Glycerides, tallow sesqui-, hydrogenated, propoxylated

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:

Study conducted 24 November to 23 December 2015

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: RL 686/15
- Expiration date of the lot/batch: 30 October 2018
- Purity test date: Complex mixture

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Room temperature
- Stability under test conditions: No data
- Solubility and stability of the test substance in the solvent/vehicle: Low solubility in aqueous media
- Reactivity of the test substance with the solvent/vehicle of the cell culture medium: No data

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): Worlingworth sewage treatment works, Suffolk, UK
- Storage conditions: aerated
- Storage length: No data
- Pretreatment: No
- Concentration of sludge: 30 mg/L

Duration of test (contact time):

<= 28 d

Initial conc.:

<= 50 mg/L

Based on:

test mat.

Remarks:

Test item solvent stock solution prepared by dissolving test item in tetrahydrofuran (THF), followed by dilution in acetone. An aliquot added to test vessels

Parameter followed for biodegradation estimation:

CO2 evolution

Details on study design:

TEST CONDITIONS
- Composition of medium:
- Additional substrate:
- Solubilising agent (type and concentration if used):
- Test temperature:
- pH:
- pH adjusted: yes/no
- CEC (meq/100 g):
- Aeration of dilution water:
- Suspended solids concentration:
- Continuous darkness: yes/no
- Other:

TEST SYSTEM
- Culturing apparatus:
- Number of culture flasks/concentration:
- Method used to create aerobic conditions:
- Method used to create anaerobic conditions:
- Measuring equipment:
- Test performed in closed vessels due to significant volatility of test substance:
- Test performed in open system:
- Details of trap for CO2 and volatile organics if used:
- Other:

SAMPLING
- Sampling frequency:
- Sampling method:
- Sterility check if applicable:
- Sample storage before analysis:
- Other:

CONTROL AND BLANK SYSTEM
- Inoculum blank:
- Abiotic sterile control:
- Toxicity control:
- Other:

STATISTICAL METHODS:

Key result

Parameter:

% degradation (CO2 evolution)

Value:

>= 63

Sampling time:

28 d

Details on results:

The test item can be classed as a substance of unknown or variable composition, therefore, under EC regulation 286/2011 the 60% pass level can be determined after 28 days and the 10-day window pass level can be waived. The test item showed 63% biodegradation at the end of the test (Day 28) and may be considered readily biodegradable under the conditions of the test.

Day	% Biodegradation
	Test item	Toxicity control	Reference item
0	0	0	0
5	35	77	72
10	49	86	80
15	55	88	84
20	59	88	85
25	62	88	86
28	63	89	86

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

The test item can be classed as a substance of unknown or variable composition, therefore, under EC regulation 286/2011 the 60% pass level can be determined after 28 days and the 10-day window pass level can be waived. The test item showed 63% biodegradation at the end of the test (Day 28) and may be considered readily biodegradable under the conditions of the test. The reference item attained 83% biodegradation after 14 days and 86% biodegradation after 28 days confirming that sewage sludge inoculum was responding normally. The toxicity control attained 88% biodegradation after 14 days and 89% biodegradation after 28 days indicating the test item was not toxic to the sewage treatment micro-organisms used in the test.

Executive summary:

A study was performed to determine the ready biodegradabilty of the test item when exposed to sewage treatment micro-organisms under aerobic conditions. The test was conducted according to the principles of GLP and followed internationally accepted test guidelines.

Sewage sludge was exposed to an aqueous dispersion of the test item at the nominal test concentration of 50 mg/L over a period of 28 days. The respiration rate (CO2 evolution) was measured daily throughout the test period and the % biodegradation calculated. The test validity criteria were met and the study is therefore acceptable. The reference item attained 83% biodegradation after 14 days indicating the test inoculum was responding normally. The toxicity control attained 88% biodegradation after 14 days indicating the test item was not toxic to the sewage treatment micro-organisms used in the test.

The test item can be classed as a substance of unknown or variable composition, therefore, under EC regulation 286/2011 the 60% pass level can be determined after 28 days and the 10-day window pass level can be waived. The test item attained 63% biodegradtaion after 28 days and can be considered readily biodegradable under the conditions of the test.

Description of key information

The test item can be classed as a substance of unknown or variable composition, therefore, under EC regulation 286/2011 the 60% pass level can be determined after 28 days and the 10-day window pass level can be waived.  The test item showed 63% biodegradation at the end of the test (Day 28) and may be considered readily biodegradable under the conditions of the test.  The reference item attained 83% biodegradation after 14 days confirming that sewage sludge inoculum was responding normally.  The toxicity control attained 89% biodegradation after 28 days indicating the test item was not toxic to the sewage treatment micro-organisms used in the test.

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Type of water:

freshwater