α-(2,4-dichlorophenyl)-1H-imidazole-1-ethanol

Short-term toxicity to aquatic invertebrates

Administrative data

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:

other: Study according to internationally accepted guidelines but not GLP compliant.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

yes

Remarks:

The concentrations of test substance were not analysed in this study. Only nominal concentrations were used.

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

α-(2,4-dichlorophenyl)-1H-imidazole-1-ethanol

EC Number:

246-042-5

EC Name:

α-(2,4-dichlorophenyl)-1H-imidazole-1-ethanol

Cas Number:

24155-42-8

Molecular formula:

C11H10Cl2N2O

IUPAC Name:

1-(2,4-dichlorophenyl)-2-(1H-imidazol-1-yl)ethan-1-ol

Test material form:

solid: crystalline

Details on test material:

Test item: IMIDAZOLE ETHANOL (CAS No. 24155-42-8)
Batch No.: L36066N
Physical state: Light-yellow powder
Active ingredient content (titrimetry): 92.1%
Impurities (HPLC): 9.18%
Storage: 15-30°C

Sampling and analysis

Analytical monitoring:

no

Details on sampling:

The number of immobilised and abnormally behaved daphnids was recorded after 24 and 48 hours.

Test solutions

Details on test solutions:

The test organism was breaded and hold in Elendt M4 medium which was used also for preparing of test item stock and working solutions.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

Test species: Daphnia magna Straus
Age: < 24 hours neonates
Young daphnids were used in the test should have been less than 24 hours old and were not first brood progeny.
Source: National Institute of Environmental Health

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Test conditions

Test temperature:

21 (±1) °C

pH:

The pH was measured at the beginning and the end of the test. The pH of test solutions was not adjusted at the beginning of the test

Dissolved oxygen:

The dissolved oxygen was measured at the beginning and the end of the test in the control and the group with the highest test substance concentration

Nominal and measured concentrations:

The following concentrations were applied: 0.69; 1.38; 2.76; 5.52; 11.05; 22.10 and 44.20 mg/l.
The evaluation of toxic effect was based on the nominal concentrations of test item which were modified by correction factor.

Details on test conditions:

At each concentration level four replicates were used. Each replicate contained 5 daphnids in 50 ml test solution. The test vessels were covered with plastic lid and were kept in thermostat at 21 ± 1 °C with a 16/8 hours light/dark cycle. The treatment of control vessels was same as test vessels.
The pH and oxygen concentrations were measured at the beginning and at the end of test. The numbers of immobilised daphnids were counted at 24 and 48 hours after the start of test.

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

48 h

Dose descriptor:

EC10

Effect conc.:

3.899 mg/L

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% CL

Effect concentrations 2

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

8.953 mg/L

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% CL

Details on results:

The statistical analyses of data were performed by ToxRat® software.
The NOEC and LOEC were determined with Fisher’s exact binominal test with Bonferroni correction. The results were inconclusive.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

In this Daphnia magna, Acute Immobilisation Test for “Imidazole Ethanol” (CAS No. 24155-42-8) the results indicated that the test item is hazardous to the aquatic environment [GHS Acute aquatic hazard Category Acute 2. – 48 hr EC50 (for Crustacea) > 1 ≤ 10 mg/l]