Fatty acids, coco, esters with 1,3-butanediol

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

Study period:

02 - 04 Nov 2018

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:

Apr 2004

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: OECD monograph No. 23

GLP compliance:

yes (incl. QA statement)

Remarks:

Secrétariat général du GIPC, Ivry-sur-Seine, Cedex, France (15 Nov 2018)

Analytical monitoring:

yes

Remarks:

GC-MS/MS

Details on sampling:

- Concentrations: Control, 0.88, 1.94, 4.27, 9.39, 20.66, 45.45 and 100 mg/L (after 0 and 48 h)
- Sample storage conditions before analysis: Samples were immediately analysed.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: The test item was poorly soluble under the test conditions. Therefore, the test solutions were prepared as Water Accommodated Fractions (WAF) according to OECD guideline 23. The WAFs were prepared individually. The respective test item amounts were directly added to the test medium and mixed for 72 h to achieve an equilibrated concentration of dissolved and dispersed or emulsified components in the aqueous phase.
- Differential loading: Yes
- Controls: Test medium only, without test item.
- Evidence of undissolved material: Since the test solutions were not filtered, the test solutions were therefore emulsions of the test element.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Water flea
- Strain/clone: Clone 5
- Source: bred at test laboratory
- Age at test start: Between 6 and 24 h old, produced from parthenogenically reproducing brood female population
- Breeding conditions: Juveniles were selected daily by filtration. The juveniles from at least the 2nd litter were used for the test. Culture medium: Elendt M4; Temperature: 20 ± 2 °C; Lighting: 16 h light/8 h dark; pH: 6 - 9; CaCO3 concentration: 140 - 250 mg/L; Feeding: Daily; Food type: Pseudokirchneriella subcapitata and Chlorella vulgaris suspensions

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

140 - 250 mg/L CaCO3 (Elendt M4 medium)

Test temperature:

20 ± 2 °C

pH:

7.4 - 8.0

Dissolved oxygen:

7.4 - 8.8 mg/L

Nominal and measured concentrations:

Control, 0.88, 1.94, 4.27, 9.39, 20.66, 45.45 and 100.30 mg/L (nominal loading rates of WAF, for analytical results see field any other information on results incl. tables)

Details on test conditions:

TEST SYSTEM
- Test vessel: 100 mL glass flasks filled with 50 mL test solution
- 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: The test medium used was OECD medium, prepared according to OECD guideline 202. It was reconstituted with chemical reagents and deionised water.

OTHER TEST CONDITIONS
- Adjustment of pH: Between 6 and 9
- Photoperiod: 16 h light/ 8 h dark
- Light intensity: 231-235 lux

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : mobility after 24 and 48 h

RANGE-FINDING STUDY
- Test concentrations: nominal loading rates: 1, 10, 100, mg/L (WAF)
- Results used to determine the conditions for the definitive study: 100% immobiliatiosation at a loading rate of 100 mg/L (WAF)

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Duration:

48 h

Dose descriptor:

EL50

Effect conc.:

37.59 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% confidence interval: 34.59 - 40.98 mg/L

Details on results:

- Behavioural abnormalities: None
- Other biological observations: None
- Mortality of control: 0%
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: The test item was poorly soluble and test solutions were prepared as Water Accommodated Fractions (WAFs). However, chemical analysis detected very low amounts of test item in the WAFs.
- Effect concentrations exceeding solubility of substance in test medium: Yes

Results with reference substance (positive control):

EC50 (24 h): 1.851 mg/L (95% confidence limits: 1.753 – 1.948 mg/L, starting date19 September 2018)

Reported statistics and error estimates:

The probits method was used to estimate the EC50 after 24 and 48 h.

BIOLOGICAL RESULTS

Table 1: Immobilized Daphnids after 24 and 48 h.

Loading rate [mg/L]	Immobilized Daphnids
	24 h	48 h
0	0	0
0.88	0	0
1.94	0	0
4.27	0	0
9.39	0	0
20.66	0	1
45.45	9	14
100	16	20

VALIDITY CRITERIA

The study fulfilled the validity criteria defined by the guideline and is thus considered valid and reliable (Table 1).

Table 2: 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.	Actual value: 0%	Yes
The dissolved oxygen concentration at the end of the test should be ≥ 3 mg/L in control and test vessels.	Actual value: 7.8 mg/L	Yes

 

ANALYTICAL RESULTS

Analytical findings are summarized in Table 2.

Table 2. Analytical results.

		Nominal loading rate [mg/L]
Time	Analyte	0	0.88	1.94	4.27	9.39	20.66	45.45	100
0 h	[mg monoester/L]	< LOQ	< LOQ	< LOQ	< LOQ	< LOQ	< LOQ	< LOQ	< LOQ
	[mg diester/L]	< LOQ	< LOQ	< LOQ	< LOQ	< LOQ	< LOQ	1.13	2.08
	[mg diester2/L]	< LOQ	< LOQ	< LOQ	< LOQ	< LOQ	< LOQ	0.90	1.32
	[mg diester3/L]	< LOQ	< LOQ	< LOQ	< LOQ	< LOQ	< LOQ	< LOQ	0.95
	[mg diester4/L]	< LOQ	< LOQ	< LOQ	< LOQ	< LOQ	< LOQ	< LOQ	0.82
48 h	[mg monoester/L]	< LOQ	< LOQ	< LOQ	< LOQ	< LOQ	< LOQ	< LOQ	< LOQ
	[mg diester/L]	< LOQ	< LOQ	< LOQ	< LOQ	< LOQ	< LOQ	1.23	2.64
	[mg diester2/L]	< LOQ	< LOQ	< LOQ	< LOQ	< LOQ	< LOQ	0.75	1.68
	[mg diester3/L]	< LOQ	< LOQ	< LOQ	< LOQ	< LOQ	< LOQ	< LOQ	1.04
	[mg diester4/L]	< LOQ	< LOQ	< LOQ	< LOQ	< LOQ	< LOQ	< LOQ	0.99

Limit of Quantification (LOQ) = 3.02 mg/L for monoester

LOQ = 0.52 mg/L for diester1

LOQ = 0.73 mg/L for diester2

LOQ = 0.79 mg/L for diester3

LOQ = 0.74 mg/L for diester4

 

BIOLOGICAL RESULTS

Based on the number of immobilized daphnids, the derived EC50 after 24 h was 51.56 mg/L (95% confidence limits: 42.88 – 60.25 mg/L) and the derived EC50 after 48 h was 37.59 mg/L (95% confidence limits: 34.59 – 40.98 mg/L).

Validity criteria fulfilled:

yes

Remarks:

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

Description of key information

EL50 (48 h) = 37.59 mg/L (nominal loading rate, OECD 202)

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

37.59 mg/L

Additional information

One study is available testing the toxicity of the substance towards aquatic invertebrates. The study was conducted according to the OECD guideline 202 and GLP standards. Daphnia magna was used as the test organism and was exposed in a static testing regime to nominal loading rates of 0.88, 1.94, 4.27, 9.39, 20.66, 45.45 and 100 mg/L for 48 h. Since the substance fulfils the UVCB criteria and is partly poorly water soluble the test solutions were prepared as water-accommodated fractions (WAF). The test item quantification was performed by GC-MS/MS at 0 and 48 h. The analytical recovery of the constituents was mostly below the quantification limit. The test resulted in an EL50 (48 h) of 37.59 mg/L (nominal loading rates). All validity criteria were met and the study is considered valid.