Dodecyltrimethylammonium bromide

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:

2018-04-25 to 2018-05-04

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)

Version / remarks:

2004-04-13

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Version / remarks:

2008-05-30

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Sampling method: The samples were taken from the biological phase of the study. One sample from the freshly prepared stock solution and duplicate samples from the freshly prepared test media of all test concentrations and the control were taken at the start of the test. 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 test media of all test concentrations and the control were collected at the end of the test (after 48 hours) by pouring together the contents of the test beakers of each treatment.
All samples were diluted by a factor of two with acetonitrile. Additional samples of the control and the dilution solvent were taken at each sampling without any sample treatment.
- Sample storage conditions before analysis: All samples were stored in a freezer (< - 20 °C), protected from light, until analysis was performed. Afterwards the samples were again stored deep frozen (< -20 °C) and will be kept stored up to the date of the final report.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: A stock solution of 10 mg test item/L was prepared by dissolving 10.9 mg test item into 1090 mL test water by intense stirring for 10 minutes. Adequate volumes of this stock solution were diluted with test water to prepare the test media of the desired test concentrations. The test media were prepared just before introduction of the daphnids (= start of the test).
- Controls: In the blank control, test water was used without addition of the test item.
- Evidence of undissolved material: No

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Water flea
- Strain/clone: Clone 5
- Source: The daphnids introduced in the test were taken from in-house laboratory culture
- Age of parental stock: From 6.5 to 22.5 hours old
- Feeding during test: No

BREEDING CONDITIONS
The daphnids were bred in the laboratory under similar temperature and light conditions as used in the test. The cultivation of the parental daphnids was performed in Elendt M4 medium. 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.


ACCLIMATION: Not necessary (cultivation conditions similar to test conditions)

Test type:

static

Water media type:

freshwater

Total exposure duration:

48 h

Post exposure observation period:

No

Hardness:

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

Test temperature:

19.9 to 20.3 °C at test start;
19.8 to 20.0 °C at test end

pH:

7.9 to 8.0 at test start;
7.8 to 7.9 at test end

Dissolved oxygen:

8.9 to 9.0 mg/L at test start;
8.7 to 8.8 mg/L at test end

Salinity:

Not applicable

Conductivity:

Not measured

Nominal and measured concentrations:

Nominal: 0.500, 0.227, 0.103, 0.047 and 0.021 mg test item/L
Mean value of all measured samples per treatment group: 97 - 109% of nominal

Details on test conditions:

TEST SYSTEM
- Test vessel: Beakers
- Material, size, fill volume: Glass, 100 mL (nominal), 60 mL (fill volume), covered with lid
- Aeration: No
- No. of organisms per vessel: 5
- No. of vessels per concentration: 4
- No. of vessels per control: 4

TEST MEDIUM
- Preparation of dilution water: Reconstituted test water (Elendt "M4" Medium) was prepared using deionised water

OTHER TEST CONDITIONS
- Adjustment of pH: No
- Photoperiod: 16 h light : 8 h dark
- Light intensity: 220 to 520 lux


VEHICLE CONTROL PERFORMED: No

RANGE-FINDING STUDY: Performed
- Results used to determine the conditions for the definitive study: Yes

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

0.135 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% confidence limits: 0.113 - 0.163 mg/L

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

0.276 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

other: EC20

Effect conc.:

0.103 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% confidence limits: 0.078 - 0.122 mg/L

Duration:

24 h

Dose descriptor:

other: EC20

Effect conc.:

0.199 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC10

Effect conc.:

0.09 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% confidence limits: 0.063 - 0.108 mg/L

Duration:

24 h

Dose descriptor:

EC10

Effect conc.:

0.163 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

0.047 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

24 h

Dose descriptor:

NOEC

Effect conc.:

0.047 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

LOEC

Effect conc.:

0.103 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

24 h

Dose descriptor:

LOEC

Effect conc.:

0.103 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Behavioural abnormalities: No
- Observations on body length and weight: No
- Other biological observations: No
- Mortality of control: No
- Other adverse effects control: No
- Abnormal responses: No
- Any observations that might cause a difference between measured and nominal values: No
- Effect concentrations exceeding solubility of substance in test medium: No

Results with reference substance (positive control):

In the most recent test with the reference item potassium dichromate performed in January 2018 the EC50 after 24 hours was determined to be 1.06 mg test item/L, indicating that the sensitivity of the daphnids was consistent with the level proposed by the OECD 202 guideline (EC50-24 h between 0.6 and 2.1 mg potassium dichromate/L).

Reported statistics and error estimates:

The 24-hour and 48-hour EC50, EC20 and EC10 and the 95 % confidence limits were calculated by probit analysis. The NOEC and LOEC after 24 and 48 hours were determined directly from the raw data.

Validity criteria fulfilled:

yes

Conclusions:

In a static Acute Immobilisation Test with Daphnia magna according to OECD TG 202 and EU Method C.2 the 48-hour EC50 of the test item was determined to be 0.135 mg/L.

Executive summary:

An Acute Immobilisation Test according to OECD TG 202, EU Method C.2 and GLP-principles was carried out in order to determine the influence of the test item on the mobility of Daphnia magna. For this purpose, young daphnids (< 24 hours old) were exposed in a static test to nominal test item concentrations of 0.500, 0.227, 0.103, 0.047 and 0.021 mg/L for 48 hours (4 replicates per treatment, 5 animals per replicate). In parallel a blank control was performed (4 replicates, each containing 5 animals). The suitability of the test system was confirmed by a separate test with the reference item potassium dichromate (24 -hour EC50 = 1.06 mg/L). In result, the 48-hour NOEC was determined to be 0.047mg test item/L. The 48-hour LOEC was determined to be 0.103 mg test item/L and the 48-hour EC50 value was calculated to be 0.135 mg test item/L. The initial concentrations and the maintenance of the exposure concentrations during the test were verified by LC-MS analysis. All reported results refer to nominal values since the concentrations of the test item were within ± 20% of the nominal concentrations during the test. All validity criteria of the guidelines were fulfilled.

Description of key information

In a static Acute Immobilisation Test with Daphnia magna according to OECD TG 202 and EU Method C.2 the 48-hour EC50 of the substance was determined to be 0.135 mg/L (reference 6.1.3 -1).

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

0.135 mg/L

Additional information

An Acute Immobilisation Test according to OECD TG 202, EU Method C.2 and GLP-principles was carried out in order to determine the influence of the test item on the mobility of Daphnia magna. For this purpose, young daphnids (< 24 hours old) were exposed in a static test to nominal test item concentrations of 0.500, 0.227, 0.103, 0.047 and 0.021 mg/L for 48 hours (4 replicates per treatment, 5 animals per replicate). In parallel a blank control was performed (4 replicates, each containing 5 animals). The suitability of the test system was confirmed by a separate test with the reference item potassium dichromate (24 -hour EC50 =1.06 mg/L). In result, the 48-hour NOEC was determined to be 0.047mg test item/L. The 48-hour LOEC was determined to be 0.103 mg test item/L and the 48-hour EC50 value was calculated to be 0.135mg test item/L.The initial concentrations and the maintenance of the exposure concentrations during the test were verified by LC-MS analysis. All reported results refer to nominal values since the concentrations of the test item were within ± 20% of the nominal concentrations during the test. All validity criteria of the guidelines were fulfilled (reference 6.1.3 -1).