Phenethyl cinnamate

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

1984

Deviations:

yes

Remarks:

No analytical verification possible with DOC as concentrations were below the detection limit of the DOC apparatus.

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Version / remarks:

1992

GLP compliance:

yes

Analytical monitoring:

no

Remarks:

All samples had concentrations below the detection limit of the DOC apparatus.

Vehicle:

no

Details on test solutions:

- Stock solution: 100 mg/L test item
- Test dilutions: 1:16, 1:8, 1:4, 1:2, 1:1 dilutions of stock solution
- Test concentrations: 0.063 - 0.13 - 0.25 - 0.5 - 1 mg/L (assumed concentrations based on water solubility of 1 mg/L)
- Control: Dilution water without test item tested under the same conditions as the test groups.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Strain: Daphnia magna Straus (clone 5)
- Culture medium: Elendt M4, according to Elendt (1990), modified to a total hardness of 160 to 180 mg CaCO3/L.
- Feeding: 5 x weekly ad libitum with a mix of Scenedesmus subspicatus and Chlorella vulgaris, with an algae cell density of > 10e6cells/mL.
- Age: lees than 24h old
- Acclimatization: 2h in dilution water
- Number of study organisms per concentration and control: 20 animals, divided into 4 (2*) parallel samples, each with 5 (10*) animals
- Number of animals per test vessel: 5 (10*)
- Number of parallel samples per concentration: 4 (2*)
- Test temperature: 21+/-1°C
- Illumination: Diffuse light, illumination range 1.5 - 5 µmol.me-2.se-1
- Photoperiod: 16/8 h light/dark cycle

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

257 mg/L

Test temperature:

21 +/- 1°C

pH:

mean: 7.42

Dissolved oxygen:

> 5.21 mg/L (60% of the air saturation value at the temperature used)

Nominal and measured concentrations:

EC10, EC50 and EC100 values were not determinable within the tested concentration range.

Details on test conditions:

TEST SYSTEM
- Test vessels: Glass beakers (5 cm ID x 8 cm H), 50 mL
- Volume of the study medium: 20 mL
- Material, size, headspace, fill volume:
- Aeration:
- Type of flow-through (e.g. peristaltic or proportional diluter):
- Renewal rate of test solution (frequency/flow rate):
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

EFFECT PARAMETERS MEASURED
Mobility of the daphnids

RANGE-FINDING STUDY
- Test concentrations: 1:1, 1:10 and 1:100 dilution of stock solution: 100 mg/L (nominal)
- Results used to determine the conditions for the definitive study: immobilisation was only observed in the 1:1 dilution (20% on average). Therefore, the main test was conducted with 5 dilutions of the saturated solution ranging from 1:1 to 1:16 (dilution factor 2).

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 1 mg/L

Nominal / measured:

estimated

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: concentrations were estimated based on assumed water solubility limit of the substance

Key result

Duration:

48 h

Dose descriptor:

EC10

Effect conc.:

> 1 mg/L

Nominal / measured:

estimated

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: concentrations were estimated based on assumed water solubility limit of the substance

Details on results:

No biologically significant effect (< 10 %) was determined in the tested concentration levels. The EC10, EC50 and EC100 values were not determinable in the tested concentration range.

Results with reference substance (positive control):

EC- values after 24 h [mg/L]:
EC10: 1.2 mg/L; EC50 : 1.9 mg/L (CI 1.7 — 2.1); EC100: 5.8 mg/L.
The EC50- value of reference item is within the prescribed concentration range of 1.0 - 2.5 mg/L of validity criteria.

Results of the non-GLP range finding test:

Test dilution	% immobilization
	24h	48h
1:1	0	20
1:10	0	0
1:100	0	0

Results main test:

No immobilization observed in any of the treatments

Validity criteria fulfilled:

yes

Conclusions:

No biologically significant effect was determined in the tested concentration range up to 1 mg/L (calculated concentration based on water solubility, equal to 100 mg/L nominal), and so the EC10 and EC50 values were not determinable within the tested concentration range. It can hence be assumed that EC50 and EC10 > 1 mg/L (calculated concentration based on water solubility, equal to 100 mg/L nominal).

Executive summary:

In the current study the immobilisation of Daphnia caused by the test item was determined according to OECD 202 and EEC Method C.2.

The study was conducted under static conditions over a duration of 48 hours. Twenty test organisms were exposed to each test concentration and control. The test item was clearly dissolved in all tested concentration levels throughout exposure, however, the real test item concentrations could not be calculated based on the DOC-analysis because the water solubility of test item is below the detection limit of the DOC-analyser. Therefore, the concentrations of the test item were calculated based on the water solubility of the test item: 0.063 - 0.13 - 0.25 - 0.5 - 1 mg/L.

The reference substance showed an EC50 of 1.9 mg/L after 24 h, which is within the concentration range of 1.0 to 2.5 mg/L, fulfilling the criteria. Also the water quality parameters of pH-value and dissolved oxygen concentration measured at 0 and 48 h were within the acceptable limits.

No biologically significant effect was determined in the tested concentration range up to 1mg/L (based on water solubility, 100 mg/L nominal), and so the EC10 and EC50 values were not determinable within the tested concentration range.

Description of key information

For this endpoint, there is one study available in which the toxicity to Daphnia was assessed according to OECD 202. Under the conditions of the present study no biologically significant effects were observed in the tested concentration range up to 1 mg/L (assumed saturated solution based on water solubility; nominal concentration 100 mg/L), hence, it can be concluded that no biological significant effect has been determined within water solubility limits.

Additional information

The key study was performed according to the OECD Guideline 202.

The study was conducted under static conditions over a duration of 48 hours. Twenty test organisms were exposed to each test concentration and control. The test item concentration could not be calculated based on DOC-analysis because the water solubility of the test item (1 mg/L) is less than the determination limit of the DOC-analyser. Therefore the concentrations of the test item were set based on the water solubility of the test item and are 0.063; 0.13; 0.25; 0.5 and 1 mg/L. No biologically significant effect was determined in the tested concentration range up to 1 mg/L.

The EC10 and EC50 values were not determinable within the tested concentration range.