A mixture of: sodium/potassium 7-[[[3-[[4-((2-hydroxy-naphthyl)azo)phenyl]azo]phenyl]sulfonyl]amino]-naphthalene-1,3-disulfonate

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

biodegradation in water: ready biodegradability

Remarks:

AFNOR - Test

Type of information:

experimental study

Adequacy of study:

key study

Study period:

14 August 1992- 16 December 1992

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 A (old version) (Ready Biodegradability: Modified AFNOR Test)

Deviations:

yes

Remarks:

Determination of bacteria concentration: by plating - Inoculum: effluent of a domestic sewage treatment plant

Qualifier:

according to guideline

Guideline:

other: EEC Directive, Annex V, C.4

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Code number: FAT45155/B
Batch number: TV1
Appearance: solid
Solubility: ~100g/l (in water) [estimation]
Storage: room temperature + light protected
Expiration date: 15.5.1997

Oxygen conditions:

aerobic

Inoculum or test system:

sewage, domestic, non-adapted

Details on inoculum:

strain: mixture of polyvalent bacteria effluent of a domestic sewage treatment plant collecting date: 27.08.1992
bacteria concentration: 1.5 x 10E7

Duration of test (contact time):

28 d

Initial conc.:

40 mg/L

Based on:

DOC

Parameter followed for biodegradation estimation:

DOC removal

Details on study design:

Test temperature: 25 ±1 °C
Lighting: indirect daylight

Reference substance:

other: Glucose

Preliminary study:

no data

Parameter:

% degradation (DOC removal)

Value:

0

Sampling time:

28 d

Details on results:

degradation (%) for test material:
day 3: 0
day 7: 0
day 14: 0
day 28: 0

Results with reference substance:

Degradation after 14 and 28 days was 100 %.

Validity criteria fulfilled:

yes

Interpretation of results:

not readily biodegradable

Conclusions:

FAT 45155 is not readily biodegradable.

Executive summary:

In a GLP compliant study, the ready biodegradability of FAT - 45155/B was determined in a 28-days AFNOR - Test according to the OECD Guideline 301A and EU method C.4. The test substance and the reference substance were tested in a concentration of 40 mg/l DOC nominal. The biodegradation (28 days) of FAT 45155/B is 0 % while that of the reference substance is 100 %. Based on the results, FAT 45155/B is not readily biodegradable. 

Reference 2

Endpoint:

biodegradation in water: inherent biodegradability

Remarks:

Zahn-Wellens - Test

Type of information:

experimental study

Adequacy of study:

key study

Study period:

10 July 1992 to 14 October 1992

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 302 B (Inherent biodegradability: Zahn-Wellens/EMPA Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: EEC Directive, L133 (pp. 99-105), Volume 31, May 88

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Code number: FAT45155/B
Batch number: TV1
Appearance: solid
Solubility: ~100g/l (in water) [estimation]
Storage: room temperature + light protected
Expiration date: 15.5.1997

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, industrial, non-adapted

Details on inoculum:

strain: sludge of a biological sewage treatment plant (ARA-Basel Industrie) collecting date: 21.07.1992

Duration of test (contact time):

28 d

Initial conc.:

150 mg/L

Based on:

DOC

Initial conc.:

440 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

DOC removal

Details on study design:

Water / Nutrient: according to the specification of the EEC Directive, L133 (pp. 99-105), Volume 31 resp. OECD Method 302B
Test temperature: 22 ± 3 °C
Lighting: indirect daylight

Reference substance:

diethylene glycol

Preliminary study:

no data

Test performance:

sludge concentration: 1040 mg/L

Parameter:

% degradation (DOC removal)

Value:

12.2

Sampling time:

28 d

Details on results:

degradation (%) of test substance:
0 h: 9.7
3 h: 9.2
2 d: 10.8
7 d: 12.2
14 d: 17.2
21 d: 19.5
28 d: 12.2

Results with reference substance:

degradation on day 13: 100 %

Calculation

The bioelimination at the time t is calculated from the DOC values of the preliminary test an the main test accoding to:

 

Biodegradation

 

D_t(%)= [1 – DOC_t- DOC_{bI x t}/ DOC_pr ] x 100

 

where:

D_t= biodegradation (%) at time t

DOC_pr = value of the test substance preliminary test (mg/l DOC)

DOC_t= value of the test substance at day t (mg/l DOC)

DOC_{bl x t}= blank control at time t

Validity criteria fulfilled:

yes

Interpretation of results:

not inherently biodegradable

Conclusions:

The degradation of FAT 45155/B after 28 days was 12.2 % and is considered as not inherently biodegradable in the "modified Zahn-Wellens Test".

Executive summary:

In a GLP-compliant study, the inherent biodegradability of FAT - 45155/B was determined in a 28-days Zahn-Wellens-Test according to the OECD Guideline 302B. The test substance was tested in concentration of 150 mg/l DOC. The reference substance Diethylenglycol was also tested in a concentration of 150 mg/l DOC. The bioelimination (28d) of FAT - 45155/B is 12.2 % while that of reference substance is 100 %. Based on the study results, test substance is considered as not inherently biodegradable.

Description of key information

The test substance is neither inherently nor readily biodegradable.

Key value for chemical safety assessment

Biodegradation in water:

not biodegradable

Type of water:

freshwater

Additional information

The ready biodegradability test of test substance was conducted according to modified AFNOR-TEST - OECD 301A. The biodegradation of test substance was 0 % on day 28 and the degradation of reference substance glucose was 100 % after 14 days, which indicates that the test substance is not readily biodegradable. The BOD5 was 8 mg O2/g under valid test conditions. The COD of test substance was 998 mg O2/g. The BOD5/COD ratio is 0.8 %. Test substance was investigated for its biodegradability in the "28-Day modified Zahn-Wellen Test" according to OECD guideline method 302B. The degradation of test substance after 28 days was 12.2 % whereas the degradation of reference substance on day 28 was 100 %. Consequently, test substance is not inherent biodegradable over the 28-day test period under valid test conditions. In conclusion, the test substance is non-biodegradable.