m-(4,5-dihydro-3-methyl-5-oxo-1H-pyrazol-1-yl)benzenesulphonic acid

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

Study period:

April 1991

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study followed international Guidelines, no deviations are reported. The experiment is well documented.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1991

Report date:

1991

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Version / remarks:

as of November 1989

Deviations:

not specified

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

m-(4,5-dihydro-3-methyl-5-oxo-1H-pyrazol-1-yl)benzenesulphonic acid

EC Number:

204-303-0

EC Name:

m-(4,5-dihydro-3-methyl-5-oxo-1H-pyrazol-1-yl)benzenesulphonic acid

Cas Number:

119-17-5

Molecular formula:

C10H10N2O4S

IUPAC Name:

3-(3-methyl-5-oxo-4,5-dihydro-1H-pyrazol-1-yl)benzene-1-sulfonic acid

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

no

Details on test solutions:

- Fresh stock solution was freshly prepared at the beginning of the study
- A specified amount of test substance was weighed directly into the dilution water
- Concentration of the stock solution was adjusted to 100 mg/L
- The following concentrations were prepared out of the stock solution: 100 mg/L, 50 mg/L, 25 mg/L, 12.5 mg/L

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

- 2 animals per mL
- 5 animals per vessel
- 20 animals per concentration
- Age of the animals at the beginning of the study: 2 - 24 h
- Age of the parents of the test animals: 2 - 4 weeks
- No feeding during study
- 16 hrs night / 8 hrs day

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test conditions

Hardness:

2.7 +/- 0.5 mmol/L

Test temperature:

21.3 - 21.5 °C

pH:

6.5 - 8.0

Dissolved oxygen:

7.8 - 8.7 mg/L

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

48 h

Dose descriptor:

EC0

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: immobilisation

Effect concentrations 2

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: immobilisation

Effect concentrations 3

Duration:

48 h

Dose descriptor:

EC100

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: immobilisation

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Based on this result the test item is not subject for classification as toxic for daphnia

Executive summary:

Acute toxicity of pyracolic acid-3 to Daphnia magna was assessed in an immobilisation assay according to 79/831/EEC, Method C2 (as of November 1989). The test substance was tested in a concentration range of 12.5 mg/L to 100 mg/L (nominal), with a spacing factor of 2.

As a substitute for mortality, immobilisation is used as an endpoint after 48 hrs. The result is displayed as effect concentration (EC).

The following results were obtained:

EC0 (48 hrs):            100 mg/L

EC50 (48 hrs):       > 100 mg/L

EC100 (48 hrs):     > 100 mg/L

The test fulfilled the validation criteria.