2-(2H-benzotriazol-2-yl)-4,6-ditertpentylphenol

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:

1988-09-22 to 1988-11-01

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Non-GLP guideline study. Deviatioins to the updated guideline (adopted 1992): no abiotic sterile and toxicity control, sampling days reduced, reduced test solution

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1988

Report date:

1988

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Deviations:

yes

Remarks:

, volume of test solution was reduced from 3 to 1.5 liter. The CO2 formed was absorbed with NaOH. An emulsifier was used. CO2 production of the blank was 29.3 mg/l medium

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

2-(2H-benzotriazol-2-yl)-4,6-ditertpentylphenol

EC Number:

247-384-8

EC Name:

2-(2H-benzotriazol-2-yl)-4,6-ditertpentylphenol

Cas Number:

25973-55-1

Molecular formula:

C22H29N3O

IUPAC Name:

2-(2H-benzotriazol-2-yl)-4,6-bis(1,1-dimethylpropyl)phenol

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): sewage treatment plant of CH-4153 Reinach on 1988-09-20

Duration of test (contact time):

28 d

Initial test substance concentration

Initial test substance concentration 1

Initial conc.:

10 mg/L

Based on:

test mat.

Initial test substance concentration 2

Initial conc.:

20 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

CO2 evolution

Details on study design:

TEST CONDITIONS
1200 mL of the mineral solution with the inoculum were aerated for 24 hours in the test vessel. In 300 mL mineral solution 0.5 ml Nonylphenol 10E05P0 (solution of 31.2 mg in 100 mL bidist. water) and 15 rsp. 30 mg of test substance were added and homogenized. This solution was given to the test vessel which was immediately connected to the CO2 traps.
- Solubilising agent (type and concentration if used): Nonylphenol 10E05P0
- Test temperature: 22 ± 2°C
- Aeration of dilution water: 25 ml/min free of carbon dioxide

TEST SYSTEM
- Culturing apparatus: 2 liter flasks equipped with gas inlet and magnetic stirrer
- Number of culture flasks/concentration: 1
- Method used to create aerobic conditions: magnetic stirrer
- Details of trap for CO2 and volatile organics if used: The CO2 formed by biodegradation was absorbed with NaOH and determined on a carbon analyzer

SAMPLING
- Sampling frequency: On the days 5, 11, 18, 22, 27 and 28
- Sampling method: Determination on a carbon analyzer of the initial CO2 of the 0.05 N sodium hydroxide and the CO2, absorbed in the absorbers filled with 200 ml 0.05 N sodium hydroxide

CONTROL AND BLANK SYSTEM
- Inoculum blank: water as specified in the guideline
- Abiotic sterile control: no
- Toxicity control: no
- Vehicle control: water as specified in the guideline containing 0.5 ml of the Nonylphenol solution

Reference substance

Reference substance:

aniline

Results and discussion

% Degradation

% Degradation 1

Parameter:

% degradation (CO2 evolution)

Value:

8

Sampling time:

28 d

Remarks on result:

other: in 10 mg/L test substance

% Degradation 2

Parameter:

% degradation (CO2 evolution)

Value:

2

Sampling time:

28 d

Remarks on result:

other: in 20 mg/L test substance

BOD5 / COD results

Results with reference substance:

94.4% biodegradation in 28 days at 20 mg aniline/L