PIGMENT ROT 5021 A

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:

1992-01-10 to 1992-02-11

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP compliant; Guideline Study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1992

Report date:

1992

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.4-C (Determination of the "Ready" Biodegradability - Carbon Dioxide Evolution Test)

Version / remarks:

reported as 84/449/EEC C.5 Biotic degradation: modified Sturm test

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

Bacteria collected from activated sludge of the sewage treatment plant of CH-4153 Reinach on 13/01/92. The pH after collection was 7.7 .
The preparation was carried out according to the method described in the guideline.

Duration of test (contact time):

28 d

Initial test substance concentration

Initial test substance concentration 1

Initial conc.:

20.9 mg/L

Based on:

test mat.

Initial test substance concentration 2

Initial conc.:

40.2 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

CO2 evolution

Details on study design:

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

Reference substance

Reference substance:

aniline

Results and discussion

Test performance:

1200 mL water with the inoculum were aerated for 24 hours in the test vessel. In 300 mL water 15 mL Polyoxyethylen-Sorbitan-Monooleate (TWEEN 80 FLUKA 93781) (solution of 30 mg in 100 mL bidist. water) and 31.4 rsp. 60.3 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 3.0 mg/L TWEEN 80

% Degradation

% Degradation 1

Parameter:

% degradation (CO2 evolution)

Value:

7

Sampling time:

28 d

Remarks on result:

other: 20.9 mg test substance/L

% Degradation 2

Parameter:

% degradation (CO2 evolution)

Value:

2

Sampling time:

28 d

Remarks on result:

other: 40.2 mg test substance/L

BOD5 / COD results

Results with reference substance:

Biodegradation of the reference substance: 93% in 28 days

Any other information on results incl. tables

The biodegradation was calculated as:

20.9 mg test substance/L = 7% in 28 days.

40.2 mg test substance/L = 2% in 28 days.

Reference substance: 20 mg/L = 93% in 28 days.