Fatty acids C16-18 (even numbered), mono and di esters with Sucrose

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

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

No chemical analysis of test concentrations.

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

1984

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: A pre-test was performed to examine the solubility of the test substance in the test medium. A solution was prepared at 100 mg/L. The test substance did not completely dissolve, even after half an hour of stirring. Instead, layer of foam appeared at the surface of the solution and undissolved test substance particles remained present. Treatment with ultra sonic waves increased the dissolving of the test substance substantially, but after overnight standing, the test substance had precipitated. Therefore, preparation of test solutions during the test included a stabilisation period of ca. 24 hours after preparation to obtain the maximum soluble concentration and at the same time to prevent testing with flocculated test substance. Preparation started with ultrasonic treatment and magnetic stirring as performed in the pre-test. The stabilised test solutions contained flocculated test substance and were filtered through a paper filter (Schleicher and Schuell 604) to remove the flocks of undissolved test substance (> ca. 5 µm). The resulting solutions (clear and colourless) were defined as the Water Accommodated Fractions (WAFs).
- Eluate: no
- Differential loading: yes
- Controls: yes, test medium control

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Source: in-house culture
- Age of parental stock (mean and range, SD): Maximum age of cultures was 4 weeks
- Feeding during test: none
- Breeding conditions: Each batch was started with newborn animals, i.e. less than three days old, by placing about 250 of them into 10 L of medium in an all-glass culture vessel. The temperature was 18-22 °C and daphnids were fed daily with a suspension of fresh water algae. The test medium was the same as for the exposure (M7 medium).

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Hardness:

250 mg/L as CaCO3

Test temperature:

20.3 - 20.5 °C

pH:

8.0 - 8.1

Dissolved oxygen:

8.9 - 9.1 mg O2/L

Nominal and measured concentrations:

Nominal: control, 100 mg/L

Details on test conditions:

TEST SYSTEM
Test vessel
- Material, size, headspace, fill volume: glass, 100 mL, headspace: 20 mL, fill volume: 80 mL
- Aeration: no
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: according to guideline
- Culture medium different from test medium: same as test
- Intervals of water quality measurement: regularly

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

EFFECT PARAMETERS MEASURED
- Mobility was recorded after 24 and 48 h

RANGE-FINDING STUDY
- Test concentrations: dilution range of 1-100% of a WAF prepared at 10 mg/L and to 100% WAF prepared at 100 mg/L.
- Results used to determine the conditions for the definitive study: A maximum of 10% immobilisation was recorded at the different dilutions tested.

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Duration:

48 h

Dose descriptor:

EL50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

WAF

Basis for effect:

mobility

Details on results:

- Mortality of control: 0%
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: Test solutions were clear and colorless after filtration.

Results with reference substance (positive control):

- Results with reference substance valid? yes
- Limit test: no
- Dose-response test: yes (control, 0.1, 0.18, 0.32, 056, 1.0, 1.8 mg/L)
- ECx: EC50 (48 h): 0.50 mg/L (95% CI: 0.45 - 0.61 mg/L)

Description of key information

EL50 (48 h) > 100 mg/L (nominal, OECD 202)

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L

Additional information

One experimental study is available investigating the short-term toxicity of Fatty acids C16-18 (even numbered), mono and diesters with sucrose (no CAS) to aquatic invertebrates. The study was performed according to OECD 202 (GLP) with the water flea Daphnia magna.
A pre-test was performed to examine the solubility of the test substance in the test medium. A solution was prepared at 100 mg/L. The test substance did not completely dissolve, even after half an hour of stirring. Instead, layer of foam appeared at the surface of the solution and undissolved test substance particles remained present. Therefore, preparation of test solutions during the test included a stabilisation period of ca. 24 h after preparation to obtain the maximum soluble concentration and at the same time to prevent testing with flocculated test substance. Preparation started with ultrasonic treatment and magnetic stirring as performed in the pre-test. The stabilised test solutions contained flocculated test substance and were filtered through a paper filter (Schleicher and Schuell 604) to remove the flocks of undissolved test substance (> ca. 5 µm).
A Water Accommodated Fraction of nominal 100 mg/L was prepared and used for testing. No chemical analysis was performed. However, the chemical analysis in the acute fish study indicated that the substance is stable in aqueous solutions. During the course of the test no immobilization of D. magna was recorded and an EL50 (48 h) of > 100 mg/L was derived.