Reaction mass of ethyl 2-ethyl-6,6-dimethylcyclohex-2-enecarboxylate and ethyl 2,3,6,6-tetramethylcyclohex-2-enecarboxylate

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

4 July to 29 september 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2016

Report date:

2016

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Ethyl 2-ethyl-6,6-dimethylcyclohex-2-ene-1-carboxylate

EC Number:

261-020-5

EC Name:

Ethyl 2-ethyl-6,6-dimethylcyclohex-2-ene-1-carboxylate

Cas Number:

57934-97-1

Molecular formula:

C13H22O2

IUPAC Name:

ethyl 2-ethyl-6,6-dimethylcyclohex-2-ene-1-carboxylate

Constituent 2

Reference substance name:

Ethyl 2,3,6,6-tetramethylcyclohex-2-ene-1-carboxylate

EC Number:

278-776-7

EC Name:

Ethyl 2,3,6,6-tetramethylcyclohex-2-ene-1-carboxylate

Cas Number:

77851-07-1

Molecular formula:

C13H22O2

IUPAC Name:

ethyl 2,3,6,6-tetramethylcyclohex-2-ene-1-carboxylate

Specific details on test material used for the study:

Test material name (as stated in report): Givescone
Batch No. VE00409039
Appearance: Colourless to pale yellow liquid
Expiration date: January 21, 2018

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

Sample preparation and Extraction: Liquid -liquid partitioning with toluene

Test solutions

Vehicle:

no

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

Species: The test system used in this study was Daphnia magna STRAUS (clone M10), a water flea, cultured at ECT Oekotoxikologie GmbH since December 22, 2011.
Origin: The organisms were originally supplied by KU Leuven, Belgium.

Study design

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test conditions

Hardness:

254 [mg/L CaCO3]

Test temperature:

19.6 - 20.5°C

pH:

7.8

Dissolved oxygen:

8.0 - 8.8 [mg/L]

Conductivity:

672 [μS/cm]

Nominal and measured concentrations:

Nominal 6.25, 12.5, 25.0, 50.0 and 100% of a saturated solution at a loading rate of 100 mg/L
Measured 1.05, 2.09, 4.00, 7.73, 17.48 time-weighted mean measured concentration over 48 h [mg test item/L]

Details on test conditions:

Material and methods:
Test system: Daphnia magna (Straus)
Age of exposed daphnids at start < 24 hours
Medium: Elendt Medium M4
Endpoint: ECx (e.g. EC50, EC20, EC10), NOEC/LOEC
Biological parameters: Immobilisation
Test duration: 48 h
Target temperature: 18 - 22°C
Volume of test solution per test vessel: 50-60 mL
Number of daphnids per test vessel: 5
Photoperiod: 16 h light / 8 h dark
Aeration: none
Feeding during exposure: none
Test units: 60-mL glass beakers
Test concentrations (nominal): Control;
6.25, 12.5, 25.0, 50.0 and 100% of a saturated
solution at a loading rate of 100 mg/L
Number of replicates per concentration: 4
Number of replicates in the controls: 4
Renewal of test solution during exposure: Semi-static, renewal after 24 hours of exposure
Chemical analysis of test concentrations: At start, after 24 h, and at end of exposure
Data evaluation: Evaluation of immobility. Weibull analysis, Fisher
exact test.

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Results and discussion

Effect concentrations

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

11.09 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The EC50 (48 hours) has been determined to be 11.09 mg/L in this test conditions.

Executive summary:

An OECD 202 acute Daphnia magna immobilisation test was conducted for the substance Givescone according to the OECD Guideline 202 under semi static conditions. The EC50 (48 hours) has been determined to be 11.09 mg/L under these test conditions.