Reaction products of stearic acid, diethylenetriamine and N-aminoethylethanolamine and acetic acid

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:

January 23 - 25, 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Solubility trial and range-finding test were non-GLP

Analytical monitoring:

no

Remarks:

No confirmatory analysis of the test solutions was performed due to lack of an analytical method.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: A primary stock concentrate of Reaction products of stearic acid, diethylenetriamine and N-aminoethylethanolamine and acetic acid, with a nominal concentration of 100 mg/L, was prepared by weighing a nominal 0.2 g (actual weight: 0.19992 g) of test substance into a 2000 mL volumetric flask and made up to volume with culture medium. The stock was then sonicated for 60 minutes. This stock was used to prepare the test solutions by direct addition of the appropriate amount of concentrate to dilution water in a volumetric flask.
- Controls: The control consisted of culture medium only.
- Evidence of undissolved material: The resultant stock was observed to be a cloudy, colourless dispersion with fine particles visible and bubbles on surface.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna.
- Source: Continuous laboratory cultures at Scymaris Limited.
- Age of parental stock: 18 ± 1 days old and had been maintained with a twice weekly renewal of reconstituted water medium since birth.
- Feeding during test: No.
- Food type: Prior to the test, Daphnia magna were fed a mixed algae diet of Chlorella vulgaris, strain CCAP 211/12 and Pseudokirchneriella subcapitata, strain CCAP 278/4.
- Amount: Dependent on age and density.
- Frequency: Daily ration.

Test type:

static

Water media type:

other: Reconstituted water medium (Elendt's M4)

Limit test:

no

Total exposure duration:

48 h

Hardness:

248.7 as CaCO3 mg/L.

Test temperature:

Temperature values taken at 0, 24, and 48 hours were 20.6, 20.4, and 20.2 °C respectively (20 ± 1 °C).

pH:

7.80 to 7.99.

Dissolved oxygen:

8.66 to 9.16 mg/L.

Conductivity:

616 µS/cm.

Nominal and measured concentrations:

Non-GLP range-finding test: 0 (control), 0.01, 0.1, 1.0, 10, and 100 mg/L (nominal).
Definitive test: 0.95, 3.1, 9.8, 31, and 100 mg/L (nominal).

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass beakers.
- Type: Covered with loose fitting glass lids.
- Material, size, headspace, fill volume: 250 mL nominal capacity (containing 200 mL test solution).
- Aeration: No.
- Type of flow-through: Static.
- No. of organisms per vessel: Five.
- No. of vessels per concentration (replicates): Four replicates per test concentration.
- No. of vessels per control (replicates): Four.

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Reconstituted water medium (Elendt's M4).
- Total organic carbon: <0.7 mg/L.
- Pesticides: Highest organophosphorus pesticides: <0.01 µg/L; Highest organochlorine pesticides: <0.01 µg/L.
- Alkalinity: 39.2 (as CaCO3 mg/L).
- Conductivity: 616 µS/cm.
- Culture medium different from test medium: No.

OTHER TEST CONDITIONS
- Photoperiod: 16 hours of light and 8 hours dark with a 20-minute transition period provided.

EFFECT PARAMETERS MEASURED
Daphnia magna were considered to be affected if they exhibited no whole-body movement, relative to the water, within a period of 15 seconds even if movement of individual appendages was visible. Daphnia magna so affected were termed immobile.

RANGE-FINDING STUDY
- Test concentrations: 0 (control), 0.01, 0.1, 1.0, 10, and 100 mg/L (nominal).
- Results used to determine the conditions for the definitive study: A 100 mg/L test concentration was selected as the highest concentration and a spacing factor between test concentrations of 3.2 was selected based on the toxicity and solubility observed in the range-finding test.

Reference substance (positive control):

no

Key result

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

74 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

17 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

Based on immobility compared to the control (p <0.05), the 48-hour No Observed Effect Concentration (NOEC) was determined to be 9.8 mg/L and the Lowest Observed Effect Concentration (LOEC) was 31 mg/L. There was no immobility observed in the dilution water control. At 24 hours, it was noted in the nominal 31 and 100 mg/L test vessels that test substance had formed some larger particles. Some of these particles were observed to have fallen to the bottom of the test vessels and some were stuck to mobile daphnia. At 48 hours, the nominal 3.1 and 9.8 mg/L test concentrations were observed to be slow moving and at the bottom of test vessels when compared to the control. It was also noted that in the 9.8, 31 and 100 mg/L test concentrations large particles of test substance had formed and were visible physically interfering with the daphnia by sticking to them.

Validity criteria fulfilled:

yes

Conclusions:

A 48-hour acute toxicity experiment in the aquatic invertebrate Daphnia magna concluded a 24- and 48-hour EC50 of 74 and 17 mg/L, respectively, for Reaction products of stearic acid, diethylenetriamine and N-aminoethylethanolamine and acetic acid. The registered substance does not pose a short-term toxicity hazard to aquatic invertebrates, such as Daphnia magna, under the conditions of this study (CLP Regulation (EC) No. 1272/2008).

Executive summary:

To determine the acute (48-hour) toxicity of Reaction products of stearic acid, diethylenetriamine and N-aminoethylethanolamine and acetic acid to the aquatic invertebrate Daphnia magna, a static test was performed according to Good Laboratory Practise (GLP) and OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test). An initial non-GLP range-finding test was carried out at 0 (control), 0.01, 0.1, 1.0, 10, and 100 mg/L, the results of which were used to establish the concentration range of the definitive test; 0 (control), 0.95, 3.1, 9.8, 31, and 100 mg/L. Immobility with respect to whole-body movement was selected as an indicator of toxicity.

The validity criteria of the test were satisfied as no immobility or other signs of stress were observed in the control and dissolved oxygen concentration remained at ≥3 mg/L. Over the duration of the study, larger particles of the test substance were observed to have formed and some had adhered to the Daphnia magna, physically interfering with their movement. The 24- and 48-hour EC50 was determined to be 74 and 17 mg/L, respectively. The 48-hour NOEC was calculated to be 9.8 mg/L and the LOEC to be 31 mg/L. According to CLP Regulation (EC) No 1272/2008, Reaction products of stearic acid, diethylenetriamine and N-aminoethylethanolamine and acetic acid can be regarded as non-acutely toxic to aquatic invertebrates under the conditions of this study.

Description of key information

A 48-hour acute toxicity test in the aquatic invertebrate Daphnia magna was undertaken in accordance with OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test). A 24- and 48-hour EC50 of 74 and 17 mg/L, respectively, was determined for Reaction products of stearic acid, diethylenetriamine and N-aminoethylethanolamine and acetic acid. The registered substance can be regarded as being non-acutely toxic under the conditions of this study (CLP Regulation (EC) No. 1272/2008).

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

17 mg/L