Bottom residues resulting from the synthesis of propylene oxide and styrene from epoxidation of propylene with ethylbenzene hydroperoxide

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:

Jan-Jun 2011

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: study performed according to OECD guideline and GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2011

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Bottom product of propylene oxide and styrene production

IUPAC Name:

Bottom product of propylene oxide and styrene production

Details on test material:

- Name of test material (as cited in study report): KORE grade V
- Substance type: UVCB
- Physical state: Brown viscous liquid
- Stability under test conditions: months
- Storage condition of test material: room temperature

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

Prior to use a sample of activated sludge from the sewage plant at Taunusstein-Bleidenstadt was washed twice with mineral nutrient solution of the CO2-Evolution-Test to eliminate organic components and carbonates from the sludge. After resolution with mineral nutrient medium the sludge was aerated by means of compressed humidified air for about four hours. Before use as inoculum for the CO2-Evolution-Test the sludge was homogenised in a "Waring Blender" at low speed for 2 minutes and then filtered through a cotton filter previously carefully rinsed with deionised water. The filtrate was used as inoculum (1% of the final volume of the test solution) on the same day of preparation.

Duration of test (contact time):

ca. 28 d

Initial test substance concentration

Initial test substance concentration 1

Initial conc.:

103.3 mg/L

Based on:

test mat.

Initial test substance concentration 2

Initial conc.:

104.4 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

TEST CONDITIONS
- Composition of medium: as mentioned in the guideline
- Additional substrate: none
- Solubilising agent: none
- Test temperature: values were in the range of 19.6 to 21.3 °C (mean 20.1°C)
- pH: 7.4 ± 0.2 at t0
- pH adjusted: no
- Aeration of dilution water: the aeration rate of the test system was controlled at 4 L/h
- Continuous darkness: yes

TEST SYSTEM
- Culturing apparatus: ≈5-litre amber carboys served as test vessels. They were closed with stoppers with tubing for gas inlet and outlet (gas exit line)
- Number of culture flasks/concentration: two vessel with the test item, one vessel with sodiumbenzoate (control item), one toxicity control
- Method used to create aerobic conditions: aeration

SAMPLING
- Sampling frequency: Titrations were performed at t3d, t5d, t10d, t14d, t20d, t28d, and t29d
- Sample storage before analysis: data not available

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

STATISTICAL METHODS: not applicable

Reference substance

Reference substance:

benzoic acid, sodium salt

Remarks:

20 mg TOC/L

Results and discussion

% Degradation

Parameter:

other: O2 uptake in the test solutions

Value:

50.8

Sampling time:

28 d

Remarks on result:

other: mean value

Details on results:

The degradation process was followed by the oxygen uptake in the test solutions using two test solutions of the test item. With respect to the theoretical oxygen demand (ThOD) of the test item and the measured BOD of the test solutions a degradation value of 53% of the test item was measured within the first test solution using 103.3 mg/L of the test item after 28 days of incubation. 48.6% degradation was observed in the second test solution with 104.0 mg/L test item.
The calculated mean degradation value of the test item was 50.8 %.

BOD5 / COD results

Results with reference substance:

The control item sodium benzoate was degraded 88 %, the "10-days-window" being met within 5 days (68 %).

Any other information on results incl. tables

Degradation of the Test Item in the 1^stTest Solution, 103.3 mg/L

Time (d)	Values read on the Display of the Respirometer (mg O2/L)^1)			% Degradation
	Blank 1	Blank 2^2)	Test Item
0.0	0	0	0	0.0
1.0	0	0	0	0.0
2.0	0	0	0	0.0
3.0	0	0	85	9.3
3.9	1	0	159	17.4
4.9	4	0	242	26.2
5.9	6	0	270	29.0
7.0	8	0	295	31.6
7.9	10	0	313	33.3
8.8	11	0	326	34.6
10.1	13	0	338	35.7
11.0	14	0	354	37.4
12.0	15	0	367	38.7
12.9	16	0	379	39.9
13.9	18	0	394	41.3
14.9	19	0	408	42.8
15.9	20	0	424	44.4
16.8	21	0	434	45.4
17.9	23	0	446	46.5
19.0	23	0	458	47.8
20.0	24	0	465	48.5
20.9	25	0	472	49.2
22.0	28	0	479	49.6
22.9	28	0	485	50.3
24.1	28	0	494	51.2
25.0	29	0	497	51.5
25.9	30	0	504	52.1
27.0	31	0	508	52.5
28.0	33	0	517	53.2

¹⁾The indicated values are multiplied by factor 0.25 which is valid for the 1000 mL of volume.

²⁾not considered as there was an equipment error.  

