Registration Dossier

Environmental fate & pathways

Biodegradation in water: screening tests

Currently viewing:

Administrative data

Link to relevant study record(s)

Referenceopen allclose all

Endpoint:
biodegradation in water: ready biodegradability
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Comparative testing and validation programme based on scientific principles and comparable to (later) established guidelines.
Qualifier:
according to
Guideline:
OECD Guideline 301 D (Ready Biodegradability: Closed Bottle Test)
GLP compliance:
no
Oxygen conditions:
aerobic
Inoculum or test system:
other: sewage treatment plant effluent
Details on inoculum:
In the ring test effluents of different industral waste water treatment plants was used:
Bayer AG: Bürrig sewage treatment plant effluent,
Hüls AG: CWH activated sludge test plant effluent,
BASF AG: industrial sewage treatment plant effluent,
Merck: Industrial sewage treatment plant effluent,
Henkel & Cie GmbH: Hochdahl sewage treatment plant effluent,
Solvay: effluent (source not reported).
Duration of test (contact time):
30 d
Initial conc.:
2
Based on:
test mat.
Parameter followed for biodegradation estimation:
O2 consumption
Parameter:
other: BOD5
Remarks:
% BOD
Value:
ca. 44.9
Sampling time:
5 d
Remarks on result:
other: average of the three results depicted below
Parameter:
BOD5
Value:
39.5 other: % BOD (5 d)
Remarks on result:
other: result a
Parameter:
BOD5
Value:
42.1 other: % BOD (5 d)
Remarks on result:
other: result b
Parameter:
BOD5
Value:
53.2 other: % BOD (5 d)
Remarks on result:
other: result c

- Kinetic of degradation (mean values in % BOD)
Time [d] BASF AG Bayer Huels Henkel Merck Solvay
a b c
5 39.5 42.1 53.2   0 0.7 16.2 25
15 85.1 101 116 85.4 2.1 0 86.9 68.0
30 85.1 122 98.8 94.9 4.7 0 95.4 85.0
Validity criteria fulfilled:
yes
Interpretation of results:
readily biodegradable
Conclusions:
Rapid biodegradation was observed.
Executive summary:

In a ring test effluents of different industral waste water treatment plants was used to investigate biodegradability of the test substance according to OECD guideline 301 -D (Closed-Bottle Test): Bayer AG: Bürrig sewage treatment plant effluent, Hüls AG: CWH activated sludge test plant effluent, BASF AG: industrial sewage treatment plant effluent, Merck: Industrial sewage treatment plant effluent, Henkel & Cie GmbH: Hochdahl sewage treatment plant effluent, Solvay: effluent (source not reported).

The test substance showed rapid biodegradation.

Endpoint:
biodegradation in water: inherent biodegradability
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: comparable to guideline study with acceptable restrictions
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 302 B (Inherent biodegradability: Zahn-Wellens/EMPA Test)
GLP compliance:
no
Oxygen conditions:
aerobic
Inoculum or test system:
activated sludge, industrial (adaptation not specified)
Duration of test (contact time):
9 d
Initial conc.:
1 298 mg/L
Based on:
other: TOC
Parameter followed for biodegradation estimation:
DOC removal
Details on study design:
preparation of the test assay:
- inoculum: 1 g/L dry weight
- incubation: at room temperature (20-25 °C) on a magnetic stirrer, aerated with air (sparging)
Reference substance:
not specified
Parameter:
% degradation (DOC removal)
Value:
ca. 98
Sampling time:
9 d
Details on results:
Kinetic of test substance (in %):
< 0 after 3 hour(s)
ca. 82 after 5 day(s)
ca. 85 after 7 day(s)

TOC disapearance

Time

3 h

1 d

5 d

7 d

9 d

Replicate 1

 

 

 

 

 

TOC measured [mg/L]

428

403

66

65

42

Theoretical TOC [mg/L]

400

393

387

386

386

Blank [mg/L]

12

18

25

19

32

TOC - Blank [mg/L]

416

385

41

46

10

TOC elimination [%]

0

2

89

88

97

Replicate 2

 

 

 

 

 

TOC measured [mg/L]

422

333

63

61

37

Theoretical TOC [mg/L]

400

395

390

389

389

Blank [mg/L]

12

18

25

19

32

TOC - Blank [mg/L]

410

375

38

42

5

TOC elimination [%]

0

5

90

89

99

Comment on the calculation of the elimination (%): samples were taken at regular intervals and the sample volume was always replaced with tap water. Thus, the starting liquid volume remained constant whereas the TOC-reference point was reduced according to the sample volume.

Validity criteria fulfilled:
yes
Interpretation of results:
other: easily eliminated from water
Conclusions:
The test substance was easily eliminated from water.
Executive summary:

An inherent biodegradation test was performed in accordance with OECD guideline 302 -B (Zahn-Wellens Test). Test was completed after exposure time of 9 days, since a complete degradation (98% DOC removal) was achieved in this time period.

