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: Guideline study, however toxic effects range outside the water solubility of the test substance. Furthermore acetone was used as solubiliser, no analytical monitoring.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1981
Report Date:
1981

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
other: German standard test guideline, DIN 38 412 part 9
GLP compliance:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): Retinyl palmitate
- Lot/batch No.: 8587
Purity: no data given

Sampling and analysis

Analytical monitoring:
no

Test solutions

Vehicle:
yes
Details on test solutions:
PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: The stock solution was prepared by dissolving 162.0 mg/l test substance and 200 mg/l of the solubiliser acetone in dilution water. The test concentrations were then prepared by dilution with test water.

Test organisms

Test organisms (species):
Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)
Details on test organisms:
TEST ORGANISM
- Strain: SAG 86.81

Study design

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

Test conditions

Test temperature:
24 +/- 1 °C
Nominal and measured concentrations:
Nominal test concentrations:
2.38,
4.29,
7.72,
13.89,
25.00,
45.00,
81.00,
control
Details on test conditions:
TEST SYSTEM
- Test vessel: Erlenmeyer flask (nominal volume 250 ml)
- Aeration:
- Type of flow-through (e.g. peristaltic or proportional diluter):
- Renewal rate of test solution (frequency/flow rate):
- Initial cells density:
- Control end cells density: 10000
- No. of organisms per vessel:
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
- No. of vessels per vehicle control (replicates):


GROWTH MEDIUM
- Standard medium used: yes/no
- Detailed composition if non-standard medium was used:


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: according to DIN 38412, part 9
- Total organic carbon:
- Particulate matter:
- Metals:
- Pesticides:
- Chlorine:
- Alkalinity:
- Ca/mg ratio:
- Conductivity:
- Culture medium different from test medium:
- Intervals of water quality measurement:


OTHER TEST CONDITIONS
- Sterile test conditions: yes/no
- Adjustment of pH:
- Photoperiod:permanent illumination
- Light intensity and quality: artificial light, about 120 microE/(m2*s)
- Salinity (for marine algae):


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: fluorimeter after 0, 24, 48 and 72 h
- Chlorophyll measurement:
- Other:


TEST CONCENTRATIONS
- Spacing factor for test concentrations:
- Justification for using less concentrations than requested by guideline:
- Range finding study
- Test concentrations:
- Results used to determine the conditions for the definitive study:

Results and discussion

Effect concentrationsopen allclose all
Duration:
72 h
Dose descriptor:
LOEC
Effect conc.:
2.38 mg/L
Nominal / measured:
nominal
Conc. based on:
act. ingr.
Basis for effect:
growth rate
Duration:
72 h
Dose descriptor:
EC10
Effect conc.:
4.44 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
152.94 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate

Any other information on results incl. tables

During the 72 h exposure to Retinyl palmitate following growth rate was  detected (average of 4 replicates)*:

Nominal test / growth / growth
concentration / rate / inhibition [%]
(mg/l)
Control / 1.01 / 4.90
solvent ctrl. / 1.06 / n. d.
2.38 / 0.97 / 7.83
4.29 / 0.95 / 10.16
7.72 / 0.92 / 12.61
13.89 / 0.90 / 14.77
25.00 / 0.79 / 25.59
45.00 / 0.82 / 22.12
81.00 / 0.48 / 54.30


*10000 cells/ml were introduced at the test start.


ECx values (in mg/l) after 72 hours of exposure (biomass)
EC10 / 2.44

EC50 / 25.57

EC90 / 267.52

Applicant's summary and conclusion