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:
11 - 13 Nov 2009
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
guideline study with acceptable restrictions
Remarks:
The study was conducted according to the appropriate OECD test guideline and in compliance with GLP. Test solution described as cloudy grey WAF and effects reported are well above the water solubility of the test substance. No analytical verification was conducted. Thus effects might be overestimated and being physical effects.

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)
Qualifier:
according to
Guideline:
EU Method C.2 (Acute Toxicity for Daphnia)
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent

Sampling and analysis

Analytical monitoring:
no

Test solutions

Vehicle:
no
Details on test solutions:
PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: A stock solution of 100 mg/L was prepared and stirred for 20 hours and left to settle for four hours to produce a cloudy grey water accomodated fraction. The test concentrations were prepared by addition of the appropriate volume of the stock solution using pipettors to test media. They were then made up to the mark in volumetric flasks to give the required concentrations for the test.

Test organisms

Test organisms (species):
Daphnia magna
Details on test organisms:
TEST ORGANISM
- Common name: water flea
- Source: CEFAS Laboratories, Lowestoft
- Age at study initiation (mean and range, SD): less than 24 hours
- Culture conditions: Temperature: 20 ± 2 °C; Dissolved oxygen: >60% ASV; Photoperiod: 16 hours light and 8 hours dark
- Feeding during test: none
- Feeding regime: Each working day, a suspension of Chlorella vulgaris at a rate of 1 mg organic carbon / litre of culture water until 24 hours before the test initiation

Study design

Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
48 h

Test conditions

Test temperature:
20.8 - 21.1 °C
pH:
7.4 - 7.8
Dissolved oxygen:
7.3 - 8.7 mg O2/L
Nominal and measured concentrations:
control, 10, 18, 32, 56 and 100 mg/L (nominal)
Details on test conditions:
TEST SYSTEM
- Test vessel:
- Type (delete if not applicable): closed
- Material, size, headspace, fill volume: 60 mL plastic vessels, filled with 25 mL test solution
- Aeration: before start
- 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: Test and culture medium were the same: reconstituted ISO water with a hardness of 156 mg/L CaCO3. The temperature was adjusted to 18 - 22 °C, aerated until the dissolved oxygen concentration had reached a minimum of 60% air saturation and the pH stabilised between 6 and 9
- Intervals of water quality measurement: pH and dissolved oxygen determinations on pooled replicates for each test and control solution were carried out immediately prior to initiating the test and at the end of the 48 hour test period, temperature was recorded at 0, 24 and 48 hours.

OTHER TEST CONDITIONS
- Adjustment of pH: yes
- Photoperiod: 16 hours light, 8 hours dark

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): immobilisation at 24 and 48 hrs

TEST CONCENTRATIONS
- Range finding study:
Test concentrations: control, 0.1, 1, 10, and 100 mg/L
Results used to determine the conditions for the definitive study: Data identified the 48 hour EC50 as being between 10 and 100 mg/L
Reference substance (positive control):
yes
Remarks:
Potassium dichromate

Results and discussion

Effect concentrationsopen allclose all
Duration:
24 h
Dose descriptor:
EL50
Effect conc.:
74.1 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Remarks on result:
other: 95% CL: 65.1 to 80.3
Duration:
48 h
Dose descriptor:
EL50
Effect conc.:
43.4 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Remarks on result:
other: 95% CL: 40.1 to 44.4
Results with reference substance (positive control):
EC50 (48 h) = 0.27 mg/L

Any other information on results incl. tables

Table 1: Results range-finding test

Exposure period (hours)

Cumulative percentage immobilisation

Concentration mg/L

0

0.1

1

10

100

24

0

0

0

0

5

48

0

0

0

0

5

Table 2: Cumulative immobilisation definitive test

Concentration mg/L

Number immobilised

% immobilisation

24 hours

48 hours

24 hours

48 hours

0

0

0

0

0

10

0

0

0

0

18

0

0

0

0

32

0

1

0

5

56

3

20

15

100

100

20

20

100

100

Table 3: Observations definitive test

Concentration mg/L

Recorded observations

24 hours

48 hours

0

20 NS

20 NS

10

20 NS

20 NS

18

20 NS

20 NS

32

20 NS

2 MS, 17 NS, 1 I

56

17 NS, 3 I

20 I

100

20 I

20 I

MS = movement slower, NS = no signs of abnormalities, I = immobilised

Applicant's summary and conclusion