Bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate

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:

October 10, 1991 - October 29, 1991

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Qualifier:

according to guideline

Guideline:

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

Deviations:

yes

Remarks:

, see "principles of method if other..."

Principles of method if other than guideline:

The volume of test solution was reduced from 3.0 to 1.5 L.
An emulsifier (Tween 80) was used and an appurtenant solvent control was conducted. A blank control was not applied.

GLP compliance:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge (adaptation not specified)

Details on inoculum:

Bacteria collected from activated sludge of the sewage treatment plant of CH-4153 Reinach on September 30, 1991. The pH after collection was 7.0.
The preparation was carried out according to the guideline EU C.5.

Duration of test (contact time):

28 d

Initial conc.:

20.3 mg/L

Based on:

test mat.

Initial conc.:

10.7 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

CO2 evolution

Remarks:

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

Details on study design:

Design and procedure:
- Vessels: 2 L flasks (dark brown glass) equipped with gas inlet and magnetic stirrer
- Water: The test medium was prepared according to the method described in EU C.5.
- Temperature: 22+/-2°C
- Duration: 28 days
- Air: approximately 25 mL/min purified from carbon dioxide

Test substance preparation:
- 1200 mL of the mineral solution with the inoculum were aerated for 24 hours in the test vessel. In 300 mL mineral solution 15 mL Polyoxyethylen-Sorbitan-Monooleate (TWEEN 80) (FLUKA 93781) (solution of 30 mg in 100 mL bidist. water) and 16.0 rsp 30.5 mg of test substance were added and homogenized. This solution was given to the test vessel which was immediately connected to the CO2 traps.

Reference substance: 20 mg/L
Blank: water with inoculum containing 15 mL of the Tween 80 solution

Measurements:
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 3, 6, 10, 13, 17, 20, 24, 27 and 28.

Reference substance:

aniline

Remarks:

Concentration: 20 mg/L, Aniline Merck No. 1261, Batch: 06/91, Stability: 12/91

Parameter:

% degradation (CO2 evolution)

Value:

10

Sampling time:

28 d

Remarks on result:

other: Initial concentration: 10.7 mg/L

Parameter:

% degradation (CO2 evolution)

Value:

24

Sampling time:

28 d

Remarks on result:

other: Initial concentration: 20.3 mg/L

Details on results:

Mean % biodegradation corrected for blank: 17%
Differences in replicate values at end of test: 14%

Results with reference substance:

78% biodegradation, passing 10-day window

Interpretation of results:

other: not readily biodegradable

Description of key information

The test substance is poorly biodegradable (not readily biodegradable according to OECD criteria). AN OECD TG 301B study was performed with the test item. initial conc. were 10.7 mg/L and 20.3 mg/L an emulsifier (Tween 80) was used. A degradation of 10% and 24% was shown.

Additionally, the metabolites of the hydrolysis were assessed. Sebacic acid is readily biodegradable and 2,2,6,6-tetramethylpiperidin-4-ol is not classified as PBT substance.

 

 

Key value for chemical safety assessment

Biodegradation in water:

inherently biodegradable

Type of water:

freshwater

Additional information

QSAR-disclaimer

 In Article 13 of Regulation (EC) No 1907/2006, it is laid down that information on intrinsic properties of substances may be generated by means other than tests, provided that the conditions set out in Annex XI (of the same Regulation) are met.

 

According to Annex XI of Regulation (EC) No 1907/2006 (Q)SAR results can be used if (1) the scientific validity of the (Q)SAR model has been established, (2) the substance falls within the applicability domain of the (Q)SAR model, (3) the results are adequate for the purpose of classification and labeling and/or risk assessment and (4) adequate and reliable documentation of the applied method is provided.

The criteria listed in Annex XI of Regulation (EC) No 1907/2006 are considered to be adequately fulfilled and, therefore, the endpoint(s) sufficiently covered and suitable for risk assessment.

