Fatty acids, vegetable-oil, Me esters, sulfurized

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:

FROM 29 AUG 2018 TO 30 NOV 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

yes

Remarks:

The temperature in the experiment was in the range 21.8 – 24.5°C, and therefore not in the desired range and fluctuated by more than ± 2°C. The stock solutions to be autoclaved were autoclaved for 20 min. instead of the required 15 min.

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Fatty acids, vegetable-oil, Me esters, sulfurized

EC Number:

276-337-4

EC Name:

Fatty acids, vegetable-oil, Me esters, sulfurized

Cas Number:

72102-30-8

IUPAC Name:

Fatty Acids, vegetable-oil, Me-Esters, sulfurized

Test material form:

liquid

Details on test material:

- Density: 0.95 g/mL
- Batch no.: 71012767

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 100 mg/L nominal concentration

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: The water-accommodated fraction (WAF) was prepared for the test. This was done by mixing 99.8 mg/L resp. 105 μL/L test item (based on a density of 0.95 g/mL stated in the SDS) with the corresponding amount of algal medium (demineralised water enriched with minerals but without algae) and stirring moderate for 24 hours 15 minutes. The lower phase was used unfiltered as test solution.
- Controls: At the start and at the end of the test, the content of the test item in the test solutions was determined using GC/MSD.
- Evidence of undissolved material (e.g. precipitate, surface film, etc.): not stated

Test organisms

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

TEST ORGANISM
- Common name: Desmodesmus subspicatus
- Strain: SAG Strain Number 86.81
- Source (laboratory, culture collection): MBM Sciencebridge GmbH (Institut für Pflanzenphysiologie of Universität Göttingen) in January 2016

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

72 h

Test conditions

Test temperature:

21.8 – 24.5°C

pH:

Nominal Concentration in mg/L 0 h 72 h
Blank control 7.5 9.0
100 7.5 9.5

Nominal and measured concentrations:

100 mg/L nominal concentration

Measured Concentrations [mg/L]
Nominal Concentration Measured concentrations Measured concentrations
Test Item t = 0 h t = 72 h
Blank control < LOD < LOD
100 0.033 < LOD

Details on test conditions:

TEST SYSTEM
- Test vessel: flasks
- Type: open
- Material, size, headspace, fill volume: glass, total volume 65 mL, 20 mL, 45mL
- Aeration: no
- Initial cells density: 2340 cell number/mL
- Control end cells density: Blank control mean 581130 cells/mL; 100 mg/L test item mean 572917 cells/mL
- No. of vessels per concentration (replicates): 6
- No. of vessels per control (replicates): 6

GROWTH MEDIUM
- Standard medium used: yes

TEST MEDIUM / WATER PARAMETERS
- Preparation of dilution water: deionised water was sterilized by using an autoclave.
- Total organic carbon: < 1 ppm
- Metals: Ca, Mg, K, Fe, Na, Mn, Zn, Co, Cu, Mo
- Pesticides: < LOD
- Alkalinity: not stated
- Ca/Mg ratio: Ca 1,0213:1 Mg
- Conductivity: not stated

OTHER TEST CONDITIONS
- Sterile test conditions: yes
- Adjustment of pH: no
- Photoperiod: 96 h
- Light intensity and quality: 5000 lux

EFFECT PARAMETERS MEASURED (with observation intervals if applicable):
- Determination of cell concentrations: Before the start of incubation and every 24 hours, the cell number was determined with an electronic particle counter
- Chlorophyll measurement: no

Reference substance (positive control):

yes

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 2

Key result

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

cell number

Effect concentrations 3

Key result

Duration:

72 h

Dose descriptor:

LOEC

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 4

Key result

Duration:

72 h

Dose descriptor:

LOEC

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

cell number

Effect concentrations 5

Key result

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 6

Key result

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

cell number

Effect concentrations 7

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 8

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

cell number

Details on results:

- Exponential growth in the control (for algal test): yes
- Observation of abnormalities (for algal test): no
- Unusual cell shape: no
- Colour differences: no
- Flocculation: no
- Adherence to test vessels: no
- Aggregation of algal cells: no
- Any stimulation of growth found in any treatment: no
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: not stated
- Effect concentrations exceeding solubility of substance in test medium: yes

Results with reference substance (positive control):

Parameter Value 95% confidence interval
72h ErC50 0.79 mg/L 0.79 mg/L – 0.79 mg/L
72h EyC50 0.39 mg/L 0.35 mg/L – 0.45 mg/L

The 72h-EC50 values of potassium dichromate (K2Cr2O7, CAS No. 7778-50-9) were determined in a separate reference test.

For the estimation of the 72h-EC50 values of the positive control, the fits showed sufficient statistical correspondence of the data with the dose-response-equation. The values were within the range of the laboratory.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The study was performed as a limit test at 100 mg/L. Incubation time (test system Desmodesmus subspicatus) was 72 hours. The cell concentration of each replicate was determined by measuring the cell numbers every 24 hours with an electronic particle counter. Growth rate μ and the yield1 were determined from the cell number at the respective observation times.
No significant inhibition of algal growth was observed.