Endpoint:
biodegradation in water: ready biodegradability
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
Remarks:
Guideline study, basic data given but no detailed test protocol available as the tests from the Japanese authorities are only published as short result summary including deviations (if oocured). Nevertheless, test details are given by MITI guideline and an overall test description of CITI Japan.
Qualifier:
according to
Guideline:
OECD Guideline 301 C (Ready Biodegradability: Modified MITI Test (I))
GLP compliance:
not specified
Oxygen conditions:
aerobic
Inoculum or test system:
activated sludge (adaptation not specified)
Details on inoculum:
- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): Sludge was taken from 10 different sites in Japan (municipal STPs, industrial STPs, lakes, rivers and bays)
- Concentration of sludge: 30 mg/l dry substance
Duration of test (contact time):
28 d
Initial conc.:
100
Based on:
test mat.
Parameter followed for biodegradation estimation:
O2 consumption
Details on study design:
TEST CONDITIONS
- Solubilising agent (type and concentration if used): no data
- Test temperature: 25 °C +/- 1°C
- pH: 7.0
- 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 (Aniline)

TEST SYSTEM
- Measuring equipment: Closed system oxygen consumption measuring apparatus (Coulometer: Ohkura Electric Co Ltd.)
- Details of trap for CO2 and volatile organics if used: Soda lime No.1 (extra pure reagent, Wako Pure Chemicals Ind. Ltd.)
Reference substance:
not specified
Parameter:
% degradation (O2 consumption)
Value:
73
Sampling time:
28 d
Details on results:
RS-Freetext:
- Based on BOD measurements:
% BOD/ThBOD (28 d): #1: 73, #2: 73, #3: 73, mean: 73

- Based on TOC measurements:
% TOC removal (28 d): #1: 96, #2: 95, #3: 98, mean: 96

- Based on GC measurements:
% NMP removal (28 d): #1: 100, #2: 100, #3: 100, mean: 100
Validity criteria fulfilled:
yes
Interpretation of results:
readily biodegradable
Conclusions:
Test substance can be classified as ready biodegradable
Executive summary:

A biodegradation test according to OECD guideline 301 -C (MITI test) was performed. test period was 28 days, sludge of 10 different japanese municipal sewage treatment plants was used as inoculum. Based on the observed results, the test substance can be classified as ready biodegradable

Endpoint:
biodegradation in water: inherent biodegradability
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Comparable to guideline study with acceptable restrictions (eg. inoculum: industrial activated sludge instead of sludge of a wwtp treating domestic sewage)
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 302 B (Inherent biodegradability: Zahn-Wellens/EMPA Test)
GLP compliance:
no
Oxygen conditions:
aerobic
Inoculum or test system:
activated sludge, industrial (adaptation not specified)
Duration of test (contact time):
13 d
Initial conc.:
400 mg/L
Based on:
DOC
Parameter:
% degradation (DOC removal)
Value:
98
Sampling time:
13 d
Details on results:
- Kinetic of elimination:

Time DOC Blank Test substance [mg/L DOC] DOC elimination [%]
[d] [mg/L] #1 #2 #1 #2 mean
0 400
3 hours 395 21 405 402 3 4 4
1 390 21 387 402 6 2 4
2 386 18 344 357 16 12 14
5 386 40 60 62 95 94 95
7 386 30 51 50 95 95 95
9 386 31 51 43 95 97 96
13 386 27 34 34 98 98 98

- The sigmoidal shape of the elimination curve is a strong indication of biodegradation
-        Comment on the calculation of the elimination (%) after 3 h, on day 1 and day 2: samples were taken and the sample volume (approx. 50 ml) was replaced with tap water. Thus, the starting volume remained constant (approx. 2000 ml), but the reference value to calculate the elimination degree had to be corrected after each sampling
Validity criteria fulfilled:
yes
Interpretation of results:
other: easily eliminated from water (mainly by biodegradation)

Description of key information

Test substance is readily biodegradable according to OECD criteria.

Key value for chemical safety assessment

Biodegradation in water:
readily biodegradable

Additional information

Ready biodegradability of the test substance was demonstrated by CITI (1992) in a MITI-test according to OECD guideline 301 -C. Test period was 28 days, sludge of 10 different japanese municipal sewage treatment plants was used as inoculum. Based on the observed results, the test substance can be classified as ready biodegradable

An inherent biodegradation test was also performed in accordance with OECD guideline 302-B (Zahn-Wellens Test). Test was completed after exposure time of 9 days, since a complete degradation (98% DOC removal) was achieved in this time period.

These results are confirmed by several further available study reports.