Parent compound:

To assess the biodegradation potential of bis(2,2,6,6-tetramethylpiperidin-4-yl) sebacate (Tinuvin, CAS 52829-07-9), a GLP-study was conducted according to OECD guideline 301B (ready biodegradability test, CO2 Evolution Test). Municipal non-adapted activated sludge was used as inoculum (BASF AG, 1991, report no. 918191). After 28 days, the O2-consumption and DOC removal were below 10% and 24%, respectively.

These values are supported by the result of a study, conducted according to OECD 301E (Ready biodegradability: modified OECD screening study). A mixture of non-adapted polyvalent bacteria was used as inoculum for this study. After 29 days, the DOC removal was determined to be 29% (BASF AG, 1983, rep. no.:83122).

Therefore, the substance is considered to be poorly biodegradable (not readily biodegradable according to OECD criteria).

Experimental results are supported by two estimation models CATALOGIC: 301C v11.15 and 301F v13.16 (OASIS Catalogic v5.13.1). The CATALOGIC 301C model predicted that the substance would be degraded to 33% after 28 d based on oxygen consumption (BASF SE, 2019). The substance was completely within the applicability domain. The second estimation model predicted the substance was degraded to 29% DOC after 29 d. The substance was not completely within the applicability domain (100% parametric domain, 94% structural domain; 100% metabolic domain). However, the deviation within the strutural domain is small and the use of the model to predict potential metabolites of the substance seems justified.

 

Metabolites:

CATALOGIC 301C v11.15 (OASIS Catalogic v5.13.1) predicted 54 metabolites, identifying 9 metabolites as relevant degradation products in terms of PBT/vPvB assessment, with an estimated quantity of ≥ 0.1% (for details see ‘Attached background material’ of the respective Endpoint Study Record). Two of the relevant metabolites were predicted to be readily biodegradable (≥ 60% after 28 days, based on BOD, OECD 301C #20 and 21). The other relevant metabolites were estimated to be not readily biodegradable (0 to 23% after 28 days, based on BOD). The substance was within the applicability domain of the estimation model. In conclusion, the majority of the predicted metabolites present in a concentration of ≥ 0.1% (equivalent to >=0.001 mol/mol parent) are estimated to be not readily biodegradable. The degradation products of Bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate (CAS 52829-07-9) which are predicted to be not readily biodegradable should be considered as potentially P/vP from a precautionary point of view, until further data become available. However, all relevant metabolites have a log Kow ≤ 3. The log Kow of the relevant metabolites ranges from -2.4 to 0.9, thereby not fulfilling the screening criteria for bioaccumulation (B/vB) as laid down in Section 3.1 of REACH Annex XIII. In conclusion, all (relevant) predicted metabolites are not expected to significantly accumulate.

