2,6-di-tert-butyl-4-(4,6-bis(octylthio)-1,3,5-triazin-2-ylamino)phenol

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1985-03-13 to 1985-04-10

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Non-GLP study. Guideline from 1981. Deviation to the updated OECD Guideline (adopted 1992): The volume of the test solution was reduced fron 3.0 to 1.5 L.

Qualifier:

according to guideline

Guideline:

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

Deviations:

yes

Remarks:

: volume of test solution reduced to 1.5 L

GLP compliance:

no

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge: Bacteria collected from activated sludge of the sewage treatment plant of CH - 4153 Reinach on 12/03/85
- Preparation of inoculum for exposure: according to guideline

Duration of test (contact time):

28 d

Initial conc.:

10 mg/L

Based on:

test mat.

Initial conc.:

20 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

CO2 evolution

Details on study design:

TEST CONDITIONS
- Solubilising agent: in 300 mL of mineral solution were added 0.5 mL Nonylphenol 10E05P0 (solution of 31.2 mg in 100 ml bidist. water)
- Test temperature: 22 ± 2°C

TEST SYSTEM
- Culturing apparatus: 2 Liter flasks equipped with gas inlet and magnetic stirrer.
- Number of culture flasks/concentration: 1
- Test performed in closed vessels
- Method used to create aerobic conditions: 50 ml/min aeration free of carbon dioxide

SAMPLING
- Sampling frequency: day 5 / 9 / 13 / 16 / 19 / 22 / 27 and 28
- Sampling method: Titration of the carbondioxide, absorbed in the absorbers filled with 0.025 N Barium hydroxide on the days 5 / 9 / 13 / 16 / 19 / 22 / 27 and 28.

Reference substance:

aniline

Parameter:

% degradation (CO2 evolution)

Value:

5

Sampling time:

28 d

Remarks on result:

other: 10 mg test substance/L

Parameter:

% degradation (CO2 evolution)

Value:

7

Sampling time:

28 d

Remarks on result:

other: 20 mg test substance/L

Details on results:

Theoretical carbon dioxide formation:
10 mg test substance/L 37.00 mg CO2/1.5 L
20 mg test substance/L 74.01 mg CO2/1.5 L

Results with reference substance:

The biodegradation was calculated as 20 mg/L 93 % in 28 days.

Interpretation of results:

under test conditions no biodegradation observed

Reference 2

Endpoint:

biodegradation in water: screening tests

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

1985-03-14

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Non GLP. Deivations: The test substance was dissolved in sulfuric acid containing silver sulfate instead of water

Qualifier:

according to guideline

Guideline:

other: DIN 38 409

Deviations:

yes

GLP compliance:

no

Oxygen conditions:

aerobic

Duration of test (contact time):

2 h

Details on study design:

TEST CONDITIONS
- Composition of medium:
Potassium dichromate
Mercury sulfate
Silver sulfate
Sulfuric acid
- Test temperature: 148 +/- 3 °C
- Other:
Titration solution: Ammonia-iron-II-sulfate 0.012 mol/L. The preparation of the stock solution of the reagents was carried out according the method described in the guideline DIN 3O409

TEST SYSTEM
- Culturing apparatus: 250 mL round bottom flasks equiped with a condenser.

Reference substance:

other: Potassium hydrogen phthalate

Parameter:

COD

Value:

2.41 other: g COD/g test item

Results with reference substance:

201 mg COD/L

Description of key information

Not readily biodegradable (according to OECD criteria); poorly biodegradable. 

Additional information

The ready biodegradability of the test item was assessed over a 28 day period by the modified Sturm test (OECD 301B). The nominal test concentrations were 10 and 20 mg a.s./L. The test material attained up to 5 and 7 % biodegradation after 28 days whereas the positive control substance (Aniline) was 93 % degraded after 28 days. These results indicate that the test item cannot be classified readily biodegradable under conditions of the test.

The COD calculted in a study according to DIN 38409 was determined to be 2.41 g COD/ g test item.