Disodium Capryloyl 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 20, 2015 to February 22, 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

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

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: OECD Guideline for testing of chemicals, 2006

Version / remarks:

Section 3, part 1

GLP compliance:

yes (incl. QA statement)

Remarks:

Quality Assurance statement is at page 4 of the report

Specific details on test material used for the study:

Batch no.: 145
Dry matter: 37.6% in water (water to 100%)
Purity: 90.4% on the dry matter
Solubility: soluble in water
Being the report done before ECHA Agreement on substance name, the name on the report is L-Glutamic acid, N-(1-oxooctyl)-,sodium salt (1:2) but the substance tested is the reference substance. All raw materials used and manufacturing process are the same

Oxygen conditions:

aerobic

Inoculum or test system:

sewage, predominantly domestic, non-adapted

Remarks:

If inoculum was adapted, this would be written on the report, what is not. Substance is not widely used, annual production is lower than 10 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).
- The inoculum was prepared in order to have a concentration of suspended solid of about 4 mg/L.
- Bacterial density after 5 dilution was brought to 20 10e5
- 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, that means domestic (about 66%) and industrial (about 34%) liquid sewage situated at San Rocco - Monza (MI). Inoculum was not preadapted. See attached report for more information.

Duration of test (contact time):

28 d

Initial conc.:

20.88 mg/L

Based on:

TOC

Parameter followed for biodegradation estimation:

other: Total Inorganic Carbon (TIC) measured 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 with the nominal concentration of 20.21 mg/l of organic carbon (TOC)

Key result

Parameter:

% degradation (inorg. C analysis)

Value:

90

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: 100%

Table 1. Results

Check point (days)	% of biodegradation; Reference substance	% of biodegradation; Test substance
0	0	0
1	9	19
6	95	87
14	100	101
21	105	83
28	104	90

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 in water of the substance according to OECD Guideline 310 and EN ISO 10634:1995, in compliance with GLP. Aerobic sludge collected from a mixed treatment plant of urban (about 66%) and industrial (about 34%) liquid sewage was exposed to the test substance (act. ingr. 37.6%) for 28 days at 25 +/- 2°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 90% after 28 days. The percentage of biodegradation for the positive control substance, i.e. benzoic acid, sodium salt after 14 days was 100. The experiment was valid. Under the study conditions, the substance was considered to be readily biodegradable under aerobic conditions (Giarei, 2016).

Description of key information

Test used was OECD 310-2006. Even if on the report the name L-Glutamic acid, N-(1-oxooctyl)-,sodium salt (1:2) appears, the substance used is the same as the reference substance. All raw materials used and manufatuing process are the same. Name was changed after ECHA agreement to improve identification.

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Type of water:

other: Demi water

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 collected from a mixed treatment plant of urban (about 66%) and industrial (about 34%) liquid sewage was exposed to the test substance (act. ingr. 37.6%) for 28 days at 25 +/- 2°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 90% after 28 days. The percentage of biodegradation for the positive control substance, i.e. benzoic acid, sodium salt after 14 days was 100. The experiment was valid. Under the study conditions, the substance was considered to be readily biodegradable under aerobic conditions (Giarei, 2016).

 

[Type of water: freshwater]