#	Metabolite (no)	Smiles	Quantity [mol/mol parent]	log Kow	BOD prediction (% after 28 d)
Parent	1	CC1(C)CC(OC(=O)CCCCCCCCC(=O)OC2CC(C)(C)NC(C)(C)C2)CC(C)(C)N1	0.01049	6.5004	33
2	2	CC1(C)CC(OC(=O)CCCCCCCCC(O)=O)CC(C)(C)N1	9.486E-006	1.4396	49
3	3	CC1(C)CC(OC(=O)CCCCCCC=CC(O)=O)CC(C)(C)N1	9.486E-006	2.7246	49
4	4	CC1(C)CC(OC(=O)CCCCCCC(O)CC(O)=O)CC(C)(C)N1	9.486E-006	-0.0987	48
5	5	CC1(C)CC(OC(=O)CCCCCCC(=O)CC(O)=O)CC(C)(C)N1	9.486E-006	-0.6101	48
6	6	CC1(C)CC(OC(=O)CCCCCCC(O)=O)CC(C)(C)N1	9.486E-006	0.4574	43
7	7	CC1(C)CC(OC(=O)CCCCC=CC(O)=O)CC(C)(C)N1	9.486E-006	1.7424	43
8	8	CC1(C)CC(OC(=O)CCCCC(O)CC(O)=O)CC(C)(C)N1	9.486E-006	-1.0809	41
9	9	CC1(C)CC(OC(=O)CCCCC(=O)CC(O)=O)CC(C)(C)N1	9.486E-006	-1.5923	41
10	10	CC1(C)CC(OC(=O)CCCCC(O)=O)CC(C)(C)N1	9.486E-006	-0.5248	34
11	11	CC1(C)CC(OC(=O)CCC=CC(O)=O)CC(C)(C)N1	9.485E-006	0.7602	34
12	12	CC1(C)CC(OC(=O)CCC(O)CC(O)=O)CC(C)(C)N1	9.485E-006	-2.0631	32
13	13	CC1(C)CC(OC(=O)CCC(=O)CC(O)=O)CC(C)(C)N1	9.485E-006	-2.5745	32
14	14	CC1(C)CC(OC(=O)CCC(O)=O)CC(C)(C)N1	0.1053	-1.5070	22
15	15	CC1(C)CC(O)CC(C)(C)N1	1.662	0.9422	1
16	16	CC1(C)CC(O)CC(C)(CO)N1	0.00546	-0.1162	5
17	17	CC1(C)CC(O)CC(C)(C=O)N1	1.244E-006	-0.5473	5
18	18	CC1(C)CC(O)CC(C)(C(O)=O)N1	0.1876	-1.3195	0
19	19	CC1(C(O)=O)CC(O)CC(C)(CO)N1	0.00719	-2.3779	5
20	20	OC(=O)CCC(O)=O	0.09041	-0.7543	90
21	21	CCC(O)=O	0.004176	0.5779	100
22	24	CC(O)=O	2.965E-005	0.0868	100
23	25	CC1(C)CC(OC(=O)CCCCCCCCC(=O)OC2CC(C)(C)NC(C)(CO)C2)CC(C)(C)N1	7.547E-007	5.0356	35
24	26	CC1(C)CC(OC(=O)CCCCCCCCC(=O)OC2CC(C)(C)NC(C)(C=O)C2)CC(C)(C)N1	7.547E-007	5.0109	35
25	27	CC1(C)CC(OC(=O)CCCCCCCCC(=O)OC2CC(C)(C)NC(C)(C(O)=O)C2)CC(C)(C)N1	0.0009297	3.2398	34
26	28	CC1(C)CC(OC(=O)CCCCCCCCC(O)=O)CC(C)(C(O)=O)N1	3.727E-007	0.7925	51
27	29	CC1(C)CC(OC(=O)CCCCCCC=CC(O)=O)CC(C)(C(O)=O)N1	3.727E-007	0.5775	51
28	30	CC1(C)CC(OC(=O)CCCCCCC(O)CC(O)=O)CC(C)(C(O)=O)N1	3.727E-007	0.2531	50
29	31	CC1(C)CC(OC(=O)CCCCCCC(=O)CC(O)=O)CC(C)(C(O)=O)N1	3.727E-007	-1.2572	50
30	32	CC1(C)CC(OC(=O)CCCCCCC(O)=O)CC(C)(C(O)=O)N1	3.727E-007	-0.1897	44
31	33	CC1(C)CC(OC(=O)CCCCC=CC(O)=O)CC(C)(C(O)=O)N1	3.727E-007	-0.4047	44
32	34	CC1(C)CC(OC(=O)CCCCC(O)CC(O)=O)CC(C)(C(O)=O)N1	3.727E-007	-0.7291	43
33	35	CC1(C)CC(OC(=O)CCCCC(=O)CC(O)=O)CC(C)(C(O)=O)N1	3.726E-007	-2.2394	43
34	36	CC1(C)CC(OC(=O)CCCCC(O)=O)CC(C)(C(O)=O)N1	3.726E-007	-1.1719	35
35	37	CC1(C)CC(OC(=O)CCC=CC(O)=O)CC(C)(C(O)=O)N1	3.726E-007	-1.3869	35
36	38	CC1(C)CC(OC(=O)CCC(O)CC(O)=O)CC(C)(C(O)=O)N1	3.726E-007	-1.7113	34
37	39	CC1(C)CC(OC(=O)CCC(=O)CC(O)=O)CC(C)(C(O)=O)N1	3.726E-007	-3.2216	34
38	40	CC1(C)CC(OC(=O)CCC(O)=O)CC(C)(C(O)=O)N1	0.004136	-2.1541	23
39	41	CC(C)(O)CC(CC(C)(C)N)OC(=O)CCCCCCCCC(=O)OC1CC(C)(C)NC(C)(C)C1	6.519E-005	5.6232	35
40	42	CC(C)(O)CC(CC(C)(C)N)OC(=O)CCCCCCCCC(O)=O	2.613E-008	0.5624	53
41	43	CC(C)(O)CC(CC(C)(C)N)OC(=O)CCCCCCC=CC(O)=O	2.613E-008	1.8474	53
42	44	CC(C)(O)CC(CC(C)(C)N)OC(=O)CCCCCCC(O)CC(O)=O	2.613E-008	-0.5695	52
43	45	CC(C)(O)CC(CC(C)(C)N)OC(=O)CCCCCCC(=O)CC(O)=O	2.613E-008	-1.4873	52
44	46	CC(C)(O)CC(CC(C)(C)N)OC(=O)CCCCCCC(O)=O	2.613E-008	-0.4198	46
45	47	CC(C)(O)CC(CC(C)(C)N)OC(=O)CCCCC=CC(O)=O	2.613E-008	0.8652	46
46	48	CC(C)(O)CC(CC(C)(C)N)OC(=O)CCCCC(O)CC(O)=O	2.613E-008	-1.5517	45
47	49	CC(C)(O)CC(CC(C)(C)N)OC(=O)CCCCC(=O)CC(O)=O	2.613E-008	-2.4695	45
48	50	CC(C)(O)CC(CC(C)(C)N)OC(=O)CCCCC(O)=O	2.613E-008	-1.4020	38
49	51	CC(C)(O)CC(CC(C)(C)N)OC(=O)CCC=CC(O)=O	2.613E-008	-0.1170	38
50	52	CC(C)(O)CC(CC(C)(C)N)OC(=O)CCC(O)CC(O)=O	2.613E-008	-2.5339	36
51	53	CC(C)(O)CC(CC(C)(C)N)OC(=O)CCC(=O)CC(O)=O	2.613E-008	-3.4517	36
52	54	CC(C)(O)CC(CC(C)(C)N)OC(=O)CCC(O)=O	0.00029	-2.3842	26
53	55	CC(C)(O)CC(O)CC(C)(C)N	0.004409	0.4714	3
54	56	CC(C)(N)CC(O)CC(C)(O)CO	0.0005267	-0.9934	28

