[No public or meaningful name is available]

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:

05-Oct-2010 to 10-Nov-2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: This study has been performed according to OECD and EC guidelines and according to GLP principles

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

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 (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

No. 338 RED

IUPAC Name:

No. 338 RED

Details on test material:

- Substance type: red powder
- Lot/batch No.: 00004

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: all concentrations and control
- Sampling method: 3 ml from the approximate centre of the test vessels at t=0 and t=48 h
- Sample storage conditions before analysis: Samples were stored in a freezer until analysis

Test solutions

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- method: All test solutions were individually prepared. Preparation included three days of magnetic stirring in the dark followed by filtration through a 0.45 μm membrane filter (Whatman, RC55) to remove the remaining undissolved material. The final test solutions were all clear and increasingly pink/red with increasing concentration.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna (Crustacea, Cladocera) (Straus, 1820)
- Source: In-house laboratory culture with a known history.
- Age at study initiation: < 24 hours
- Method of breeding: With newborn daphnids, i.e. less than 3 days old, by placing about 250 of them into 10 litres of medium in an all-glass culture vessel.
- Feeding during test: No

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test conditions

Hardness:

180 mg/l expressed as CaCO3

Test temperature:

Between 19.0 and 20.2°C

pH:

Between 8.0 and 8.2

Dissolved oxygen:

Between 8.5 and 8.9 mg/l

Nominal and measured concentrations:

Nominal: loading rates of 4.6, 10, 22, 46 and 100 mg/l (5 µm filtered solutions)
Measured: 2.59, 6.11, 13.9, 20.1 and 23.7 mg/l in the filtered solutions prepared at 4.6, 10, 22, 46 and 100 mg/l, respectively. During the exposure period the measured concentrations remained stable at > 90% of initial. Consequently, all results were based on the initial measured concentrations.

Details on test conditions:

- Type (delete if not applicable): open
- Material, size, headspace, fill volume: glass, 100 ml, normal headspace, 80 ml
- Aeration: no
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Adjusted ISO medium: the following chemicals (analytical grade) are dissolved in tap water purified by Reverse Osmosis (RO-water, GEON Waterbehandeling, Berkel-Enschot, The Netherlands):
Macro salts:
CaCl2.2H2O : 211.5 mg/l
MgSO4.7H2O: 88.8 mg/l
NaHCO3 : 46.7 mg/l
KCl : 4.2 mg/l
The hardness: 180 mg/l expressed as CaCO3 and the pH: 7.7 ± 0.3 after aeration.
- Culture medium different from test medium: yes, for culturing M7 medium is used
OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 hours photoperiod daily
EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : EC50 t=24, 48 h and NOEC
TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2.2
- Test concentrations:control and 0.45 µm filtered solutions prepared at loading rates of 4.6, 10, 22, 46 and 100 mg/l

Reference substance (positive control):

yes

Remarks:

potassium dichromate (K2Cr2O7)

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

6.1 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 2

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

21.6 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 17.8-28.6 mg/l

Effect concentrations 3

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

14 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 12.3-16.7 mg/l

Details on results:

Behavioural abnormalities: no
- Immobility of control: no immobility was observed.
- Other adverse effects control: no

Results with reference substance (positive control):

- Results with reference substance valid? yes

The 24h-EC50 was 0.52 mg/l with a 95% confidence interval between 0.48 and 0.60 mg/l.

The 48h-EC50 was 0.38 mg/l with a 95% confidence interval between 0.34 and 0.45 mg/l.

Reported statistics and error estimates:

Calculation of EC50:

The EC50-value was calculated at 24 and 48 hours of exposure from the probits of the percentages of affected daphnids and the logarithms of the corresponding test substance concentrations using the maximum likelihood estimation method (Finney, D.J., 1971: Probit analysis, Cambridge University Press, Cambridge, U.K., 3rd edition).

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The test substance did not induce acute immobilisation of Daphnia magna at 6.1 mg/l after 48 hours of exposure (NOEC).

The 48h-EC50 was 14.0 mg/l based on initial measured concentrations (95% confidence interval between 12.3 and 16.7 mg/l).