12-hydroxy-N-(2-hydroxyethyl)octadecan-1-amide

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:

December 22, 2017 - April 12, 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Data is from experimental study report

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

The samples were taken from the biological phase of the study. Collecting, storage and handing over of the samples were the Study Director’s responsibility. Duplicate samples from the freshly prepared test media of all test concentrations and the controls were taken at the start of the test and at day 1.
For the determination of the stability of the test item under the test conditions and of the maintenance of the test item concentrations during the test period, duplicate samples from the aged test media of all test concentrations and the control were collected at day 1 (after 24 hours of exposure) and at the end of the test by pouring together the contents of the test beakers of each treatment.
All samples (apart from stock solution samples in organic solvent if prepared) were diluted by a factor of 2 with acetonitrile.
Additional samples of the control and the dilution solvent were taken at test start and test end without any sample treatment.
The concentrations of the test item 12-Hydroxy-N-(2-hydroxyethyl)octadecan-1-amide were analysed in the duplicate test media samples from all test concentrations, in the duplicate control samples and in the additional control and solvent samples, from both sampling times.

Vehicle:

no

Details on test solutions:

Test Concentrations:
An aqueous solution of 12-Hydroxy-N-(2-hydroxyethyl)octadecan-1-amide in test media with a concentration (nominal: 100.1 mg/L) as close to saturation as possible (referred to as a ´stock solution´) was obtained first. This stock solution and dilutions of this “stock solution” by 1:2, 1:4, 1:8 and 1:16 were prepared for testing. Additionally, a control was tested in parallel.The stock solutions and dilutions correspond to the following nominal concentrations of the test item: 100.1, 50.1, 25.0, 12.5 and 6.26 mg test item/L, and a control.

Dosage of Test Item:
Before test start and at test medium renewal, a ´stock solution´ (100.1 mg/L) of 12-Hydroxy-N-(2-hydroxyethyl)octadecan-1-amide in test medium was prepared as close to the water solubility limit as possible by dissolving 120.12 and 120.12 mg test item in 1200.0 and 1200.0 mL test water . The test medium was stirred with an excess of 12-Hydroxy-N-(2-hydroxyethyl)octadecan-1-amide in a vessel for 24 hours at 500 rpm in the dark. Afterwards the test medium was allowed to settle for 1 hour. This ´stock solution´ was withdrawn from a tap at the centre of the vessel, after first flushing the tap and tubing with a small aliquot, and then mixed with test medium to produce the desired set of test concentrations (see ´Test Concentrations´ above).
The test media was prepared just before introduction of the daphnia (=start of the test) and test medium renewal on Day 1.

Test organisms (species):

Daphnia magna

Details on test organisms:

Species:Daphnia magna (Straus), clone 5
Age at Test Start:From 1.83 to 18.75 hours old
Sex:Female

Origin:The daphnids introduced in the test were taken from ibacon's in house laboratory culture.
Breeding Conditions:The daphnids were bred in the laboratories of ibacon under similar temperature and light conditions as used in the test. The cultivation of the parental daphnids was performed in Elendt M4 medium (see 6.5). The test organisms were not first brood progeny. The daphnids in the stock culture were fed at least on all working days with green algae (Desmodesmus subspicatus) freshly grown in the laboratories of ibacon.

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

Water Hardness: 2.5 mmol/L (= 250 mg/L) as CaCO3

Test temperature:

19.9 to 20.1 °C in the freshly prepared media;
19.4 to 19.8°C in the aged test media

pH:

7.9 to 8.0 in the freshly prepared media;
7.8 to 7.9 in the aged test media

Dissolved oxygen:

8.8 to 9.0 mg/L in the freshly prepared media;
8.7 to 8.9 mg/L in the aged test media

Nominal and measured concentrations:

Summary of Analytical Results

Sample description Geometric mean measured1,2
Nominal % of concentration3
concentration nominal3 [µg test item/L]

Control n.a. n.a.
1:16 dilution 0.0265 1.65
1:8 dilution 0.0336 4.21
1:4 dilution 0.0179 4.48
1:2 dilution 0.0121 6.04
'stock solution' 100.1 mg/L 0.0240 24.0

1 Mean value of all measured samples per treatment group
2 Calculated according to OECD Guidance Document No. 23, Annex 2
3 The tabulated results represent results rounded to three significant digits
n.a.: not applicable

Details on test conditions:

Introduction of Daphnids: 20 daphnids per control and test concentration, divided into 4 groups of 5 animals, each group in 60 mL test medium
Replicates:The test was performed with four replicates per treatment group.
Exposure Time:48 hours

Test Procedure:A semi-static test system with a test medium renewal on Day 1 was chosen to keep the concentrations of test item as constant as possible in the test media.