Another model CATALOGIC 301F v13.16 (OASIS Catalogic v5.13.1) predicted 26 metabolites, identifying 5 metabolites as relevant degradation products in terms of PBT/vPvB assessment, with an estimated quantity of ≥ 0.1% (for details see ‘Attached background material’ of the respective Endpoint Study Record). Two of the relevant metabolites were calculated to be readily biodegradable (≥ 60% after 28 days, based on BOD, OECD 301F #26 and 27). The other relevant metabolites were estimated to be not readily biodegradable (0 to 4% after 28 days, based on BOD). The substance was not wothin tha applicability domain of the estimation model. In conclusion, the majority of the predicted metabolites present in a concentration of ≥ 0.1% (equivalent to >=0.001 mol/mol parent) are estimated to be not readily biodegradable. The degradation products of Bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate (CAS 52829-07-9) which are predicted to be not readily biodegradable should be considered as potentially P/vP from a precautionary point of view, until further data become available. However, all relevant metabolites have a log Kow ≤ 3. The log Kow of the relevant metabolites ranges from -2.6 to 0.4, thereby not fulfilling the screening criteria for bioaccumulation (B/vB) as laid down in Section 3.1 of REACH Annex XIII. In conclusion, all (relevant) predicted metabolites are not expected to significantly accumulate.

