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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:
other: GLP-study according to guideline

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2001
Report Date:
2002

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)
Version / remarks:
1984
Deviations:
no
Qualifier:
according to
Guideline:
EU Method C.2 (Acute Toxicity for Daphnia)
Version / remarks:
1992
Deviations:
no
GLP compliance:
yes (incl. certificate)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Specific details on test material used for the study:
Details on properties of test surrogate or analogue material (migrated information):
- Water solubility (under test conditions): not applicable, hydrolysis
- Stability in water: hydrolysis




- Results of test for ready biodegradability: not ready biodegradable

Sampling and analysis

Analytical monitoring:
yes
Details on sampling:
For stability control a series of the concentrations tested, was made up in the same way as the concentrations for biological part, but in separate vessels without test organisms ans NaHCO3
Sampling time : 0 and 48h

Test solutions

Vehicle:
no
Details on test solutions:
For stock solution, 1.1 ml of the test item were mixed with 1000 mL synthetic fresh water without NaHCO3 for about 1h in an open vessel under a laboratory hood and than the vessel was closed. The resulting solution served as stock solution with a measured analytical value of 420 mg TOC/L resp. 793 mg test item/L

Test organisms

Test organisms (species):
Daphnia magna
Details on test organisms:
TEST ORGANISM
- Common name: Daphnia magna
- Strain: Strauss clone 5
- Source: inhosue breeding (origined from Bayer AG, 1991)
- Age at study initiation (mean and range, SD): 24h
- Method of breeding: females maintained in M4 medium in 1L beakers, at two to three day intervals, teh excuviae are sphoned off and the water is changed, offspring is removed from the breeding vessels; in a four week interval, offspring is isolated from the vessel and serve as a basis for further breeding
- Feeding during test
no


ACCLIMATION
- Acclimation period: 24h in synthetic water

Study design

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

Test conditions

Hardness:
14°dH
Test temperature:
20 +- 1°C
pH:
begin of the test: control: 8.1, concentration dependent decrease of a pH with 8.1 (2.77 mg/L) down to 3.9 at 79.3 mg/L
end of the test: control: 7.8, concentration dependent decrease with 7.4 (2.77 mg/L) down to 4.0 (79.3 mg/L), no major difference for the two endpoints measured
Dissolved oxygen:
Begin of the test: 7.7-8.1
End of the test: 7.8-8.7
Salinity:
no
Nominal and measured concentrations:
measured test concentrationss (DOC) after 48h ranges from 87-101% compared to the initial DOC values, therefore, the bological values were calculated with the nominal concentrations
Details on test conditions:
TEST SYSTEM
- Test vessel:
- Type: closed (gas tight septum)
- Material, size, headspace, fill volume: 22 mL head-space test tubes volume inside the test vessel was increased to 20 mL resulting in a reduced gas phase
- Aeration: no
- No. of organisms per vessel: 5 organisms
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: not reported
- Ca/mg ratio: 4:1
- Na/K ratio: 10:1

- Culture medium different from test medium: no



OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: dark
- Light intensity: not applicable


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :


TEST CONCENTRATIONS
- Spacing factor for test concentrations:
- Justification for using less concentrations than requested by guideline:
- Range finding study: no details reported in the final report
Reference substance (positive control):
yes
Remarks:
potassium dichromate

Results and discussion

Effect concentrationsopen allclose all
Duration:
24 h
Dose descriptor:
LC50
Effect conc.:
61 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Remarks on result:
other: not given
Duration:
48 h
Dose descriptor:
LC50
Effect conc.:
42 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Remarks on result:
other: not given
Duration:
48 h
Dose descriptor:
LC0
Effect conc.:
28 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Details on results:
- Mortality of control: no
- Other adverse effects control: no
- Abnormal responses: no
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: no
- Effect concentrations exceeding solubility of substance in test medium: no
- The high toxicity at the highest concentration may be due to the low pH level (3.9-4.0)
Results with reference substance (positive control):
- Results with reference substance valid? yes
- Mortality: yes
- EC50/LC50: 1 mg/L < 50% effect, 2 mg/L >50% effect
- Other: Reference item was tested quartely
Reported statistics and error estimates:
Due to the strong dose-response relationship, the EC50 values after 24h and 48h were calculated graphically.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
Under conditions tested , the LC50 value after 48h of test item and its hydrolysis products is 42 mg/L. The toxicity observed can be regarded as pH effects (pH < 6.2 at concentrations >= 47.6)