Manganese, [[2,2',2''-[nitrilotris[2,1-ethanediyl(nitrilo-.kappa.N)methylidyne]]tris[phenolato-.kappa.O]](3-)]-, (OC-6-22)-

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:

2002-09-27 to 2002-11-28

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: OECD guideline study, GLP.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2002

Report date:

2002

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test)

Version / remarks:

adopted 1993

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.4-D (Determination of the "Ready" Biodegradability - Manometric Respirometry Test)

Version / remarks:

adopted 1992

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

479-540-8

EC Name:

-

Cas Number:

61007-89-4

Molecular formula:

C27 H27 Mn N4 O3

IUPAC Name:

manganese(3+) 2-[({2-[bis(2-{[(2-oxidophenyl)methylidene]amino}ethyl)amino]ethyl}imino)methyl]benzen-1-olate

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge: Mixture of polyvalent bacteria (activated sludge) from the aeration tank of a domestic sewage treatment plant, ARA Pro Rheno Basel communal.
- Pretreatment: The activated sludge was washed 4 times with tap water and the last time with test medium. A sample of the activated sludge was taken to determine the dry weight of the Suspended Solids. An amount corresponding to 2 - 3 g per litre of suspended solids was mixed with test medium. The pre-treated sludge was aerated until use
- Concentration of sludge: 30 mg/L

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

100 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

TEST CONDITIONS
- Composition of medium: The test water was prepared according to the testing guidelines.
- Test temperature: 21°C
- pH: pH value of all incubation flasks was measured at the beginning and at the end of the test
- pH adjusted: no
- Continuous darkness: yes

TEST SYSTEM
- Test vessels: 500 mL conical vessels containing 250 mL test medium, continuously stirred
- Test apparatus: Voith Sapromat apparatus
- Number of culture flasks/concentration:
Test item: 2 vessels
Inoculum control: 2 vessels
Procedure control: 2 vessels
Abiotic sterile control: 1 vessel
Inhibition control: 1 vessel

Biochemical Oxygen Demand: measured continuously by means of a BOD-meter
Biodegradation: Calculated on the basis of the ThOD
Oxygen consumption: automatically measured by the test apparatus (Voith Sapromat)


STATISTICAL METHODS: not performed

Reference substance

Reference substance:

other: Sodium benzoate

Results and discussion

% Degradation

Parameter:

% degradation (O2 consumption)

Value:

55

Sampling time:

28 d

Details on results:

Points of degradation plot (test substance):
14 % degradation after 2 d
38 % degradation after 5 d
51 % degradation after 16 d
54 % degradation after 22 d
55 % degradation after 26 d
55 % degradation after 28 d

BOD5 / COD results

Results with reference substance:

Points of degradation plot (reference substance):
38 % degradation after 2 d
59 % degradation after 5 d
83 % degradation after 16 d
86 % degradation after 22 d
87 % degradation after 26 d
87 % degradation after 28 d

Any other information on results incl. tables

The biodegradation of the test substance was determined as 55% after 28 days of incubation. The test item did not reach the pass level of 60% for ready biodegradability in the Manometric Respirometry Test neither within the 10-day window nor after 28 days of incubation. Therefore, the test substance cannot be assessed as readily biodegradable.