Registration Dossier

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
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Non-GLP guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1993
Report date:
1993

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
EU Method C.3 (Algal Inhibition test)
GLP compliance:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): D-Milchsäureisobutylester
- Physical state: fluid
- Analytical purity: 99%
- Impurities: i-Butanol (< 1%)
- Batch No.: Cont. TTTU 119 618

Sampling and analysis

Analytical monitoring:
no

Test solutions

Vehicle:
no

Test organisms

Test organisms (species):
Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)
Details on test organisms:
TEST ORGANISM
- Common name: green alga
- Strain: SAG 86.81
- Source: Collection of algal cultures in Goettingen, Germany

METHOD OF CULTIVATION
Stock culture
- Culture vessel: 250 ml Erlenmeyer flask
- Culture volume: 100 ml
- Initial cell density: 10000 cells/ml
- Growth period: weekly passage

Pre culture
- Culture vessel: 250 ml Erlenmeyer flask
- Culture volume: 100 ml
- Initial cell density: 10000 cells/ml
- Groth period: 72 h

Test culture
- Culture vessel: glas tubes with flat bottom
- Culture volume: 8 ml
- Initial cell density: 10000 cells/ml
- Groth period: 72 h


Study design

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

Test conditions

pH:
uninoculated: 8.0 - 8.9
inoculated: 8.1 - 9.5
Nominal and measured concentrations:
Nominal test concentrations: control, 0.78, 1.56, 3.13, 6.25, 12.5, 25, 50, 100 mg/l
Details on test conditions:
TEST SYSTEM
_ Initial cells density: 10000 cells/ml
- No. of vessels per concentration (inoculated): 4
- No. of vessels per control (inoculated): 4

GROWTH MEDIUM
- Standard medium used: yes

TEST MEDIUM / WATER PARAMETERS
- Intervals of water quality measurement: pH after 0 h in a uninoculated replicate and after 72 h in a uninoculated and inoculated replicate

OTHER TEST CONDITIONS
- Photoperiod: permanent light
- Light intensity and quality: universal white, 120 µE/m²s

EFFECT PARAMETERS MEASURED:
- Determination of cell concentrations: Neubauer improved
- Chlorophyll measurement: fluoreszence

Results and discussion

Effect concentrationsopen allclose all
Duration:
72 h
Dose descriptor:
EC10
Effect conc.:
36 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:
growth rate
Duration:
72 h
Dose descriptor:
EC90
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Duration:
72 h
Dose descriptor:
EC10
Effect conc.:
13 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:
biomass
Duration:
72 h
Dose descriptor:
EC90
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
biomass

Applicant's summary and conclusion