2-[[3-(dimethylamino)propyl]methylamino]ethanol

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:

29 OCT 2013 - 14 JAN 2014 (experimental phase)

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Version / remarks:

of Commission Regulation (EC) No 440/2008

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

as of April 2004

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 0 mg/L (control) and 100 mg/L
- Sampling method: Water samples were taken from one replicate of the control and all replicates of the 100 mg/L treatment, samples from treatment replicates were pooled, at the start (0 h) and end of the test (48 h)
- Sample storage conditions before analysis: samples were stored frozen and thawed with the aid of sonication prior to analysis

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: 200 mg was dissolved in test water and the volume adjusted to 2 L to give the 100 mg/L test concentration. The test concentration was inverted several times to ensure adequate mixing and homogeneity.
- Controls: one blank control
- Test concentration separation factor: none, only one concentration
- Evidence of undissolved material (e.g. precipitate, surface film, etc.): no, solutions were clear and colourless

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Strain/clone: not stated
- Age at study initiation (mean and range, SD): less than 24 hours old
- Stage and instar at study initiation: 1st instar
- Method of breeding: Adult Daphnia were maintained in 150 mL glass beakers containing Elendt M7 medium in a temperature-controlled room at approximately 20 °C. The lighting cycle was controlled to give a 16 hours light and 8 hours darkness cycle with 20 minute dawn and dusk transition periods. Each culture was fed daily with a mixture of algal suspension (Desmodesmus subspicatus) and Tetramin® flake food suspension. Culture conditions ensured that reproduction was by parthenogenesis.
- Source: inhouse lab culture
- Feeding during test: no

ACCLIMATION
- No acclimation described

Test type:

static

Water media type:

freshwater

Remarks:

Reconstituted water (ISO medium)

Limit test:

yes

Total exposure duration:

48 h

Hardness:

250 mg/L as CaCO3

Test temperature:

approx. 20°C (room temperature)

pH:

Test start: 7.3 (control) and 7.9 (100 mg/L)
Test end: 7.6 (control) and 8.1 (100 mg/L)

Dissolved oxygen:

9.0 mg O2/L throughout the test

Nominal and measured concentrations:

100 mg/L (nominal)
99.3 mg/L (measured, 0 h)
97.7 mg/L (measured, 48 h)

Details on test conditions:

TEST SYSTEM
- Test vessel: glass jars
- Type (delete if not applicable): open
- Material, size, headspace, fill volume: glass jars, 250 mL, filled with 200 mL test solution
- Volume of solution: 200 mL
- Aeration: none
- No. of organisms per vessel: 5 daphnids
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: preparation before the test start, composition details under 'Any other information', Table 1
- Culture medium different from test medium: yes

OTHER TEST CONDITIONS
- Adjustment of pH: yes, pH of test solutions was adjusted to pH 7.9 prior to addition of daphnids
- Photoperiod: 16:8 light:dark
- Light intensity: 630 to 685 lux

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): immobilisation, every 24 hours

VEHICLE CONTROL PERFORMED: no

RANGE-FINDING STUDY
- Test concentrations: 0.1, 1.0, 10 and 100 mg/L
- Results used to determine the conditions for the definitive study: yes, no immobilisation was observed up to 100 mg/L in the second trial (in the first trial complete immobilisation at 100 mg/L was observed, but the first trial was invalid as the pH value of the 100 mg/L test solution was outside the range of pH 6-9)

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Immobilisation of control: After 24 hours, one out of the 5 daphnids in one replicate of the control was observed to be trapped at the surface, however, as this observation was no longer present after 48 hours, this was not considered to have an effect on the outcome of the test.

Results with reference substance (positive control):

- Results with reference substance valid? yes
- Relevant effect levels: 0.32, 0.56, 1.0, 1.8 and 3.2 mg/L
- Limit test: no
- Dose-response test: yes
- ECx (95% CI): 24h-EC50 = 1.0 mg/L (0.91-1.2 mg/L), 48h-EC50 = 0.71 mg/L (0.65-0.76 mg/L)

Reported statistics and error estimates:

No statistical evaluation; EC50 values were estimated by inspection of the immobilisation data.

Validity criteria fulfilled:

yes

Remarks:

Control mortality below 10% (0%) and oxygen concentration at test end higher than 3 mg/L (9 mg/L)

Conclusions:

The study was performed under GLP according to the guidelines OECD 202 (2004) and EU-Method C.2, without deviations which may have impact on the validity of the study. Thus, the results were obtained via a scientifically reasonable method. Hence, there is no doubt that the obtained results are not reliable. According to the reported 48h-EC50 value of >100 mg/L the test substance possesses no toxic potential towards aquatic invertebrates.

Executive summary:

In the present study the acute toxicity of the test item towards aquatic invertebrates was investigated according to relevant OECD test guideline 202 and EU-Method C.2, without deviations which may have impact on the validity of the study. The study was performed under GLP conditions and a GLP certificate is included in the final report.

Daphnia magna was used as test organisms. 20 animals per treatment were exposed to the test substance at a concentration of 100 mg/L for 48 hours in a static test. A blank control was included and the reference substance potassium dichromate was tested at regular intervals. Under the conditions used for the test, the following effect concentrations were determined based on immobilisation:

48h-EC₅₀ > 100 mg/L

As a conclusion of the analytical part of this study, a slight change in the concentration of the test substance in the test solutions at test start and test end was observed, but the recoveries were still well above 90%. Therefore, the biological results were based on the nominal concentrations of the test substance.

Description of key information

acute toxicity of substance 2-[[3-(dimethylamino)propyl]methylamino]ethanol to freshwater invertebrates Daphnia magna (OECD 202):

48h-EC₅₀: >100 mg/L  (nominal, based on mobility)

48h-NOEC: 100 mg/L  (nominal, based on mobility)

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

EC50

Effect concentration:

100 mg/L