3,4-dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-2H-1-benzopyran-6-yl nicotinate

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:

22/05/1995 - 28/09/1995

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study according to international guideline (OECD Guideline 201) performed under GLP conditions, validity citeria met.

Data source

Reference

Reference Type:

other: published parts of study report

Title:

Unnamed

Year:

1995

Report date:

1995

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

3,4-dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-2H-benzopyran-6-yl acetate

EC Number:

231-710-0

EC Name:

3,4-dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-2H-benzopyran-6-yl acetate

Cas Number:

7695-91-2

Molecular formula:

C31H52O3

IUPAC Name:

2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-3,4-dihydro-2H-1-benzopyran-6-yl acetate

Test material form:

liquid: viscous

Specific details on test material used for the study:

- Name of test material (as cited in study report): d,l-a-Tocopheryl Acetate
- Substance type: vitamin derivative
- Physical state: liquid
- Storage condition of test material: at room temperature, in the dark

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: nominal concentrations are 5.8, 10, 18, 32, 58 and 100 mg/l
- Sampling method: Composite samples (about 150 ml per concentration and control) of each test concentration were drawn by mixing identical volumes of the test solutions taken from the test vessels. Samples of the test solution were taken immediately before and after 72 hours exposure and stock solution samples were taken 4 hours before exposure.
- Sample storage conditions before analysis: samples were stored at -18 to -22°C util analysis

Test solutions

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: 200.2 mg test substance were mixed with 2 ml; water containing 4 mg Tween 80. This blend were mixed and made up to 2000 ml with reconstituted water by polytron. Calculated amounts of stock solution to produce the desired test concentrations and vehicle to achieve identical vehicle concentration at all test concentrations were given into the water and were homogeneously distributed. The test solutions were equilibrated for 4 hours under test conditions. the algae were then transferred into the flasks.
- Controls: Yes, reconstituted water
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): Polyoxyethylen-sorbitan-mono-oleate (Tween 80)
- Concentration of vehicle in test medium (stock solution and final test solution(s) including control(s)): 2 mg/L
- Evidence of undissolved material (e.g. precipitate, surface film, etc): not relevant

Test organisms

Test organisms (species):

Raphidocelis subcapitata (previous names: Pseudokirchneriella subcapitata, Selenastrum capricornutum)

Details on test organisms:

TEST ORGANISM
- Common name: Selenastrum capricornutum
- Strain: Selenastrum capricornutum 61.81 SAG
- Source (laboratory, culture collection): Collection of algae cultures, Pflanzenphysiologisches Institut University, Göttingen, Germany
- Method of cultivation: according to OECD Guideline 201

ACCLIMATION
- Acclimation period: 3 days
- Culturing media and conditions (same as test or not): same as test
- Any deformed or abnormal cells observed: No

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test conditions

Hardness:

24 mg CaO/l

Test temperature:

21 - 25 +/- 1 °C

pH:

8.2 - 9.6 with no increase greater than 1.4 during the test.

Nominal and measured concentrations:

Nominal: 5.8, 10, 18, 32, 58 and 100 mg/l
Measured (start): 4.0, 7.0, 11.5, 19.0, 24.0 and 39.8 mg/l
Measured (end): 4.0, 6.5, 9.8, 14.1, 7.6 and 15.7 mg/l
Effect concentrations (based on actual mean concentrations): 4.0, 6.8, 10.7, 16.6, 15.8 and 27.8 mg/l

Details on test conditions:

TEST SYSTEM
- Test vessel: Erlenmeyer flask
- Type (delete if not applicable): closed (cotton stopper)
- Material, size, headspace, fill volume: glass, 100 ml volume (125 ml volume total) with 50 ml medium per flask
- Aeration: No
- Type of flow-through (e.g. peristaltic or proportional diluter): Not applicable, static test
- Renewal rate of test solution (frequency/flow rate): Not applicable, static test
- Initial cells density: 10.400 cells/ml
- Control end cells density: 1.246.000 cells/ml
- No. of organisms per vessel: Not applicable
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 6
- No. of vessels per vehicle control (replicates): 6

GROWTH MEDIUM
- Standard medium used: yes
- Detailed composition if non-standard medium was used: Not applicable

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Reconstituted water, composition according to guideline
- Conductivity: 160 uS
- Culture medium different from test medium: No
- Intervals of water quality measurement: 72h


OTHER TEST CONDITIONS
- Sterile test conditions: yes
- Adjustment of pH: No
- Photoperiod: continuously
- Light intensity and quality: cold white fluorescent light, 120 uE/m^2 sec +/- 20% (approximately 8000 lux)


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: [counting chamber; electronic particle counter; fluorimeter; spectrophotometer; colorimeter]: TOA counter

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 1.8

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 27.8 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 2

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 3

Key result

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

27.8 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 4

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 5

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 27.8 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

biomass

Effect concentrations 6

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Effect concentrations 7

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

27.8 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

biomass

Effect concentrations 8

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

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
- Other: No
- Effect concentrations exceeding solubility of substance in test medium

Reported statistics and error estimates:

A modified dunnet Multiple Comparison Test was used for calculation of the NOEC.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

exponential growth (>16 x) in controls, variability within limits

Conclusions:

The 72h EC50 (growth rate of Selenastrum capricornutum) of d,l-a-Tocopheryl Acetate was found to be >27.8 mg/l, the 72h NOEC (growth rate) was found to be 27.8 mg/l.

Executive summary:

The toxicity of d,l-a-Tocopheryl acetate towards the algae Selenastrum capricornutum was determined according to OECD Guideline 201 under GLP conditions. The 72h EC50 (growth rate) of d,1-a-Tocopheryl Acetate was found to be >27.8 mg/l, the 72h NOEC (growth rate) was found to be 27.8 mg/l.