Retinyl propionate

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

Guideline:

other: German standard test guideline, DIN 38 412 part 9

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Retinyl palmitate

EC Number:

201-228-5

EC Name:

Retinyl palmitate

Cas Number:

79-81-2

IUPAC Name:

O~15~-palmitoylretinol

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 concentrations

Effect concentrations 1

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

Effect concentrations 2

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

Effect concentrations 3

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