1,4-Cyclohexanedicarboxylic acid, 1,4-bis[2-(2-ethoxyethoxy)ethyl] ester

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:

29 March 2011 - 05 May 2011

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: This study has been performed according to OECD and/or EC guidelines and according to GLP principles

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2011

Report date:

2011

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

yes

Remarks:

: Inadvertently, 20 daphnids per conc were exposed to the control and the highest test concentration during the range-finding test. Evaluation: The test was suitable for gaining information about the range of concentrations to be used in the final test.

Test guideline 2

Qualifier:

equivalent or similar to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Version / remarks:

(2008)

Test guideline 3

Qualifier:

equivalent or similar to guideline

Guideline:

other: ISO 6341 (Water quality - Determination of the Inhibition of the Mobility of Daphnia magna Straus (Cladocera, Crustacea)) (1996)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Neosolue-Aqulio

IUPAC Name:

Neosolue-Aqulio

Constituent 2

Reference substance name:

1,4-bis[2-(2-ethoxyethoxy)ethyl] cyclohexane-1,4-dicarboxylate

EC Number:

618-829-7

Cas Number:

922165-31-9

Molecular formula:

C20H36O8

IUPAC Name:

1,4-bis[2-(2-ethoxyethoxy)ethyl] cyclohexane-1,4-dicarboxylate

Details on test material:

- Name of test material (as cited in study report): Neosolue-Aqulio
- Description/Physical state: Clear colourless to very pale yellow liquid
- Molecular formula: C20H36O8
- Molecular weight: 404.5
- Analytical purity: 99.5% (GC)
- Lot/batch No.: TVI-714
- Expiration date of the lot/batch: 07 October 2012 (Retest date)
- Storage condition of test material: At room temperature in the dark

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 100 mg/l and control (0 mg/l) at t=0 and t=48 h
- Sampling method: 2 ml from the approximate centre of the test vessels
- Sample storage conditions before analysis: Samples were stored in a freezer until analysis

At the end of the exposure period, the replicates were pooled at each concentration before sampling.

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- method: Test substance was stirred in medium at a nominal concentration of 100 mg/l applying 15 minutes of magnetic stirring to accelerate the dissolution. The lower test concentrations for the range-finding test were prepared by subsequent dilutions of the 100 mg/l concentration in test medium. The final test solutions were all clear and colourless.
- Evidence of undissolved material (e.g. precipitate, surface film, etc): no

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna (Crustacea, Cladocera) (Straus, 1820)
- Source: In-house laboratory culture with a known history.
- Age at study initiation: < 24 hours
- Method of breeding: With newborn daphnids, i.e. less than 3 days old, by placing about 250 of them into 10 litres of medium in an all-glass culture vessel.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Test conditions

Hardness:

180 mg/l expressed as CaCO3

Test temperature:

Between 19.6 and 20.3°

pH:

Between 7.9 and 8.0

Dissolved oxygen:

Between 9.0 and 9.2 mg/l

Nominal and measured concentrations:

Nominal: loading rate 0 and 100 mg/l
Measured: 100 mg/l (start) and 99 mg/l (end) in the pooled solutions prepared at 100 mg/l.

Analysis of the samples taken during the limit test showed that measured concentrations were in agreement with nominal at the start (100%) and remained stable during the 48-hour exposure period (99% of nominal at the end). Given these results, effect parameters were based on nominal concentrations.

Details on test conditions:

TEST SYSTEM
- Test vessel: 100 ml, all-glass, containing 80 ml of test solution
- Type (delete if not applicable): open
- Aeration: no
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
- Introduction of daphnids: Within 15 minutes after preparation of the test solutions
- other: no feeding

TEST MEDIUM / WATER PARAMETERS
- Test medium: Adjusted ISO medium
- Source/preparation of dilution water: tap water purified by Reverse Osmosis (RO-water, GEON Waterbehandeling, Berkel-Enschot, The Netherlands)
- the following chemicals (analytical grade) are dissolved in the purified tap water:
CaCl2.2H2O 211.5 mg/l
MgSO4.7H2O 88.8 mg/l
NaHCO3 46.7 mg/l
KCl 4.2 mg/l
- Culture medium different from test medium: yes (M7 medium is used for breeding)

OTHER TEST CONDITIONS
- Adjustment of pH: not reported
- Photoperiod: 16 hours daily
- Light intensity: not reported

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- mobility
- mortality

TEST CONCENTRATIONS
Range finding study:
- Test concentrations: 0, 0.1, 1, 10, 100 mg/l
- Results used to determine the conditions for the definitive study: EC50
Final test:
- Test concentrations: 0, 100 mg/l

Reference substance (positive control):

yes

Remarks:

potassium dichromate (K2Cr2O7)

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 2

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 3

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

No immobility was observed at both the control and the limit concentration during the test period.

Analysis of the samples taken during the limit test showed that measured concentrations were in agreement with nominal at the start (100%) and remained stable during the 48-hour exposure period (99% of nominal at the end). Given these results, effect parameters were based on nominal concentrations.

Results with reference substance (positive control):

- Results with reference substance valid? yes

The 24h-EC50 was 0.68 mg/l with a 95% confidence interval between 0.61 and 0.78 mg/l.

The 48h-EC50 was 0.55 mg/l with a 95% confidence interval between 0.50 and 0.63 mg/l.

Reported statistics and error estimates:

No EC50 could be calculated because the test substance proved to be non-toxic (EC50 > maximum concentration tested).

Any other information on results incl. tables

In a range-finding test, no (significant) immobility was observed at any of the test concentrations (0.1, 1, 10, 100 mg/L; nominal concentration was 100 mg/L, lower concentrations are dilutions thereof) and the control during the test period (48 h). Based on the range-finding test results, the expected EC₅₀was above a nominal concentration of 100 mg/l.

The results of measurement of pH and oxygen concentrations (mg/l) remained within the limits prescribed by the protocol (pH: 6.0-8.5, not varying by more than 1.5 unit; oxygen: >=3 mg/l at the end of the test).

The temperature continuously measured in a temperature control vessel varied between 19.6 and 20.3°C during the test, and complied with the requirements as laid down in the protocol (18-22°C, constant within 2°C).

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Under the conditions of the described test, Neosolue-Aqulio did not induce acute immobilisation of Daphnia magna at 100 mg/l after 48 hours of exposure (NOEC). Hence, the 48h-EC50 was >100 mg/l.