Fatty acids, C8-10, diesters with 1,4:3,6-dianhydro-D-glucitol

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 September 28,2007 to October 26,2007

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: recent report; GLP conditions; OECD guideline followed

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2007

Report date:

2007

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Deviations:

yes

Remarks:

In addition, degradation was followed by T.O.C. analysis at frequent intervals over the 28 days period. This measurement of carbon content was considered as not relevant due to the behaviour of the test item in the test medium.

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Isosorbide Diesters

EC Number:

700-073-5

Cas Number:

1215036-04-6

Molecular formula:

As it is an UVCB, we can not provide the exact molecular formula.

IUPAC Name:

Isosorbide Diesters

Details on test material:

- Name of test material (as cited in study report): LAB 3822
- Physical state: liquid
- Lot/batch No.: FAL 07/25
- Expiration date of the lot/batch: 2009
- Storage condition of test material: at room temperature but preferably between 10 and 15°C

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic (adaptation not specified)

Details on inoculum:

The inoculum was prepared from activated sludge sampled in the aeration tank treatment plant receiving predominantly domestic sewage (Montataire - (60) France). The supernatant of this activated sludge was used as inoculum.

Duration of test (contact time):

28 d

Initial test substance concentration

Initial test substance concentration 1

Initial conc.:

10 mg/L

Based on:

DOC

Initial test substance concentration 2

Initial conc.:

20 mg/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: abiotic
- Test temperature: regulated room ,20-23°c
- mineral medium pH: 7.45
- Aeration of dilution water: carbon dioxide-free air
- Continuous darkness: yes



TEST SYSTEM
- Culturing apparatus:
- Number of culture flasks/concentration: 8
- Method used to create aerobic conditions: carbon dioxide-free air
- Measuring equipment: carbon analyser : Shimadzu TOC VSCN and SSM 5000A
- Test performed in open system: yes
- Details of trap for CO2 and volatile organics if used: CO2 is trapped as BaCO3 in barium hydroxide (Ba(OH)2) and is measured by titration of the residual 0.0125 M Ba(OH)2 with a 0.05M HCL solution in presence of phenolphtalein.
- Frequency : each of 2 or 3 days



CONTROL AND BLANK SYSTEM
- blank control : only inoculum
- inoculum control:aniline 20mg/l + inoculum
- Toxicity control: HgCl2

Reference substance

Reference substance:

aniline

Results and discussion

% Degradation

Parameter:

% degradation (CO2 evolution)

Value:

83

Sampling time:

28 d

Details on results:

The pass level for ready biodegradability, 60% of ThCO2, has been reached in a 10-d window and the CO2 production in the test suspension is relatively gradually during the test period.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

The level of degradation of the LAB 3822 has reached 83% ThCO2 within a 28 day-period, criteria for good evidence of "ready biodegradability" were respected in test conditions.

Executive summary:

The biodegradability of LAB3822 is evaluated by the determination of the carbon dioxide produced by the test item degradation. The test method is OECD Guideline for the testing of chemicals 301 B: CO2 Evolution Test (17 july 1992). The test concentrations are 10 and 20 mg/l as organic carbon (O.C.) (nominal, initial concentrations). The reference item is aniline, 20mg/l (O.C.). Inoculum is prepared from activated sludge from a treatment plant receiving predominantly domestic sewage. The duration is 28 days.

RESULTS :

LAB 3822		ANILINE
10mg C/L	20mg C/L	20mg C/L
79.1%	86.2%	97%
Mean : 83%		/

The level of degradation of the LAB 3822 has reached 83% ThCO2 within a 28 day-period, criteria for good evidence of "ready biodegradability" were respected in test conditions.