Soybean oil, epoxidized

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:

22/09/88 - 20/10/88

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Not much information on full method. May not be GLP compliant. Very minor deviations

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1988

Report date:

1988

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Deviations:

yes

Remarks:

Please see Overall Remarks

Principles of method if other than guideline:

Determination of the biodegradability by measurement of the carbon dioxide formation in per cent of ThCO2 calculated from the ThOC or TOC

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Epoxidized soybean oil

IUPAC Name:

Epoxidized soybean oil

Constituent 2

Reference substance name:

Soybean oil, epoxidized

EC Number:

232-391-0

EC Name:

Soybean oil, epoxidized

Cas Number:

8013-07-8

Molecular formula:

Not necessary, substance is a UVCB.

IUPAC Name:

Soybean oil, epoxidized

Constituent 3

Reference substance name:

Reoplast 392 (Reoplast 39)

IUPAC Name:

Reoplast 392 (Reoplast 39)

Constituent 4

Reference substance name:

TK 11278

IUPAC Name:

TK 11278

Details on test material:

- Name of test material (as cited in study report): TK 11278
- Physical state: Liquid
- Analytical purity: comm. grade
- Lot/batch No.: 22.07.88
- Stability under test conditions: 08/93
- Storage condition of test material: At room temperature
- Solubility: insoluble in water

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
Not relevant

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge (adaptation not specified)

Details on inoculum:

Bacteria were collected from activated sludge from a sewage treatment plant located in Reinhach

Duration of test (contact time):

28 d

Initial test substance concentration

Initial test substance concentration 1

Initial conc.:

10 mg/L

Based on:

test mat.

Initial test substance concentration 2

Initial conc.:

20 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

CO2 evolution

Details on study design:

TEST CONDITIONS
1200 ml of the mineral solution with the inoculum were aerated for 24 hours in the test vessel. In 300 ml mineral solution 0.5 ml Nonylphenol 10E05PO (solution of 31.2 mg in 100 ml bidist. water) and 15 rsp. 30 mg of test substance were added and homogenised. This solution was given to the test vessel which was immediately connected to the CO2 traps.
10 mg test substance are equivalent to 7.12 mg organic carbon.
- Test temperature: 22 ± 2 °C
- Aeration of dilution water: 25 ml/min of carbon dioxide free air

TEST SYSTEM
- Culturing apparatus: 2 L flasks equipped with gas inlet and magnetic stirrer

SAMPLING
Determination of the initial CO2 of the 0.05N sodium hydroxide and the CO2 absorbed in the absorbers filled with 200 ml 0.05N sodium hydroxide on the days 5, 11, 18, 22, 27 and 28.

CONTROL AND BLANK SYSTEM
Blank + Vehicle: Water as specified in the guideline containing 0.5 ml of the Nonylphenol solution (for calculation of biodegradation).
Blank: Water as specified in the guideline.


STATISTICAL METHODS:
The biodegradation was calculated on the basis of the theoretical carbon content of the test substance and the cumulative quantities of carbon dioxide determined on the days of measurements.

Reference substance

Reference substance:

aniline

Remarks:

20 mg/L, MERCK No.: 1261

Results and discussion

Preliminary study:

No results stated

Test performance:

Not stated

% Degradation

% Degradation 1

Parameter:

% degradation (CO2 evolution)

Value:

79

Sampling time:

28 d

Remarks on result:

other: 10 mg test substance/L

% Degradation 2

Parameter:

% degradation (CO2 evolution)

Value:

92

Sampling time:

28 d

Remarks on result:

other: 20 mg test substance/L

Details on results:

The biodegradation calculated as percentage of measured amount of CO2 over the theory was:
10 mg test substance/L = 79 % in 28 days
20 mg test substance/L = 92 % in 28 days

Please see table 1 for further details
Therefore, TK11278 is readily biodegradable.

BOD5 / COD results

Results with reference substance:

The biodegradation was calculated as: 20 mg/L = 94.4 % in 28 days

Any other information on results incl. tables

Theoretical CO2 formation:

Reference Substance:                                                        20 mg/L = 85.061 mg CO2/1.5L

Test Substance:                                                                  10 mg/L = 39.13 mg CO2/1.5L

Test Substance:                                                                  20 mg/L = 78.26 mg CO2/1.5L

Table 1: CO2 Evolution and Biodegradation

DAY	Blank		Blank and vehicle		Aniline (Ref. Substance) 20 mg/L				Test Substance at 10 mg/L				Test Substance at 20 mg/L
	CO2 Evolution		CO2 Evolution		CO2 Evolution		Biodegradation		CO2 Evolution		Biodegradation		CO2 Evolution		Biodegradation
	[mg]	[mg]*	[mg]	[mg]*	[mg]	[mg]*	[%]	[%]*	[mg]	[mg]*	[%]	[%]*	[mg]	[mg]*	[%]	[%]*
5	2.7	2.7	4.2	4.2	16.1	16.1	19.0	19.0	16.3	16.3	41.8	42	42.1	42.1	53.8	54
11	6.4	9.2	6.1	10.3	47.3	63.4	55.6	74.5	10.3	26.7	26.4	68	19.0	61.1	24.3	78
18	7.6	16.8	7.7	18.0	7.2	70.6	8.4	83.0	3.0	29.7	7.7	76	6.5	67.6	8.3	86
22	3.7	20.4	4.0	22.0	3.8	74.4	4.5	87.4	-0.4	29.3	-0.9	75	0.1	67.7	0.1	87
27	7.3	27.7	5.6	27.6	5.9	80.2	6.9	94.3	1.5	30.9	3.9	79	3.4	71.2	4.4	91
28	1.2	28.9	1.7	29.3	0.1	80.3	0.1	94.4	-0.1	30.8	-0.2	79	1.2	72.3	1.5	92

* = cumulative values

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

TK11278 is readily biodegradable.

Executive summary:

A ready biodegradability test (OECD guideline 301B) was conducted on TK 11278 (otherwise known as Reoplast 39 or epoxidised soybean oil) using bacteria from a sewage treatment plant. Aniline was used as a reference substance.

After 28 days:

The biodegradation calculated as percentage of measured amount of CO2 over the theory was:

10 mg test substance/L = 79 % in 28 days

20 mg test substance/L = 92 % in 28 days

The % degradation (% ThCO2 formation) exceeded 10% within 2 to 3 days for both concentrations of the test material and subsequently exceeded the 60% pass level within the 10 day window.

Therefore, epoxidised soybean oil is readily biodegradable.