bis[2-(4,4-dimethylpentan-2-yl)-5,7,7-trimethyloctyl] (2E)-but-2-enedioate

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:

From 5/13/2013 to 07/03/2013

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Experiment conducted following OECD guidelines, under GLP.

Cross-reference

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.4-C (Determination of the "Ready" Biodegradability - Carbon Dioxide Evolution Test)

Deviations:

no

Principles of method if other than guideline:

not applicable

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

bis[2-(4,4-dimethylpentan-2-yl)-5,7,7-trimethyloctyl] (2E)-but-2-enedioate

EC Number:

700-897-5

Molecular formula:

C40H76O4

IUPAC Name:

bis[2-(4,4-dimethylpentan-2-yl)-5,7,7-trimethyloctyl] (2E)-but-2-enedioate

Test material form:

other: Clear colorless liquid

Details on test material:

- Substance type: clear colorless liquid
- Physical state: liquid
- Analytical purity: > 99%
- Storage condition of test material: at room temperature in the dark

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
no data

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic (adaptation not specified)

Details on inoculum:

- Laboratory culture: Mixed population of activated sewage sludge micro-organisms was obtained from the aeration stage of the Severn Trent Water Plc sewage treatment plant at Loughborough, Leicestershire, UK, which treats predominantly domestics sewage.
- Method of cultivation: Maintained on continuous aeration in the laboratory at a temperature of 21°C and was used on the day of collection.
- Preparation of inoculum for exposure: The sludge was washed 2 times by settlement and resuspension in culture medium to remove any excessive amounts of dissolved organic carbon that may have been present.
- Pretreatment: no data
- Initial biomass concentration: 3.2g/L priori to use

Duration of test (contact time):

28 d

Initial test substance concentration

Initial test substance concentration 1

Initial conc.:

10 other: mgC/L

Based on:

DOC

Initial test substance concentration 2

Initial conc.:

5 other: mgC/L

Based on:

DOC

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

CO2 evolution

Details on study design:

TEST CONDITIONS
- Composition of medium: standard
- Additional substrate: none
- Solubilising agent (type and concentration if used): none
- Test temperature: 21°C
- pH: 7.4-7.6
- pH adjusted: yes
- CEC (meq/100 g): no data
- Suspended solids concentration: 30mg/L
- Aeration of dilution water: yes
- Continuous darkness: yes

TEST SYSTEM
- Culturing apparatus: 5L test culture vessels
- Number of culture flasks/concentration: 2
- Method used to create aerobic conditions: aerated with CO2-free air.
- Test performed in closed vessels due to significant volatility of test substance: yes
- Test performed in open system: no
- Details of trap for CO2 and volatile organics if used: CO2-free air was produced by passing compressed air through a glass column containing soda lime (Carbosorb) granules.. The CO2 produced by degradation was collected in two 500 mL Dreschel bottles containing 350 mL of 0.05 M NaOH.
- Other: none
SAMPLING
- Sampling frequency: at day 0, 1, 2, 3, 6, 8, 10, 14, 21, 28, 29
- Sampling method: samples were injected into the IC channel of the TOC analyser. Each analysis was carried out in triplicate.
- Sterility check if applicable: no data
- Sample storage before analysis: none

CONTROL AND BLANK SYSTEM
- Inoculum blank: yes
- Abiotic sterile control: no data
- Toxicity control: yes

Reference substance

Reference substance:

benzoic acid, sodium salt

Results and discussion

Preliminary study:

none

Test performance:

no data

% Degradation

Parameter:

% degradation (CO2 evolution)

Value:

2

Sampling time:

28 d

Details on results:

The test item attained 2% degradation after 28 days and therefore cannot be considered to be readily biodegradable under the strict terms and conditions of OECD Guideline No. 301B.
The toxicity control attained 53% degradation after 14 days and 54% degradation after 28 days thereby confirming that the test item was not toxic to the sewage treatment micro-organisms used in the test.
Sodium benzoate attained 61% degradation after 14 days and 72% degradation after 28 days thereby confirming the suitability of the inoculum and test conditions.

BOD5 / COD results

Results with reference substance:

Sodium benzoate attained 61% degradation after 14 days, and 72% degradation after 28 days, confirming the suitability of the inoculum and test conditions.

Any other information on results incl. tables

Table 1         PercentageBiodegradationValues

 

Day	%DegradationSodiumBenzoateProcedureControl	%Degradation TestItem	%DegradationTestItemplusSodium BenzoateToxicity Control
0	0	0	0
2	41	10	29
6	59	13	48
8	65	8	44
10	71	8	45
14	61	0	53
21	75	0	51
28	79	12	57
29	72	2	54

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

under test conditions no biodegradation observed

Conclusions:

The test material attained 2% degradation after 28 days.

Executive summary:

Test Guidance

A study was conducted following OECD guidelines 301B, and EU Method C.4 -C, under GLP conditions.

Method and Material

The test material, at a concentration of 5mg carbon/L , was exposed to activated sewage sludge micro-organisms with culture medium in sealed culture vessels in the dark at 21°C for 28 days.

Results

The test material attained 2% degradation after 28 days.

The toxicity control attained 53% degradation after 14 days and 54% degradation after 28 days thereby confirming that the test item was not toxic to the sewage treatment micro-organisms used in the test.

Sodium benzoate attained 61% degradation after 14 days and 72% degradation after 28 days thereby confirming the suitability of the inoculum and test conditions.

Conclusion

The test material is readily biodegradable.