1H,5H-Pyrazolo(1,2-a)pyrazol-1-one, 2,3-diamino-6,7-dihydro-, dimethanesulfonate

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:

From 04 December 2006 to 28 June 2007

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: compliant to GLP and testing guideline; adequate coherence between data, comments and conclusions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2009

Report date:

2009

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

GLP compliance:

yes

Test material

Reference

Name:

Unnamed

Type:

Constituent

Details on test material:

- Name of test material (as cited in study report): R0054002C, synonym IMEXINE OBH
- Physical state: beige to yellow powder
- Purity: 99.7%
- Impurities (identity and concentrations): not indicated
- Purity test date: 20 July 2006
- Lot/batch No.: R0054002C 013 L 001, synonym 0604070001
- Expiration date of the lot/batch: 01 August 2007
- Stability under test conditions: not indicated
- Storage condition of test material: at room temperature and under nitrogen gas

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

Samples were taken at each test concentration (except for the control) at the beginning of the test and at T24 hours (fresh solutions used for the solution change). Samples were also taken at T24 hours just before the solution change (stale solutions) and at the end of the test at each test concentration (except for the control).

Test solutions

Vehicle:

no

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

Strain: STRAUS-clone 5. Invertebrate crustacean (water flea). Species commonly used in Europe for aquatic toxicity testing and recommended in OECD and EEC guidelines.
origin: Centre Technique du Bois et de l’Ameublement, Paris, France.

Study design

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Test conditions

Hardness:

257 to 264 mg/L as CaCO3

Test temperature:

Between 20.3°C and 21.1°C

pH:

5.92 to 8.21

Dissolved oxygen:

5.8 to 8.8 mg/L

Salinity:

Not measured

Nominal and measured concentrations:

18.8, 37.5, 75.0, 150 and 300 mg/L nominal corresponding respectively to 2.04, 5.24, 21.5, 34.2, 113 and 271 mg/L expressed as geometric means of measured concentrations.

Details on test conditions:

Test solutions were changed after 24 hours.

Test water: reconstituted (M4). The pH of this solution was 8.0 ± 0.5; the sum of Ca and Mg ions in the solution was 2.5 mmol/L (molar ratio Ca:Mg was approximately 4:1 and Na:K approximately 10:1); total hardness was generally between 238 and 289 mg/L as CaCO3.

Temperature in water: between 18°C and 22°C and not varying by more than ± 1°C throughout the test, measured using a max-min thermometer.

Light/dark cycle: 16/8 hours.

Duration of test: 48 hours.

Loading: one daphnid for 10 mL of solution.

pH: between 6± 0.2 and 9± 0.2 in all test item solutions after pH adjustement when relevant ( i.e. < 5.8 or > 9.2) .

Forced aeration: not used during the test. Dilution water was aerated prior to the addition of the test item.

Oxygen concentrations: > 3 mg/L at that temperature.

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

8.49 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

dissolved

Basis for effect:

mobility

Remarks on result:

other: 95% CL48 h: 5.79 - 11.6 mg/L

Effect concentrations 2

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

2.04 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

dissolved

Basis for effect:

mobility

Details on results:

The no observed effect concentration (NOEC) at 48 hours and the highest concentration resulting in no immobilization were 2.04 mg/L, while the 48-hour EC50 of the test item was 8.49 mg/L.

Results with reference substance (positive control):

EC50 24 h (potassium dichromate) = 1.39 mg/L

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

In a 48-hour semi-static acute toxicity test with Daphnia magna, the EC50 (calculated from geometric means of measured concentrations) of IMEXINE OBH was 8.49 mg/L.
The No Observed Effect Concentration (NOEC) was 2.04 mg/L (geometric mean of measured concentrations).