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
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2003
Report Date:
2003

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: crystalline

Sampling and analysis

Analytical monitoring:
no

Test solutions

Vehicle:
no
Details on test solutions:
Test solution were prepared by adding a 100 mg/l stock solution (preapared by direct addition of the test material to water, with stirring) to diution water in appropriate quantities to obtain the desired test concentrations.

Test organisms

Test organisms (species):
Daphnia magna
Details on test organisms:
TEST ORGANISM
- Common name: Daphnia magna
- Source: Reading University
- Age of parental stock (mean and range, SD): Less 24h at start of test
- Feeding during test: no
- Food type: prior to testing, a suspension of Chlorella vulgaris
- Amount: 1mg organic carbon per litre of culture water
- Frequency: each working day


Study design

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

Test conditions

Hardness:
231 mg/L CaCO3
Test temperature:
20 +/- 1°C
pH:
7.2 +/- 0.2
Dissolved oxygen:
minimum 60%
Nominal and measured concentrations:
Nominal: 0, 10, 18, 32, 56, 100 mg/L
Details on test conditions:
TEST SYSTEM
- Test vessel: 50 mL crystalline dishes
- Type: open - transparent perspex sheet was placed on top of dishes
- Material, size, headspace, fill volume: glass, 25mL
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16h light, 8h dark


RANGE-FINDING STUDY
- Test concentrations: 0, 0.32, 1.0, 3.2, 10, 32, 100 mg/L
- Results used to determine the conditions for the definitive study: yes
Reference substance (positive control):
yes
Remarks:
Potassium dichromate

Results and discussion

Effect concentrationsopen allclose all
Duration:
24 h
Dose descriptor:
EC50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Key result
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Details on results:
Two main studies conducted as the results of the first main study (no immobility in any test concentration was seen) was not expected based on the results of the preliminary study. Both main studies gave the same results EC50 >100 mg/L.
Results with reference substance (positive control):
- Results with reference substance valid? yes
- Relevant effect levels: 48h EC50 0.8 mg/L

Any other information on results incl. tables

Table 1: Preliminary range finding study - cumulative % immobilisation

 Concentration (mg/L)        No. immobilised % immobilisation
 24 hours  48 hours  24 hours  48 hours
 0  0  1  0  20
 0.32  0  1  0  20
 1.0  0  1  0  20
 3.2  1  1  20  20
 10  0  1  0  20
 32  2  3  40  60
 100  2  5  40  100

Table 2: First main study - cumulative % immobilisation

Concentration (mg/L)        No. 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  0  0  0
 56  1  1  5  5
 100  0  0  0  0

Table 3 - Second main study - culumative % immobilisation

Concentration (mg/L)        No. 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  0  0  0
 56  0  0  0  0
 100  0  0  0  0

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
The 48h EC50 value for the test substance was >100mg/L.