Octanethioic acid, S-[3-(triethoxysilyl)propyl] ester, reaction products with 2-methyl-1,3-propanediol and 3-(triethoxysilyl)-1-propanethiol

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:

27 Feb 2007 (Study Plan) - 10 Jul 2007 (Study Report)

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method C.4-D (Determination of the "Ready" Biodegradability - Manometric Respirometry Test)

Version / remarks:

Commission Directive 92/69/EEC, method C.4-D of July 1992:
Manometric Respirometry Test (EEC Publication No. L383 A,
December 1992.

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

adopted July 17, 1992

GLP compliance:

yes (incl. QA statement)

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, adapted

Details on inoculum:

- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): activated sludge (micro organisms form a domestic waste water treatment plant) was supplied by the sewage plant Rossdorf, Germany
- Method of cultivation: The activated sludge was washed by centrifugation and the supernatant liquid phase was decanted. The solid material was re-suspended in tap water and again centrifuged. This procedure was repeated twice.
- Concentration of sludge: 1.5g dry material / L

Reference substance:

other: Sodium benzoate

Parameter:

% degradation (O2 consumption)

Value:

40

Sampling time:

28 d

Details on results:

Points of degradation plot (test substance):

1.5 % degradation after 1 d;
5.5 % degradation after 2 d;
9 % degradation after 3 d;
12.5 % degradation after 4 d;
16 % degradation after 5 d;
21.5 % degradation after 6 d;
28 % degradation after 7 d;
29 % degradation after 8 d;
30 % degradation after 9 d;
30.5 % degradation after 10 d;
32.5 % degradation after 11 d;
33 % degradation after 12 d;
33 % degradation after 13 d;
34.5 % degradation after 14 d;
34.5 % degradation after 15 d;
35 % degradation after 16 d;
35.5 % degradation after 17 d;
36.5 % degradation after 18 d;
36.5 % degradation after 19 d;
37 % degradation after 20 d;
37 % degradation after 21 d;
37.5 % degradation after 22 d;
38 % degradation after 23 d;
39 % degradation after 24 d;
38.5 % degradation after 25 d;
38.5 % degradation after 26 d;
39 % degradation after 27 d;
39.5 % degradation after 28 d.

Results with reference substance:

Points of degradation plot (reference substance):

36 % degradation after 1 d;
49 % degradation after 2 d;
59 % degradation after 3 d;
70 % degradation after 4 d;
76 % degradation after 5 d;
79 % degradation after 6 d;
82 % degradation after 7 d;
83 % degradation after 8 d;
84 % degradation after 9 d;
85 % degradation after 10 d;
86 % degradation after 11 d;
87 % degradation after 12 d;
88 % degradation after 13 d;
89 % degradation after 14 d;
89 % degradation after 15 d;
89 % degradation after 16 d;
89 % degradation after 17 d;
89 % degradation after 18 d;
90 % degradation after 19 d;
91 % degradation after 20 d;
91 % degradation after 21 d;
91 % degradation after 22 d;
92 % degradation after 23 d;
92 % degradation after 24 d;
92 % degradation after 25 d;
91 % degradation after 26 d;
93 % degradation after 27 d;
92 % degradation after 28 d.

Validity criteria fulfilled:

yes

Interpretation of results:

not readily biodegradable

Conclusions:

The percentage biodegradation did not exceed 60% within 10 day window and after 28 days of incubation.

Executive summary:

The test item can be considered as not readily biodegradable.

Description of key information

The test item can be considered as not readily biodegradable.

Key value for chemical safety assessment

Biodegradation in water:

under test conditions no biodegradation observed