#	Metabolite (no)	Smiles	Quantity [mol/mol parent]	Log Kow	BOD prediction (% after 28)
Parent	1	CC1(C)CC(OC(=O)CCCCCCCCC(=O)OC2CC(C)(C)NC(C)(C)C2)CC(C)(C)N1	1E-10	6.5004	0.29
2	2	CC1(C)CC(OC(=O)CCCCCCCCC(O)=O)CC(C)(C)N1	0.00001	1.4396	0.41
3	3	CC1(C)CC(OC(=O)CCCCCCC=CC(O)=O)CC(C)(C)N1	0.00001	2.7246	0.41
4	4	CC1(C)CC(OC(=O)CCCCCCC(O)CC(O)=O)CC(C)(C)N1	1E-005	-0.0987	0.40
5	5	CC1(C)CC(OC(=O)CCCCCCC(=O)CC(O)=O)CC(C)(C)N1	1E-005	-0.6101	0.40
6	6	CC1(C)CC(OC(=O)CCCCCCC(O)=O)CC(C)(C)N1	1E-005	0.4574	0.36
7	7	CC1(C)CC(OC(=O)CCCCC=CC(O)=O)CC(C)(C)N1	1E-005	1.7424	0.36
8	8	CC1(C)CC(OC(=O)CCCCC(O)CC(O)=O)CC(C)(C)N1	9.999E-006	-1.0809	0.35
9	9	CC1(C)CC(OC(=O)CCCCC(=O)CC(O)=O)CC(C)(C)N1	9.999E-006	-1.5923	0.35
10	10	CC1(C)CC(OC(=O)CCCCC(O)=O)CC(C)(C)N1	9.999E-006	-0.5248	0.29
11	11	CC1(C)CC(OC(=O)CCC=CC(O)=O)CC(C)(C)N1	9.999E-006	0.7602	0.29
12	12	CC1(C)CC(OC(=O)CCC(O)CC(O)=O)CC(C)(C)N1	9.999E-006	-2.0631	0.28
13	13	CC1(C)CC(OC(=O)CCC(=O)CC(O)=O)CC(C)(C)N1	9.999E-006	-2.5745	0.28
14	14	CC1(C)CC(OC(=O)CCC(O)=O)CC(C)(C)N1	9.999E-006	-1.5070	0.20
15	15	CC1(C)CC(O)CC(C)(C)N1	0.000412	0.9422	0.01
16	16	CC1(C)CC(=O)CC(C)(C)N1	1.934	0.4308	0.01
17	17	CC1(C)CC(=O)OCC(C)(C)N1	6.593E-007	-0.0188	0.12
18	18	CC(C)(CC(O)=O)NC(C)(C)CO	6.593E-012	-2.8587	0.09
19	19	CC(C)(CC(O)=O)NC(C)(C)C=O	6.593E-007	-2.8834	0.09
20	20	CC(C)(CC(O)=O)NC(C)(C)C(O)=O	0.002181	-2.0410	0.04
21	21	CC(C)NC(C)(C)CC(O)=O	0.0006322	-1.8474	0.05
22	22	CC(C)(CC(O)=O)NC(C)(C)O	0.06312	-2.6451	0.00
23	23	CC(C)(N)CC(O)=O	6.312E-011	-3.2220	0.28
24	24	CC(C)=O	6.312E-011	-0.2350	0.80
25	26	OC(=O)CCC(O)=O	0.01401	-0.7543	0.71
26	27	CC(O)=O	1.367	0.0868	0.73

(metabolites which are predicted at quantity >0.001 after 28 d are highlighted in grey and written in bold letters)

(metabolite no: according to (Q)SAR model CATALOGIC 301C v11.15 – July 2018 (OASIS CATALOGIC v5.13.1.156))