Immobility:The mobility of the daphnids was determined by visual observation after 24 and 48 hours. Those animals that are not able to swim within 15 seconds after gentle agitation of the test beaker were considered to be immobile.

Reference substance (positive control):

yes

Remarks:

For the evaluation of the quality of the Daphnia clone and the consistency of the experimental conditions, the reference item potassium dichromate is tested at least twice a year to demonstrate satisfactory test conditions.

Key result

Duration:

48 h

Dose descriptor:

EL50

Effect conc.:

> 100.1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EL10

Effect conc.:

> 100.1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

NOELR

Effect conc.:

> 100.1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

LOELR

Effect conc.:

> 100.1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Validity criteria fulfilled:

yes

Remarks:

The Control Immobilisation Rate was 0 % and no daphnids showed signs of disease or stress. The Dissolved Oxygen Concentration was >= 8.8 mg O2/L in the control and test vessels at the end of the test. Thus the validity criteria were met.

Conclusions:

The toxic effect of the test item 12-Hydroxy-N-(2-hydroxyethyl)octadecan-1-amide to Daphnia magna was assessed in a semi-static concentration-response test. The 48-hour NOEC (NOELR) was determined to be ≥ 100.1 mg test item/L. The 48-hour LOEC (LOELR) was determined to be > 100.1 mg test item/L and the 48-hour EC50 (EL50) value was determined to be > 100.1 mg test item/L. The initial concentrations and the maintenance of the exposure concentrations during the test were verified in the analytical part. All reported results refer to nominal values since the concentrations applied reflect the solubility limit of the test substance.

Executive summary:

The toxic effect of the test item 12-Hydroxy-N-(2-hydroxyethyl)octadecan-1-amide to Daphnia magna was assessed in a semi-static concentration-response test. The 48-hour NOEC (NOELR) was determined to be ≥ 100.1 mg test item/L. The 48-hour LOEC (LOELR) was determined to be > 100.1 mg test item/L and the 48-hour EC50 (EL50) value was determined to be > 100.1 mg test item/L.The initial concentrations and the maintenance of the exposure concentrations during the test were verified in the analytical part. All reported results refer to nominal values since the concentrations applied reflect the solubility limit of the test substance.

Description of key information

Short term toxicity to aquatic invertebrate:

The toxic effect of the test item 12-Hydroxy-N-(2-hydroxyethyl)octadecan-1-amide to Daphnia magna was assessed in a semi-static concentration-response test. The 48-hour NOEC (NOELR) was determined to be ≥ 100.1 mg test item/L. The 48-hour LOEC (LOELR) was determined to be > 100.1 mg test item/L and the 48-hour EC50 (EL50) value was determined to be > 100.1 mg test item/L.The initial concentrations and the maintenance of the exposure concentrations during the test were verified in the analytical part. All reported results refer to nominal values since the concentrations applied reflect the solubility limit of the test substance. Based on the above effect concentration it can be concluded that test substance is not classified as per CLP criteria.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100.1 mg/L

Additional information

Short term toxicity to aquatic invertebrate:

The toxic effect of the test item 12-Hydroxy-N-(2-hydroxyethyl)octadecan-1-amide to Daphnia magna was assessed in a semi-static concentration-response test. The 48-hour NOEC (NOELR) was determined to be ≥ 100.1 mg test item/L. The 48-hour LOEC (LOELR) was determined to be > 100.1 mg test item/L and the 48-hour EC50 (EL50) value was determined to be > 100.1 mg test item/L.The initial concentrations and the maintenance of the exposure concentrations during the test were verified in the analytical part. All reported results refer to nominal values since the concentrations applied reflect the solubility limit of the test substance. Based on the above effect concentration it can be concluded that test substance is not classified as per CLP criteria.