L-Threonine, N-coco acyl derivs., monosodium salts

Biodegradation in water: screening tests

Administrative data

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

11.12.2017 - 08.01.2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EU Method C.4-D (Determination of the "Ready" Biodegradability - Manometric Respirometry Test)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Auf dem Aberg 1, D-57392 Schmallenberg, Germany

Test material

Test material information

Constituent 1

Reference substance name:

L-Threonine, N-coco acyl derivs., monosodium salts

Cas Number:

90583-79-2

Molecular formula:

n/a

IUPAC Name:

L-Threonine, N-coco acyl derivs., monosodium salts

Test material form:

solid

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: Ajinomoto Co., Inc., 15-1 Kyobashi 1-Chome, Chuo-Ku, Tokyo 104-8315 Japan/Batch No.: 160329
- Expiration date of the lot/batch: 29.03.2019

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: dark and cool place, protected from light

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: no

FORM AS APPLIED IN THE TEST (if different from that of starting material): solid

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

sewage, predominantly domestic, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge: withdrawn from the sewage treatment plant Ruhrverband Kläranlage, Schmallenberg, Germany. The sewage treatment plant was mainly fed with municipal wastewater
- Method of cultivation: samples were not washed with mineral medium after the arrival at the laboratory but kept aerobic until use
- Initial cell/biomass concentration: 29.6 mg dry mass/L

Duration of test (contact time):

28 d

Initial test substance concentration

Initial test substance concentration 1

Initial conc.:

100 mg/L

Based on:

test mat.

Initial test substance concentration 2

Initial conc.:

226 mg/L

Based on:

ThOD/L

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

TEST CONDITIONS
- Composition of medium: according to guideline
- Additional substrate: no
- Solubilising agent (type and concentration if used): no
- Test temperature: 22 °C ± 1°C
- pH: test start: 7.4± 0.2, test end: 7.2-7.8 (in all test vessels)
- pH adjusted: yes
- Aeration of dilution water: not reported
- Continuous darkness: yes

TEST SYSTEM
- Culturing apparatus: respirometer
- Number of culture flasks/concentration: 2
- Method used to create aerobic conditions: aeration during the test
- Measuring equipment: Sapromat

SAMPLING
- Sampling frequency: oxygen demand measured continuously via Sapromat respirometer

CONTROL AND BLANK SYSTEM
- Inoculum blank: yes
- Abiotic sterile control: yes (sterilized with HgCl2)
- Toxicity control: yes
- Other: Procedural control using sodium benzoate was performed

Reference substance

Reference substance:

benzoic acid, sodium salt

Remarks:

100 mg/L

Results and discussion

% Degradation

% Degradation 1

Key result

Parameter:

% degradation (O2 consumption)

Value:

74.2

St. dev.:

1

Sampling time:

14 d

Remarks on result:

other: mean of 2 determinations

% Degradation 2

Key result

Parameter:

% degradation (O2 consumption)

Value:

81.7

St. dev.:

0.3

Sampling time:

28 d

Remarks on result:

other: mean of 2 determinations

BOD5 / COD results

Results with reference substance:

The reference item sodium benzoate was degraded to 86 % within the first 14 days thus fulfilling the guideline requirements.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

According to the guideline, the test item TH-CS-11-T can be considered as being readily biodegradable.

Executive summary:

The ready biodegradation of the test material was investigated in a study conducted according to OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test) and EU Method C.4-D (Determination of the "Ready" Biodegradability - Manometric Respirometry Test) over a period of 28 days and using non-adapted activated sludge as inoculum. The biodegradation rate was determined by measurement of oxygen consumption. Inoculum blank, procedural/functional control with reference substance sodium benzoate and toxicity control using 100 mg/L test item and 100 mg/L reference compound were performed.

 

This study is regarded as reliable without restriction and satisfies the guideline requirements for ready biodegradation.

The test item proved to be readily biodegradable (82% biodegradation after 28d incubation) and fulfilling the 10-d-window criterion (71% biodegradation within 10 d-window). In the toxicity control containing both test and reference item, 80% biodegradation was measured within 14 d thus indicating that the test item was non-toxic to the inoculum at the concentration tested.