Betaines, coco alkyldimethyl(3-sulfopropyl)

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2018-03-06 - 2018-03-08 (experimental phase)

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

OECD Guideline for Testing of Chemicals No. 202, adopted 13. Apr. 2004:
”Daphnia sp., Acute Immobilisation Test“

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Version / remarks:

Council Regulation (EC) No. 440/2008, Method C.2. “Daphnia sp. Acute Immobilisation Test”, adopted 30. May 2008

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Betaines, coco alkyldimethyl(3-sulfopropyl)

EC Number:

269-225-1

EC Name:

Betaines, coco alkyldimethyl(3-sulfopropyl)

Cas Number:

68201-55-8

Molecular formula:

C7H17NO3S·[CH2]6-16

IUPAC Name:

[3-(dodecyldimethylazaniumyl)propyl]trioxo-λ⁶-sulfanuide

Constituent 2

Reference substance name:

Water

EC Number:

231-791-2

EC Name:

Water

Cas Number:

7732-18-5

Molecular formula:

H2O

IUPAC Name:

Water

Test material form:

liquid

Remarks:

Aqueous solution: clear, colourless to yellowish liquid

Details on test material:

- Storage: Room Temperature (20 ± 5°C)

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: sponsor

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: The test item was stored in a closed vessel dark and dry at room temperature (15.8 - 23.0°C).

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 0.46 / 1.0 / 2.2 / 4.6 / 10 mg/L (test item)

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
A stock solution containing 10.1 mg/L test item in dilution water was prepared. The lower concentrations were prepared by dilution of this stock solution with dilution water.
- Evidence of undissolved material (e.g. precipitate, surface film, etc.): none stated

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Strain/clone: Daphnia magna STRAUS Berlin
Selection of the test system was made following the proposal of the guidelines.
- Source: Umweltbundesamt Berlin; In-house breeding since 27. September 2007
- Feeding during test: no
- Food type: unicellular green algae (Desmodesmus subspicatus)

Selection of Daphnia
19.25 hours before the start of the test, the adult animals were separated from the young. 1 hour before test start, the adults were caught with the help of a glass tube, and the new-born Daphnia, aged between 0 and 18.25 hours, were sieved from the medium and immediately placed into a beaker containing dilution water. After the settling-in period, animals which showed no apparent damage were used for the test.
Switching from M4-medium (husbandry) to Dilution water (test) has been shown not to cause any detrimental effects for test Daphnia.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Post exposure observation period:

none

Test conditions

Hardness:

Resulting hardness in mmol/L: 2.502
Resulting hardness in mg CaCO3/L: 250

Test temperature:

20 ± 2 °C

pH:

7.8

Dissolved oxygen:

8.3 - 8.7 mg/l

Nominal and measured concentrations:

0, 0.46 / 1.0 / 2.2 / 4.6 / 10 mg/L (nominal, test item)
The tested concentrations were based on the result of a non-GLP pre-test (Immobility after 48 h: 100 % at 10 and 100 mg/L, 0 % at 1 and 0.1 mg/L).

Details on test conditions:

TEST SYSTEM
- Test vessel: glass beakers, nominal volume 50 mL, tall shape
- Material, size, headspace, fill volume: containing 20 ± 5 mL test solution
- Aeration: After preparation, the dilution water was aerated.
- Renewal rate of test solution (frequency/flow rate): none
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
- No. of vessels per vehicle control (replicates): n/a

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16/8 hours
- Light intensity: neon tubes

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): immobility (after 24 and 48 hours), pH, dissolved oxygen (after 0 and 48h)

RANGE-FINDING STUDY
- Test concentrations: 0.1, 1, 10, 100 mg/l
- Results used to determine the conditions for the definitive study: The tested concentrations were based on the result of a non-GLP pre-test (Immobility after 48 h: 100 % at 10 and 100 mg/L, 0 % at 1 and 0.1 mg/L).

Reference substance (positive control):

yes

Remarks:

Potassium dichromate K2Cr2O7 (CAS No. 7778-50-9) was used as positive control in a current reference study.

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

24 h

Dose descriptor:

EC50

Remarks:

test item

Effect conc.:

9.44 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Remarks:

aqueous solution

Basis for effect:

mobility

Remarks on result:

other: 95%-confidence interval 7.69 - 12.55 mg/L

Effect concentrations 2

Duration:

24 h

Dose descriptor:

EC50

Remarks:

solid content

Effect conc.:

5.192 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

act. ingr.

Basis for effect:

mobility

Effect concentrations 3

Duration:

48 h

Dose descriptor:

EC50

Remarks:

test item

Effect conc.:

2.49 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Remarks:

aqueous solution

Basis for effect:

mobility

Effect concentrations 4

Key result

Duration:

48 h

Dose descriptor:

EC50

Remarks:

solid content

Effect conc.:

1.37 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

act. ingr.

Basis for effect:

mobility

Effect concentrations 5

Duration:

48 h

Dose descriptor:

NOEC

Remarks:

test item

Effect conc.:

1.33 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Remarks:

aqueous solution

Basis for effect:

mobility

Effect concentrations 6

Duration:

48 h

Dose descriptor:

NOEC

Remarks:

solid content

Effect conc.:

0.73 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

act. ingr.

Basis for effect:

mobility

Effect concentrations 7

Duration:

48 h

Dose descriptor:

LOEC

Remarks:

test item

Effect conc.:

2.82 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Remarks:

aqueous solution

Basis for effect:

mobility

Effect concentrations 8

Duration:

48 h

Dose descriptor:

LOEC

Remarks:

solid content

Effect conc.:

1.55 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

act. ingr.

Basis for effect:

mobility

Details on results:

- Behavioural abnormalities: none stated
- Mortality of control: none immobilized
- Other adverse effects control: none stated
- Abnormal responses: none stated
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: none stated
- Effect concentrations exceeding solubility of substance in test medium: none

Results with reference substance (positive control):

- Results with reference substance valid? yes
- Relevant effect levels: 24h-EC50i
- Limit test: no
- Dose-response test: yes
- ECx: 24h-EC50i = 1.6 mg/l
- Other: Potassium dichromate K2Cr2O7 (CAS No. 7778-50-9) was used as positive control in a current reference study. The 24h-EC50i value was determined as 1.6 mg/L. The value was within the requested range for the 24h-EC50 between 0.6 - 2.1 mg/L of potassium dichromate K2Cr2O7 as specified in the OECD guideline. Since the fits showed sufficient statistical correspondence of the data with the dose-response-equation, this reference study can be considered valid.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The study was conducted under GLP according to OECD guideline 202 and EU method C.2 on the registered substance itself. The method is to be considered scientifically reasonable with no deficiencies in documentation or deviations from the guidelines, the validity criteria were met. Hence, the results can be considered as reliable to assess the toxicity of the test item resp. Sulfobetaines, coco alkyldimethyl(3-sulfopropyl) towards daphnids.
The study was performed using 5 concentrations ranging from nominally 0.46 to 10 mg/L of the test item, i.e. an aqueous solution of Sulfobetaines, coco alkyldimethyl(3-sulfopropyl), allowing the re-calculation to the solid content, which is the actually registered substance. For each test concentration, 20 Daphnia were exposed to the test item for 48 hours in a static test system. After 24 and 48 hours, the immobilised Daphnia were counted.
The three highest concentrations showed toxicity between 85 and 100% immobilisation. None of the animals was immobilised in the blank control.
Potassium dichromate K2Cr2O7 (CAS No. 7778-50-9) was used as positive control in a current reference study to assure that the test conditions are reliable.
At the beginning and at the end of the test, the content of the test item in the test solutions was determined using HPLC-UV -determination. The measured concentrations at the beginning of the test were between 109 and 122% of the nominal concentrations and after 48 hours the measured concentrations were between 115 and 149% of the nominal concentrations.
Therefore, the determination of the biological results was based on the geometric mean of the measured concentration.
No observations were made which might cause doubts concerning the validity of the study outcome. All validity criteria were met.
The result of the test is considered valid.
The measured 48h EC50 of the aqueous solution was determined to be 2.49 mg/L, which corresponds to a 48h EC50 = 1.3695 mg/L of the registered substance, Sulfobetaines, coco alkyldimethyl(3-sulfopropyl). Based on the obtained results, Sulfobetaines, coco alkyldimethyl(3-sulfopropyl) does not need to be classified as acutely toxic to the environment (limit value for classification as acutely toxic: 1 mg/l), but as it is not biodegradable it should be classified as hazardous to the aquatic environment Cat. 2 (chronic) according to the Regulation (EC) No. 1272/2008.

Executive summary:

The study was conducted under GLP according to OECD guideline 202 and EU method C.2 on an aqueous solution of the registered substance Sulfobetaines, coco alkyldimethyl(3-sulfopropyl).

One valid experiment was performed.

The study was performed using 5 concentrations ranging from nominally 0.46 to 10 mg/L. For each test concentration, 20 Daphnia were exposed to the test item for 48 hours in a static test system. After 24 and 48 hours, the immobilised Daphnia were counted.

The three highest concentrations showed significant toxicity between 85 and 100% immobilisation. None of the animals was immobilised in the blank control.

Potassium dichromate K2Cr2O7 (CAS No. 7778-50-9) was used as positive control in a current reference study to assure that the test conditions are reliable.

At the beginning and at the end of the test, the content of the test item in the test solutions was determined using HPLC-UV-determination. The measured concentrations at the beginning of the test were between 109 and 122% of the nominal concentrations and after 48 hours the measured concentrations were between 115 and 149% of the nominal concentrations.

Therefore, the determination of the biological results was based on the geometric mean of the measured concentration.

The following results were determined for the test item Sulfobetaines, coco alkyldimethyl(3-sulfopropyl), aqueous solution (species: Daphnia magna).

48h NOEC = 1.33 mg/L

48h LOEC = 2.82 mg/L

24h EC50 = 9.44 mg/L

48h EC50 = 2.49 mg/L

Those values can be re-calculated to the content of the solid Sulfobetaines, coco alkyldimethyl(3-sulfopropyl), giving values of:

48h NOEC = 0.73 mg/L

48h LOEC = 1.55 mg/L

24h EC50 = 5.19 mg/L

48h EC50 = 1.37 mg/L