 

Degradation of the Test Item in the 2^ndTest Solution, 104.0 mg/L

Time (d)	Values read on the Display of the Respirometer (mg O2/L)^1)			% Degradation
	Blank 1	Blank 2^2)	Test Item
0.0	0	0	0	0.0
1.0	0	0	0	0.0
2.0	0	0	35	3.8
3.0	0	0	103	11.3
3.9	1	0	184	20.0
4.9	4	0	245	26.3
5.9	6	0	271	28.9
7.0	8	0	288	30.6
7.9	10	0	296	31.2
8.8	11	0	306	32.2
10.1	13	0	324	34.0
11.0	14	0	336	35.2
12.0	15	0	350	36.6
12.9	16	0	362	37.8
13.9	18	0	374	38.9
14.9	19	0	384	39.9
15.9	20	0	394	40.9
16.8	21	0	402	41.6
17.9	23	0	411	42.4
19.0	23	0	420	43.4
20.0	24	0	426	43.9
20.9	25	0	433	44.6
22.0	28	0	442	45.2
22.9	28	0	446	45.7
24.1	28	0	454	46.5
25.0	29	0	459	47.0
25.9	30	0	465	47.5
27.0	31	0	469	47.8
28.0	33	0	478	48.6

¹⁾The indicated values are multiplied by factor 0.25 which is valid for the 1000 mL of volume.

²⁾not considered as there was an equipment error.

Degradation of the Toxicity Control

Time (d)	Values read on the Display of the Respirometer (mg O2/L)^2)			% Degradation^1)
	Blank 1	Blank 2^3)	Toxicity Control
0.0	0	0	0	0.0
1.0	0	0	62	3.8
2.0	0	0	258	15.6
3.0	0	0	322	19.5
3.9	1	0	383	23.2
4.9	4	0	477	28.9
5.9	6	0	609	36.8
7.0	8	0	633	38.2
7.9	10	0	643	38.7
8.8	11	0	661	39.7
10.1	13	0	688	41.3
11.0	14	0	691	41.5
12.0	15	0	712	42.7
12.9	16	0	727	43.6
13.9	18	0	728	43.6
14.9	19	0	731	43.7
15.9	20	0	739	44.2
16.8	21	0	741	44.3
17.9	23	0	743	44.3
19.0	23	0	744	44.4
20.0	24	0	745	44.4
20.9	25	0	763	45.5
22.0	28	0	800	47.6
22.9	28	0	815	48.5
24.1	28	0	822	49.0
25.0	29	0	836	49.8
25.9	30	0	845	50.3
27.0	31	0	885	52.7
28.0	33	0	890	52.9

 

¹⁾The basis for the biodegradation is the sum of ThODs of both the test item and sodium benzoate.

²⁾ The indicated values are multiplied by factor 0.5 which is valid for the 500 mL of volume.

³⁾not considered as there was an equipment error.

With respect to the theoretical oxygen demand (ThOD) of the test item and the measured BOD of the test solutions a degradation value of 53% of the test item was measured within the first test solution using 103.3 mg/L of the test item after 28 days of incubation. 48.6% degradation was observed in the second test solution with 104.0 mg/L test item.The toxicity control showed >25% degradation within 14 days based on total ThOD, therefore the test substance is not considered to be inhibitory according to the OECD test guidelines 301.Regarding the results obtained within this study the test item should be considered "not readily biodegradable". The control item sodium benzoate was degraded 98% within 28d. The threshold of³60% was met within 5d (60.8%) of incubation. Therefore, the test is considered valid. An abiotic degradation can be excluded.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

other: not readily biodegradable

Conclusions:

The test substance is not considered to be inhibitory.
The test item should be considered "not readily biodegradable"

Executive summary:

”KORE grade V“was tested for biodegradability according to ‘Manometric Respirometry Test' (OECD Guideline 301F).The degradation process was followed by the oxygen uptake in the test solutions using two test solutions of the test item. With respect to the theoretical oxygen demand (ThOD) of the test item and the measured BOD of the test solutions a degradation value of 53% of the test item was measured within the first test solution using 103.3 mg/L of the test item after 28 days of incubation. 48.6% degradation was observed in the second test solution with 104.0 mg/L test item.The toxicity control showed >25% degradation within 14 days based on total ThOD, therefore the test substance is not considered to be inhibitory according to the OECD test guidelines 301.Regarding the results obtained within this study the test item should be considered "not readily biodegradable". The control item sodium benzoate was degraded 98% within 28d. The threshold of³60% was met within 5d (60.8%) of incubation. Therefore, the test is considered valid. An abiotic degradation can be excluded.