4-methylpyrazole

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP compliant guideline study, available as unpublished report, no restrictions, fully adequate for assessment

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1997

Report date:

1997

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

4-methylpyrazole

EC Number:

231-445-0

EC Name:

4-methylpyrazole

Cas Number:

7554-65-6

Molecular formula:

C4H6N2

IUPAC Name:

4-methyl-1H-pyrazole

Details on test material:

- Name of test material (as cited in study report): 4-Methylpyrazol
- Physical state: liquid, yellowish

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

At the start of the test (after 0 hours) samples from vessels which were not stocked with daphnids were analysed and at the end of the test (after 48 h) samples from stocked and unstocked vessels were analysed.

Test solutions

Details on test solutions:

For the preparation of the stock solution the test substance was stirred for about 10 minutes at 22 ±1 °C in M4-medium. The nominal concentration of the stock solution was 100 mg/L.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Strain: STRAUS
- Source: Institut National de Recherche Chimique Appliquée, France
- Method of breeding: cultured under standard conditions in the laboratory

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test conditions

Hardness:

2.20 - 3.20 mmol/L (CaCO3)

Test temperature:

20-21.3 °C

pH:

8.0-8.2

Dissolved oxygen:

8.0-8.2 mg/L

Nominal and measured concentrations:

12.5, 25, 50, 100 mg/L (nominal)
Recovery by analysis: 77.6-104%

Details on test conditions:

- Duration of the test: 48 hours
- Test temperature: 20 ± 2 °C
- Test vessels: Test tubes (glass) with flat bottom (Nominal volume 20 mL)
- Test volume: 10 mL
- Loading (animals/mL): 0,5
- Number of animals/vessel: 5
- Total number of animals/conc: 20
- Number of replicates/conc: 4
- Number of replicates/control: 4
- Age of the animals at the start of the test: 2 - 24 hours
- Age of stock animals: 2 - 4 weeks
- Illumination: Artificial Iight, OSRAM L58 W31 warm white
- day : night-rhythm = 16 : 8 hours
- Light intensity: About 5 - 6 µE/(m2s) in the range of 400 - 700 nm
- Test parameter: Swimming ability of the test animals
- Check of the study and recording (swimming ability) : Visually, after 0, 3, 6, 24 and 48 h
- Feeding: None
- Measurement of temperature: After 0, 24, 48 h in an extra vessel close to the test vessels
- Measurement of pH and oxygen: After 0 and 48 h in one replicate at each concentration

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 2

Duration:

48 h

Dose descriptor:

EC0

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Reported statistics and error estimates:

Due to the results of the test a statistical evaluation of the data was unnecessary.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes