REAKTIV-ORANGE DYPR 934

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:

1999-03-24 to 1999-04-21

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Well documented GLP study in compliance with EU method

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1999

Report date:

1999

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

EU Method C.4-E (Determination of the "Ready" Biodegradability - Closed Bottle Test)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Details on test material:

-Name of test material (as cited in study report): Reaktiv-Orange DYPR934

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

other: mixed population of aquatic microrganisms (activated sludge)

Details on inoculum:

Inoculum
source of sewage effluent: secondary effluent of a domestic sewage treatment plant (Kläranlage Odenthal);
Treatment given: separation of coarse particles by filtration
Concentration of effluents in reaction mixture: 5 mL/L (SOP 2030-6600103-99 D)
Preconditioning: aeration 5 days

Duration of test (contact time):

28 d

Initial test substance concentration

Initial test substance concentration 1

Initial conc.:

8 mg/L

Based on:

test mat.

Initial test substance concentration 2

Initial conc.:

2.9 mg/L

Based on:

other: Reference Substance: Sodium bensoate, 99% Purity

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

O2 consumption

Remarks:

During the study period the biodegradation of the test substance is determined on the basis of the reduction of dissolved oxygen.

Details on study design:

TEST CONDITIONS

- Solubilising agent (type and concentration if used): no data
- Test temperature: 20 ± 1°C
- pH adjusted: yes
- other: Improved type for a volatile substance used (no further details given)
CONTROL AND BLANK SYSTEM
- Inoculum blank: yes
- Toxicity control: yes (Sodium benzoate)

TEST SYSTEM

- Measuring equipment: According to SOP 2030-0000104-98 D
- Test performed in closed vessels

INOCULUM:
Source of sewage effluent: secondary effluent of a domestic sewage treatment plant (Kläranlage Odenthal)
Treatment given: Separation of coarse particles by filtration
Concentration of effluents in reaction mixture: 5 mL/L
-Preconditioning: aeration for 5 days.
Study condition:
Duration: 28 days


SAMPLING (- Sampling frequency - Sampling method- Sample storage before analysis : according to the guideline) as well as SOP 2030-6600401-96 D

REFERENCE SUBSTANCE: sodium benzoate
PURITY: 99%
Initial concentration: 2.9 mg/L reference substance

Reference substance

Reference substance:

other: Natriumbenzoat

Results and discussion

Test performance:

Test substance is suspended in a mineral medium, inoculated with a mixed population of aquatic microorganisms and incubated for 28 days under aerobic conditions in the dark at 20 ± 1°C

% Degradation

Value:

0

Sampling time:

28 d

Details on results:

Points of degradation plot (test substance): 1 % degradation after 7 d 0 % degradation after 14 d 1 % degradation after 21 d 0 % degradation after 28 d
The test results indicate no hazard potential.

BOD5 / COD results

Results with reference substance:

Points of degradation plot (reference substance): 70 % degradation after 7 d 78 % degradation after 14 d 85 % degradation after 21 d 84 % degradation after 28 d
see more details below.

Any other information on results incl. tables

Results-DO depletion: % Degradation

 

Test substance Test concentration: 8.4 mg/L ThoD: 839 mg/g COD---mg/g	DO depletion after n days                                 [mg/L]
No.1: (mt0-mtx)-(mb0-mbx)	7 d 0.04	0.00	0.07	0.00
No.2: (mt0-mtx)-(mb0-mbx)	0.00	0.00	0.07	0.00
D1: % Degradation	1	0	1	0
D2: % Degradation	0	0	1	0
D, Mean	0	0	1	0

 

Reference substance Test concentration: 2.9 mg/L ThoD: 1665 mg/g COD---mg/g	DO depletion after n days                                              [mg/L]
No.1: (mt0-mtx)-(mb0-mbx)	7d 3.35	14d 3.74	21d 4.08	28d 4.03
No.2: (mt0-mtx)-(mb0-mbx)	3.40	3.76	4,13	4.06
D1: % Degradation	69	77	84	83
D2: % Degradation	70	78	86	84
D, Mean	70	78	85	84

 

*Toxicity control	DO depletion after n days                                              [mg/L]
No.1: (mt0-mtx)-(mb0-mbx)	7d 3.29	14d 3.70	21d 4.08	28d 4.03
No.2: (mt0-mtx)-(mb0-mbx)	3.34	3.82	4.13	4.10
D1: % Degradation	28	31	34	34
D2: % Degradation	28	32	35	35
D, Mean	28	32	35	35

 

*In the toxicity control 8.4 mg/L test substance and 2.9 mg/L reference substance were used. The ThOD values respectively COD values of these substances are shown in the table above.

 

Dissolved oxygen(mg O2/l, mean values)

No. of days	Blank inoculum (bottles 1-10)	Refernce substance (bottles 11-20)	Test substance (bottles 41-50)	Toxicity Control (bottles 51-60)
0	9.42	9.41	9.36	9.35
7	9.15	5.76	9.08	5.76
14	8.96	5.2	8.94	5.13
21	8.98	4.86	8.85	4.8
28	8.71	4.65	8.8	4.57

 

Oxygen depletionafter 28 d (mg/l, mean values):

Inoculum blank	No data
Test substance	0
Reference substance	84
Toxicity control	35

Result: Within the test period of 28 days, a degradation of 0 % was determinded for Reaktiv-Orange DYPR 934. Reaktiv-Orange DYPR 934 has to be classified as “Not Readily Biodegradable”

Biodegradability:

0 % (28 d)

Method: Modified OECD Screening Test

The test results indicate no hazard potential.

The test substance is not readily biodegradable; so longer resident times of the substance in surface water are to be expected. However on the basis of the ecotoxicological test results there is no hazard potential.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

under test conditions no biodegradation observed

Conclusions:

The test results indicate no hazard potential.
The test substance is not readily biodegradable.

Executive summary:

Result: Within the test period of 28 days, a degradation of 0 % was determinded for Reaktiv-Orange DYPR 934. Reaktiv-Orange DYPR 934 has to be classified as “Not Readily Biodegradable”

Biodegradability = 0 %

The test results indicate no hazard potential.