Sodium hydrogen N-(1-oxotetradecyl)-L-glutamate

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From December 30, 2015 to February 22, 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 310 (Ready Biodegradability - CO2 in Sealed Vessels (Headspace Test)

Version / remarks:

2006

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: EN ISO 10634:1995 - Guidance for the preparation and treatment of poorly soluble organic compounds for the subsequent evaluation of their biodegradability in an aqueous medium

Version / remarks:

1995

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Quality Assesment Statement is on page 4 of the attached report

Specific details on test material used for the study:

Batch no.: 3837 supplied by the sponsor
Purity: 25.5% in water (water solution)
Solubility: soluble in water
Storage condition of test material: room temperature (15 °C - 25 °C)
Stability and homogeneity of the test material in the vehicle/solvent under test conditions (e.g. in the exposure medium) and during storage: stable for 12 months minimum
Solubility: soluble and stable in water
Reactivity of the test material with the incubation material used (e.g. plastic ware): not reactive
pH (20 °C) = 6.22
Composition in C, H and N: C=12.88%, H= 9.80%, n= 0.97%, nominal concentration 20.78 mg/l TOC.
More information can be found on the attached report

Oxygen conditions:

aerobic

Inoculum or test system:

sewage, predominantly domestic, non-adapted

Remarks:

If inoculum was pre-adapted, this would be written on the report, what is not. Substance is not widely used, annual production is lower than 30 ton. It is not ubiquitous in consumer products.

Details on inoculum:

- A sample of aerobic sludge that has been selected by the mixed treatment plant of urban (about 66%) and industrial (about 34%) liquid sewage situated at San Rocco - Monza (MI).
- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): A sample of aerobic sludge that has been selected by the mixed treatment plant of urban (about 66%) and industrial (about 34%) liquid sewage situated at San Rocco - Monza (MI). Inoculum was not preadapted. See attached report for more information.
-In the laboratory the sampled mudshave been mixed and let settle, keeping them in aerobic conditions. The mud samples, before their use, have been analysed to checkits ability to form colony.
Bacterial count in the ud was 1.99x10exp6 cell/ml (see Colony report attached).
10.4 ml of this mud were put in 10000 ml and then in the final vessels of test there were 1:1000 of the starting mud , so 10exp3cell/ml.

Duration of test (contact time):

28 d

Initial conc.:

20.78 mg/L

Based on:

TOC

Parameter followed for biodegradation estimation:

other: total inorganic carbon (TIC)

Remarks:

with a TOC analyser

Details on study design:

Bottles preparation:
- Medium preparation.
- 20 bottles for the test substance, for the blank, and for the reference substance to which the inoculum of the muds has been added (in five replicate bottles).
Everything was done using deionized water.
- Incubation at 25 +/- 2°C for 28 days (under stirring in darkness).

Reference substance:

benzoic acid, sodium salt

Remarks:

Purity 99%, used at a nominal concentration of 20.22 mg/L of organic carbon (TOC)

Key result

Parameter:

% degradation (inorg. C analysis)

Value:

87

Sampling time:

14 d

Key result

Parameter:

% degradation (inorg. C analysis)

Value:

95

Sampling time:

28 d

Details on results:

- Total biodegradation (Dt) has been calculated using the equation:
Dt = (TICt - TICb)/TOCi*100
(TOCi = concentration of organic carbon of the test substance, in mg, added at the beginning).
- A substance is considered biodegradable when its level of biodegradability is at least 60%, within a period of 28 days.

Results with reference substance:

Percentage of biodegradation (benzoic acid, sodium salt) after 14 days: 95

Table 1. Results

Check point (days)	% of biodegradation; Reference substance	% of biodegradation; Test substance
0	0	0
1	16	14
6	101	91
14	95	87
21	96	80
28	105	95

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

Under the study conditions, the substance was considered to be readily biodegradable under aerobic conditions.

Executive summary:

A study was conducted to determine the biodegradation of the substance in water according to OECD Guideline 310 and EN ISO 10634:1995, in compliance with GLP. Aerobic sludge that has been selected by the mixed treatment plant of urban (about 66%) and industrial (about 34%) liquid sewage has been exposed to the test substance for 28 d at 25°C (under stirring in darkness). Total inorganic carbon (TIC) was measured using an automatic TOC analyser and total biodegradation (Dt) was then calculated (Dt = (TICt - TICb)/TOCi*100). The biodegradation of the test substance was 87% and 95%, after 14 and 28 d, respectively. The percentage of biodegradation for the positive control substance, i.e. benzoic acid, sodium salt after 14 d was 95. The experiment was considered valid. Under the study conditions, the substance was considered to be readily biodegradable under aerobic conditions (Giarei, 2016).

Description of key information

Readily biodegradable: 95% in 28 days (OECD 310)

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Additional information

A study was conducted to determine the biodegradation in water of the substance according to OECD guideline 310 and EN ISO 10634:1995, in compliance with GLP. Aerobic sludge that has been selected by the mixed treatment plant of urban (about 66%) and industrial (about 34%) liquid sewage has been exposed to the test substance (act. ingr. 25.5%) for 28 d at 25°C (under stirring in darkness). Total inorganic carbon (TIC) was measured using an automatic TOC analyser and total biodegradation (Dt) was then calculated (Dt = (TICt - TICb)/TOCi*100). The biodegradation of the test substance was 87% and 95%, after 14 and 28 d, respectively. The percentage of biodegradation for the positive control substance, i.e. benzoic acid, sodium salt after 14 d was 95. The experiment was considered valid. Under the study conditions, the substance was considered to be readily biodegradable under aerobic conditions (Giarei, 2016).

[Type of water: freshwater]