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Ecotoxicological information

Toxicity to aquatic algae and cyanobacteria

Administrative data

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2006-11-12 to 2007-02-15
Reliability:
1 (reliable without restriction)

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2007

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 201 (Alga, Growth Inhibition Test)
Deviations:
yes
Principles of method if other than guideline:
no analytical determination of the content of the test item in the tests solutions during the test was made
GLP compliance:
yes (incl. certificate)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): IUPAC name
- Physical state: solid
- Analytical purity: >99%
- Lot/batch No.: T62435
- Expiration date of the lot/batch: 09/06/14
- Stability under test conditions: water 96h
- Storage condition of test material: room temperature 20+-5°C
Specific details on test material used for the study:
Details on properties of test surrogate or analogue material (migrated information):
PHYSICO-CHEMICAL PROPERTIES
- Melting point: 70-80°C
- Boiling point: >300°C
- Vapour pressure: at 25°C 6.66 x 10-5 Pa
- Water solubility (under test conditions): <1mg/L
- log Pow: 9.7
- Stability in water: <1mg/L



OTHER PROPERTIES (if relevant for this endpoint)
- Results of test for ready biodegradability: ready biodegradable

Sampling and analysis

Analytical monitoring:
yes

Test solutions

Vehicle:
no
Details on test solutions:
all solutions were sterilised before use

Test organisms

Test organisms (species):
Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)
Details on test organisms:
TEST ORGANISM
- Common name: desmodesmus subspicatus
- Strain: CHODAT
- Source (laboratory, culture collection): laboratory
- Age of inoculum (at test initiation): 24h



ACCLIMATION
- Acclimation period:72h

Study design

Test type:
static
Water media type:
freshwater
Limit test:
yes
Total exposure duration:
72 h
Post exposure observation period:
After every 24 hours the cell concentration was measured with a spectral photometer

Test conditions

Test temperature:
21-24°C
pH:
8.1-10.1
Nominal and measured concentrations:
1;10;100 mg/L
Details on test conditions:
TEST SYSTEM
- Test vessel:
- Type (delete if not applicable): round cuvette
- Material, size, headspace, fill volume: d=6mm
- Initial cells density: 10 000 CFU/ml
- Control end cells density:
- No. of organisms per vessel:10000/ml
- No. of vessels per concentration (replicates):3
- No. of vessels per control (replicates):6



GROWTH MEDIUM
- Standard medium used: yes

OTHER TEST CONDITIONS
- Sterile test conditions: yes
- Adjustment of pH:8.1-10.1
- Light intensity and quality:4440-8880 lux



EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations:spectrophotometer

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 10
- Range finding study
- Test concentrations: 1;10;100mg/L
- Results used to determine the conditions for the definitive study:result of Water accommodated Fraction
Reference substance (positive control):
yes
Remarks:
potassium dichromate

Results and discussion

Effect concentrationsopen allclose all
Duration:
72 h
Dose descriptor:
NOEC
Effect conc.:
ca. 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Duration:
72 h
Dose descriptor:
NOEC
Effect conc.:
ca. 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
cell number
Duration:
72 h
Dose descriptor:
NOEC
Effect conc.:
ca. 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
biomass
Duration:
72 h
Dose descriptor:
LOEC
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Duration:
72 h
Dose descriptor:
LOEC
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
cell number
Duration:
72 h
Dose descriptor:
LOEC
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
biomass
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
cell number
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
biomass
Results with reference substance (positive control):
- Results with reference substance valid
- 72h-NOEC=0.1mg/L
-72h-LOEC=0.16mg/L
-72h-ECr50=1.1mg/L
-72h-ECb50=0.36mg/L
-72h-ECy50=0.30mg/L

Any other information on results incl. tables

As the test item is poorly soluble in water, the Water accommodated fraction was tested. This was done by shaking the nominal Load with the appropriiate amount of deionised water for 24 hours , followed by memenrane filtration.

In the main study , three concentrations of the test item in a geometric series (spaced by factor 10, the highest being 100mg/L) were used. The treatments were used to incubate the unicellular freshwater green alga Desmodesmus subspicatus for a period of 72 hours.

The cell concentration of each replicate was determined by measuring the absorption of the cuvettes at 440 nm every 24 hours with a spectral photometer. With these measured values, the number of cells was calculated (linear correlation between cell concentration and absorption given). Then the growth rate, the area under the growth curve (AUC) and the yield could be determined.

The EC50s of potassium dichromate was tested in acurrent reference test. the values lay within the normal range of the laboratory.

The following results for the test item Montanov 202 were determined.

72h NOEC (Growth Rate)= 100 mg/L

72h NOEC (AUC)= 100mg/L

72h NOEC (Yield) = 100mg/L

72h LOEC (Growth Rate)>100 mg/L

72h LOEC (AUC)>100mg/L

72h LOEC (Yield)>100 mg/L

72h ECr50>100mg/L

72h ECb50 >100 mg/L

72h ECy50 >100 mg/L

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
The following results for the test item Montanov 202 were determined.

72h NOEC (Growth Rate)= 100 mg/L

72h NOEC (AUC)= 100mg/L

72h NOEC (Yield) = 100mg/L


72h LOEC (Growth Rate)>100 mg/L

72h LOEC (AUC)>100mg/L

72h LOEC (Yield)>100 mg/L


72h ECr50>100mg/L

72h ECb50 >100 mg/L

72h ECy50 >100 mg/L
Executive summary:

As the test item is poorly soluble in water, the Water accommodated fraction was tested. This was done by shaking the nominal Load with the appropriate amount of deionised water for 24 hours , followed by memenrane filtration.

In the main study , three concentrations of the test item in a geometric series (spaced by factor 10, the highest being 100mg/L) were used. The treatments were used to incubate the unicellular freshwater green alga Desmodesmus subspicatus for a period of 72 hours.

The cell concentration of each replicate was determined by measuring the absorption of the cuvettes at 440 nm every 24 hours with a spectral photometer. With these measured values, the number of cells was calculated (linear correlation between cell concentration and absorption given). Then the growth rate, the area under the growth curve (AUC) and the yield could be determined.

The EC50s of potassium dichromate was tested in acurrent reference test. the values lay within the normal range of the laboratory.

The following results for the test item Montanov 202 were determined.

72h NOEC (Growth Rate)= 100 mg/L

72h NOEC (AUC)= 100mg/L

72h NOEC (Yield) = 100mg/L

72h LOEC (Growth Rate)>100 mg/L

72h LOEC (AUC)>100mg/L

72h LOEC (Yield)>100 mg/L

72h ECr50>100mg/L

72h ECb50 >100 mg/L

72h ECy50 >100 mg/L