1-{[1-({1-[(2,2-dimethylpropanoyl)oxy]propan-2-yl}oxy)propan-2-yl]oxy}propan-2-yl 2,2-dimethylpropanoate

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:

14 Dec 2018 - 09 Jan 2019

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2019

Report date:

2019

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

2004

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: OECD Guideline 23 (Guidance document on aquatic toxicity testing of difficult substances and mixtures)

Version / remarks:

2000

GLP compliance:

yes

Remarks:

Statement on compliance with GLP included (22 Jan 2019)

Test material

Test material information

Constituent 1

Reference substance name:

1-{[1-({1-[(2,2-dimethylpropanoyl)oxy]propan-2-yl}oxy)propan-2-yl]oxy}propan-2-yl 2,2-dimethylpropanoate

Molecular formula:

C19H36O6

IUPAC Name:

1-{[1-({1-[(2,2-dimethylpropanoyl)oxy]propan-2-yl}oxy)propan-2-yl]oxy}propan-2-yl 2,2-dimethylpropanoate

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: All concentrations were sampled.
- Sampling: Samples were taken at the beginning and at the end of the experiment.

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Due to the low solubility of the substance in water an extraction was performed to extract the soluble components ot the test item according to the OECD guidance 23. 100, 58.82 and 34.6 mg/L solutions were prepared in culture medium. The solutions were extracted for 72 h at 10 rpm and room temperature. From the extracts of 34.6 mg/L the solutions of 20.35, 11.97 mg/L were prepared under stirring.
- Controls: Only medium

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Source: Breeder in Eurofins Biolab Test Facility
- Age: 6 - 24 h
- Feeding during test: no

MAINTENANCE
- Glass Beaker: 500 mL
- Medium: Reconstituted water
- Conditions: 20 °C, 16h light/8 h darkness, 140-250 mL CaCO3/L
- Type of food: green algae Pseudokirchneriella subcapitata and yeast Saccharomyces cerevisiae.
- Water change: 3 times/week

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test conditions

Hardness:

140 - 250 mg CaCI3/L

Test temperature:

20.1 - 20.2 °C

pH:

7.66 - 8

Dissolved oxygen:

5.94 - 6.42 mg/L

Salinity:

-

Conductivity:

-

Nominal and measured concentrations:

Nominal: 0 (control), 11.97, 20.35, 34.60, 58.82, 100 mg/L
Measured initial: 0 (control), 9.76, 15.99, 28.08, 39.14, 46.30 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass Beaker (500 mL)
- Aeration: no
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: reconstituted water according to guideline
- Culture medium different from test medium: No
- Intervals of water quality measurement: pH and dissolved oxygen have been measured at the beginning and at the end of the test in the highest concentration in the treated group and control. Temperature of the assay environment has been measured at the beginning and at the end of the test.

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: no light

EFFECT PARAMETERS MEASURED:
Immobilization was evaluated after 24 and 48 h.

RANGE-FINDING STUDY
- Test concentrations: 0.01 - 100 mg/L.
- Results used to determine the conditions for the definitive study: Yes but no further details given in the report.

Reference substance (positive control):

not specified

Results and discussion

Effect concentrations

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

18.98 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: Test item concentration stable during test

Details on results:

- Mortality of control: no mortality
- Other biological observations: At tested concentrations of nominal 100 mg/L and 58.82 mg/L some Daphnia were trapped on the upper layer of the solution of each replica.

Reported statistics and error estimates:

EC50 was evaluated using EPA Probit Analysis Program Version 1.5.

Any other information on results incl. tables

ANALYTICAL RESULTS

Table 1: nominal and measured concentrations of the samples.

Nominal concentration [mg/L]	Measured concentration t=0 in mg/L	% initial recovery	Measured concentration t= 48 h in mg/	% stability
100	46.30	46.3	52.5	113.33
58.82	39.14	66.6	46.9	119.75
34.60	28.08	81.2	29.1	103.53
20.35	15.99	79	17.2	107.72
11.97	9.76	81.6	11.1	114.17

The test item was stable during the test therefore the statistical calculation of the EC50 was performed with measured concentrations of T = 0.

BIOLOGICAL RESULTS

Table 2: Immobilized daphnids.

Control	24 h	48 h
1	0/5	0/5
2	0/5	0/5
3	0/5	0/5
4	0/5	0/5
100 mg/L
1	5/5	5/5
2	4/5	5/5
3	5/5	5/5
4	5/5	5/5
58.82 mg/L
1	4/5	5/5
2	4/5	5/5
3	5/5	5/5
4	4/5	5/5
34.6 mg/L
1	2/5	3/5
2	2/5	3/5
3	2/5	4/5
4	1/5	3/5
20.35 mg/L
1	0/5	1/5
2	0/5	1/5
3	1/5	2/5
4	0/5	2/5
11.97 mg/L
1	0/5	1/5
2	0/5	0/5
3	1/5	1/5
4	0/5	1/5

VALIDITY CRITERIA

Table 3: Validity criteria for OECD 202.

Criterion from the guideline	Outcome	Validity criterion fulfilled
In the control, including the control containing the solubilising agent, not more than 10% of the daphnids should have been immobilized.	0%	yes
The dissolved oxygen concentration at the end of the test should be ≥ 3 mg/L in control and test vessels.	5.94 - 6.42 mg/L	yes

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

For further details please refer to “Any other information on results incl. tables”.