Dodecanoic acid, monoester with oxybis[propanediol]

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:

30 Jan - 01 Feb 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

April 13, 2004

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Dodecanoic acid, monoester with oxybis[propanediol]

EC Number:

619-220-9

Cas Number:

96499-68-2

Molecular formula:

not applicable, the substance is UVCB

IUPAC Name:

Dodecanoic acid, monoester with oxybis[propanediol]

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: all concentration levels and control
- Sampling method: Approx. 60 mL of test solution was sampled from the middle layer of each test vessel. Sampling was performed at the start of exposure, before and after the renewal at 24 h and at the end of exposure.

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: The test sample and dilution water were mixed to produce a nominal concentration of 80.0 mg/L and stirred for 48 hours. The suspension was filtered with a membrane filter (0.22 µm pore size) to prepare the stock solution. The test solutions were prepared by diluting the stock solution with dilution water.
- Eluate: no
- Differential loading: no
- Controls: blank control, reference control
- Evidence of undissolved material (e.g. precipitate, surface film, etc.): After filtration, the stock solution was clear.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Source: The University of Sheffield, United Kingdom; supplied on July 9, 1990
- Age of parental stock: 20 d
- Feeding during test: no
- Breeding conditions of parental stock: breeding in dechlorinated tap water at 20 ± 1 °C; photoperiod: 16 h light/8 h darkness; survival of parental stock: 100%; during breeding, the daphnids were fed Chlorella vulgaris once a day (corresponding to 0.1-0.2 mg organic carbon per day)
- Age of daphnids for test: less than 24 h

ACCLIMATION
- Acclimation period: not specified

Study design

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test conditions

Hardness:

43 mg/L (Ca, Mg)

Test temperature:

20.0 - 20.1 °C

pH:

Control: 7.7 - 7.9
Treatment: 7.8 - 8.0

Dissolved oxygen:

Control: 7.9 - 9.0 mg/L
Treatment: 7.6 - 9.0 mg/L

Conductivity:

17 mS/m

Nominal and measured concentrations:

nominal: Control, 0.316, 1.00, 3.16, 10.0, 31.6 and 100 mg/L
measured (geometric mean): < detection limit, 0.215, 0.681, 2.27, 7.48, 23.7 and 77.4 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 100 mL glass beaker, covered with transparent plastic lid
- Renewal rate of test solution: fresh test solutions were prepared after 24 h
- 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: dechlorinated tap water
- Total organic carbon: < 0.5 mg/L
- Particulate matter: < 1 mg/L
- Chlorine: < 0.02 mg/L
- Alkalinity: 42 mg/L
- Ca/mg ratio: 3.14
- Conductivity: 17 mS/m
- Culture medium different from test medium: same as test medium
- Intervals of water quality measurement: pH value, temperature and dissolved oxygen concentration were measured at test start, before and after the renewal at 24 h and at test end

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 h light/8 h dark

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : immobility and behavioural effects were observed after 24 and 48 h

RANGE-FINDING STUDY
Two preliminary tests were performed.
Test 1:
- Concentrations: 1.00, 5.00, 10.0 mg/L (nominal)
- Results used to determine the conditions for the definitive study: After 48 h, 0% immobility was observed at the two lowest concentration levels, while 90% immobilisation was observed at the highest concentration level.

Test 2:
- Concentrations: 1.00, 10.0, 100 mg/L (nominal)
- Results used to determine the conditions for the definitive study: After 48 h, 0% immobility was observed at the lowest concentration levels, while 70% immobilisation was observed at the intermediate concentration level and 100% immobilisation at the highest concentration level.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Results and discussion

Effect concentrations

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

9.69 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% CI could not be determined

Details on results:

- Behavioural abnormalities: After 48 h, one daphnid in the highest test concentration showed reduced activity.
- Mortality of control: 0%
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: No, the test solutions were clear and colourless at test start and end.

Results with reference substance (positive control):

- Results with reference substance valid? Yes
- EC50 (48 h) = 0.12 mg/L

Reported statistics and error estimates:

The 48 hour EC50 was calculated by Binomial test. For 24 hours, the EC50 was estimated as ">the highest test concentration" since immobility over 50% was not observed. In 0.316% exposure level, the test item concentrations were less than the determination limit throughout exposure duration. Therefore the test item concentration was represented as reference values which were calculated from a geometric series with a factor √10 and the measured concentration of the quantifiable lowest exposure level (1.00% exposure level).

Any other information on results incl. tables

Table 1: Immobility

Measured concentration [mg/L]	Vessel	24 hours		48 hours
		No. of immobilied daphnids/Total daphnids	Immobility [%]	No. of immobilied daphnids/Total daphnids	Immobility
Control	A	0/5	0	0/5	0
	B	0/5		0/5
	C	0/5		0/5
	D	0/5		0/5
0.215	A	0/5	0	0/5	0
	B	0/5		0/5
	C	0/5		0/5
	D	0/5		0/5
0.681	A	0/5	0	0/5	0
	B	0/5		0/5
	C	0/5		0/5
	D	0/5		0/5
2.27	A	0/5	0	0/5	0
	B	0/5		0/5
	C	0/5		0/5
	D	0/5		0/5
7.48	A	0/5	0	2/5	30
	B	0/5		1/5
	C	0/5		2/5
	D	0/5		1/5
23.7	A	5/5	55	5/5	100
	B	3/5		5/5
	C	2/5		5/5
	D	1/5		5/5
77.4	A	1/5	25	5/5	75
	B	2/5		4/5
	C	2/5		3/5
	D	0/5		3/5

 

Table 2: Validity criteria

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.	≥7.6 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”.