriptor:

EC10

Effect conc.:

84.8 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 0.544-149

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

106 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

other: cation

Basis for effect:

mobility

Remarks on result:

other: 21.4-199

Duration:

48 h

Dose descriptor:

EC10

Effect conc.:

48.9 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

other: cation

Basis for effect:

mobility

Remarks on result:

other: 0.049-85.1

Reference 3

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

no

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Name of test material (as cited in publication): 1-Ethyl-3-methylimidazolium dicyanamide [EMIM] [DCA]
- Source: BASF et CYTEC
- Purity: ≥ 98%

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

The required amount of the test substance was introduced directly into dilution water, which was then magnetically stirred for 2 minutes.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISMS
- Common name: Water flea
- Clone: Straus (clone A)
- Age: Neonate organisms of less than 24 hours old, obtained from parthogenetic females of 2 to 5 weeks old were selected for the test.

ACCLIMATION
- Acclimation conditions: The test organisms were kept in a 5 L glass beaker, filled with 2 L of Elendt M4 medium with a temperature of 18 - 22 °C and 16-h light:8-h dark photoperiod. The medium was renewed once every week.
- Feeding: In the stock culture the organisms were fed with unicellular green algae (Chlorella vulgaris/Desmodesmus subspicatus).
- Loading rate: In the stock culture, a loading rate of 20 animals per litre was maintained.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test temperature:

18 - 22 °C

Nominal and measured concentrations:

The nominal concentrations of the test substance ranged from 47.7 to 500 mg/L. The concentrations were based on previous preliminary range-finding tests. No further specification given.

Details on test conditions:

TEST SYSTEM
- Test vessel: glass test tubes
- Fill volume: 10 mL
- No. of organisms per vessel: 5
- No. of vessels per concentration: 4
- No. of vessels per control: 4

OTHER TEST CONDITIONS
Tests were performed in the dark

EFFECT PARAMETERS MEASURED: Immobilisation was recorded after 24 and 48 hours exposure.

Reference substance (positive control):

yes

Remarks:

The sensitivity to K2Cr2O7 was investigated to validate the selected batches of test organisms.

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

247.3 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% C.I.: 248.5 - 298.4 mg/L

Remarks:

test 1

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

268.9 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% C.I.: 231.7 - 255.1 mg/L

Remarks:

test 2

Results with reference substance (positive control):

No data presented.

Reported statistics and error estimates:

EC50 values were calculated from the concentration-response curves using a logistic Hill model. The 95% confidence intervals were estimated using a “bootstrap” simulation method. Calculations were done with REGTOX software v.7.0.5.

Validity criteria fulfilled:

not specified

Description of key information

The 48-h EC50 value is 190 mg/L in aquatic invertebrates (Daphnia magna).

Additional information

The acute toxicity to aquatic invertebrates was determined according to OECD TG 202 and in compliance with GLP criteria (BMG, 2013). In this study daphnids (D. magna, 40 per concentration) were exposed to nominal concentrations of 0 (control), 25, 50, 100, 200 and 400 mg/L under static conditions. Nominal test concentrations were analytically confirmed. The effect concentrations are expressed as the geometric mean of the measured concentrations. Mobility was scored as parameter for toxicity. The 48-h EC50 value of the test substance was determined at 190 mg/L.

Supporting data is available from two non-GLP publications that were performed according to, or similar to, OECD TG 202. Steudte et al (2012) exposed a total of 25 daphnids (D. magna) per concentration, to several concentrations (and a control) of the test substance for 48 hours under static freshwater conditions in the dark. Bado-Nilles et al (2015) exposed daphnids (D. magna, 20 per concentration) to nominal concentrations that ranged from 47.7 to 500 mg/L, for 48 hours under static conditions in the dark. In both studies, no test concentrations were analytically verified. Immobilisation was recorded after 24 and 48 hours exposure. In both studies, the experiments were conducted twice. Steudte and his group determined the 48-h EC50 to be 860 µM, corresponding to 150 mg/L. Bado-Nilles and colleagues found 48-h EC50 values of 248.5 and 298.4 mg/L, respectively.