Reaction mass of Octyl-3-[3-tert-butyl-4-hydroxy-5-(5-chloro-2H-benzotriazole-2-yl)phenyl]propionate and 2-Ethylhexyl-3-[3-tert-butyl-4-hydroxy-5-(5-chloro-2H-benzotriazole-2-yl)phenyl]propionate

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:

From January 2, 1989 to February 21, 1989

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge (adaptation not specified)

Details on inoculum:

- Source of inoculum/activated sludge: Bacteria collected from activated sludge of the sewage treatment plant of CH-4153 Reinach.

Duration of test (contact time):

28 d

Initial conc.:

10.2 mg/L

Based on:

test mat.

Initial conc.:

20 mg/L

Based on:

test mat.

Reference substance:

aniline

Parameter:

% degradation (CO2 evolution)

Remarks:

for 10.2 mg test substance/l

Value:

7

Sampling time:

28 d

Parameter:

% degradation (CO2 evolution)

Remarks:

for 20 mg test substance/l

Value:

2

Sampling time:

28 d

Results with reference substance:

At Day 28 during the study, the biodegradation was 84.3 %.

Table 1. The biodegradation of reference substance

Day			Ref.: Aniline 20 mg/l
	CO2 evol.		CO2 evol.		Biodegrad.
	Blank+Vehicle		Reference		Reference
	[mg]	[mg]*	[mg]	[mg]*	[%]	[%]*
6	4.7	4.7	39.2	39.2	46.1	46.1
10	0.8	5.5	15.0	54.2	17.6	63.8
13	0.5	6.0	4.0	58.3	4.7	68.5
17	0.6	6.6	4.0	62.2	4.7	73.1
20	0.6	7.2	3.7	65.9	4.4	77.5
21	0	7.2	0.1	66.1	0.2	77.7
24	0.5	7.7	2.4	68.5	2.8	80.5
27	0.4	8.1	2.5	71.0	3.0	83.5
28	0.8	8.9	0.7	71.7	0.9	84.3

* = cumulative values

For calculation of the degradation the degradation the Blank+Vehicle is used.

Table 2. The biodegradation of test substance: TK 12871

Day	Concentration 10 mg/l				Concentration 20 mg/l
	CO2 evolution		Biodegrad.		CO2 evolution		Biodegrad.
	[mg]	[mg]*	[%]	[%]*	[mg]	[mg]*	[%]	[%]*
6	0.6	0.6	1.5	2	0.4	0.4	0.6	1
10	-0.2	0.4	-0.6	1	0.2	0.7	0.3	1
13	0.4	0.8	1.1	2	0.3	1.0	0.4	1
17	0.4	1.2	0.9	3	0.2	1.2	0.3	2
21	1.4	1.4	3.6	4	1.5	1.5	1.9	2
24	0	1.4	0.1	4	0	1.5	0	2
27	0.3	1.7	0.7	4	0.3	1.8	0.3	2
28	1.0	2.6	2.4	7	0.1	1.9	0.2	2

* = cumulative values

The negative degradation values are within the variation of the method.

Validity criteria fulfilled:

not specified

Interpretation of results:

not readily biodegradable

Conclusions:

According to OECD 301B test method, TK 12871 (TINUVIN 109) was not biodegradable.

Executive summary:

This test using the procedures outlined in the CIBA-GEIGY Ltd Study Plan for 884482 and OECD 301B (OECD, 1981). TK 12871 (TINUVIN 109) was not be considered readily biodegradable under the test conditions and the percentage biodegradation of TK 12871 (TINUVIN 109) in sludge was less than 60 %.

Description of key information

Not readily biodegradable (OECD TG 301B).

Key value for chemical safety assessment

Biodegradation in water:

under test conditions no biodegradation observed

Additional information

At Day 28 during the study, the biodegradation of the reference substance was 84.3 %. TK 12871 (TINUVIN 109) was not be considered readily biodegradable under the test conditions and the percentage biodegradation of TK 12871 (TINUVIN 109) in sludge was less than 60 %.