Registration Dossier

Ecotoxicological information

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:
22 - 24 Apr 2009
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
guideline study with acceptable restrictions
Remarks:
Due to the nature of the test item, analytical measurement is not possible.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2009
Report Date:
2009

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)
Version / remarks:
OECD 2004
Deviations:
no
Qualifier:
according to
Guideline:
other: OECD guidance document no 23, Aquatic Toxicity Testing of Difficult Substances
Deviations:
no
Qualifier:
according to
Guideline:
EU Method C.2 (Acute Toxicity for Daphnia)
Deviations:
no
GLP compliance:
yes (incl. certificate)
Remarks:
THE DEPARTMENT OF HEALTH OF THE GOVERNMENT OF THE UNITED KlNGDOM, UK GLP Monitoring Authority

Test material

Reference
Name:
Unnamed
Type:
Constituent

Sampling and analysis

Analytical monitoring:
no
Remarks:
Due to the nature of the test item, analytical measurement is not possible.

Test solutions

Vehicle:
no
Details on test solutions:
PREPARATION AND APPLICATION OF TEST SOLUTION
- Differential loading:
Since a limittest was conducted the only test item concentration was 100 mg/L. For each nominal concentration the required amount of homogenized sample was added to 500 mL of culture medium in an aspirator. The aspirators were mixed for 48 h at 21 to 23 °C and then allowed to separate for four hours. The aqueous phase, avoiding all settled and floating material, was drawn off and filtered using Whatman No. 1 filter paper. The resultant solution was used as the test exposure solution.
- Controls: medium without test item

Test organisms

Test organisms (species):
Daphnia magna
Details on test organisms:
TEST ORGANISM
- Common name: Water flea
- Source: CEFAS Laboratories, Lowestoft
- Feeding during test: No feeding durinng the test

ACCLIMATION
- Acclimation conditions (same as test or not): same; the water was adjusted to 18 - 22 °C, aerated until the dissoved oxygen concentration had reached a minimum of 3 mg/L and pH stabilised between 6 and 9.
- Type and amount of food: A suspension of Chlorella vulgaris. 1 mg/L organic carbon/litre of culture water until 24 h before the test initiation.
- Feeding frequency: each working day

METHOD FOR PREPARATION AND COLLECTION OF EARLY INSTARS OR OTHER LIFE STAGES: Less than 24 h

Study design

Test type:
static
Water media type:
freshwater
Limit test:
yes
Total exposure duration:
48 h

Test conditions

Test temperature:
20.0 (Control and 100 mg/L)
pH:
8.0 - 7.5 (Control)
7.3 - 7.2 (100 mg/L)
Dissolved oxygen:
7.6 - 10.0 (Control)
8.8 - 9.6 (100 mg/L)
Nominal and measured concentrations:
Control and 100 mg/L (nominal loading rate)
Details on test conditions:
TEST SYSTEM
Test vessel:
- Type: open (covered with a transparent perspex sheet over the tops of the dishes to reduce evaporation)
- Material, size, headspace, fill volume: 60 mL glass beaker, 25 mL test volume, 35 mL headspace, to limit the aerial contamination of the test vessels and reduce evaporation losses, a transparent perspex sheet was placed over the tops of the dishes.
- 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: reconstituted ISO water
- Culture medium different from test medium: Culture medium and test medium the same
- Intervals of water quality measurement: Water qualities , pH and dissolved oxygen determinations, on pooled replicates for the test and control solution were carried out immediately prior to initiating the test and at the end of the 48 h test period, temperature was recorded at 0, 24 and 48 h.

OTHER TEST CONDITIONS
- Photoperiod: 16 h light and 8 h dark

EFFECT PARAMETERS MEASURED: The number of immobilised Daphnia was recorded after 24 and 48 h h periods.

RANGE-FINDING STUDY
- Test concentrations: 0, 0.1, 1.0, 10 and 100 mg/L
- Results used to determine the conditions for the definitive study: No Daphnia was immobile up to and including 100 mg/L after 48 h.
Reference substance (positive control):
yes
Remarks:
Potassium dichromate

Results and discussion

Effect concentrations
Duration:
48 h
Dose descriptor:
EL50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Details on results:
- Behavioural abnormalities: No abnormal behaviour was observed.
- Mortality of control: No mortality was observed.
Results with reference substance (positive control):
- EC50: 0.88 mg/L (95% confidential limit: 0.76 - 1.03 mg/L)
Reported statistics and error estimates:
Where possible the EL50 values are shown graphically with calculated with 95% confidence limits according to the methods of ToxCalc tm Version 5.0 "Comprehensive Toxicity Data Analysis and Database Software"

Any other information on results incl. tables

Biological results:

The 48 h EL50 value of the test item to Daphnia magna was estimated to be greater than 100 mg/L. The highest no observed effect loading rate (NOELR) after 48 h was 100 mg/L.

Table 1: Cumulative immobilisation

Loading rate

Number immobilized

% Immobilisation

[mg/L]

24 h

48 h

24 h

48 h

0

0

0

0

0

100

0

0

0

0

 Table 2: Observation:

Loading rate

Recorded observations

 

 

[mg/L]

24 h

48 h

0

NS

NS

100

NS

NS

NS no signs of abnormal behavior

Table 3: EL50 and NOELR values (based on the nominal loading rate)

Period of exposure (h)

EL50 value

95% confidence limits

NOELR

0

> 100 mg/L

Not possible to determine

100 mg/L

100

> 100 mg/L

Not possible to determine

100 mg/L

Table 4: Validity criteria

Criterion from the guideline

Outcome

Validity criterion fulfilled

In the control, including the control containing the solubilising agent, not more than 10% of the daphnids should have been immobilized.

no immobile Daphnia was observed

Yes

The dissolved oxygen concentration at the end of the test should be ≥ 3 mg/L in control and test vessels.

Oxygen concentration was ≥ 3 mg/L

Yes

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Remarks:
For further details please refer to “Any other information on results incl. tables”.