Disodium 2,2'-(9,10-dioxoanthracene-1,4-diyldiimino)bis(5-methylsulphonate)

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

biodegradation in water: ready biodegradability

Remarks:

prediction

Type of information:

(Q)SAR

Adequacy of study:

supporting study

Study period:

2023

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Justification for type of information:

QSAR estimation

Qualifier:

no guideline required

Principles of method if other than guideline:

QSAR dyes R&C report produced by version QSAR dyes RC 2.0 Developed by Milano Chemometrics and QASR research group Dept. Earth and Environmental Science, University Milano Bicocca, Italy.

GLP compliance:

no

Parameter:

probability of ready biodegradability (QSAR/QSPR)

Remarks on result:

not readily biodegradable based on QSAR/QSPR prediction

Validity criteria fulfilled:

not applicable

Remarks:

estimation by prediction tool

Interpretation of results:

not readily biodegradable

Conclusions:

QSAR Prediction - the substance resulted as not readily biodegradable.

Executive summary:

The substance resulted not readily biodegradable based on similarities, physical-chemical properties and dyes chemistry.

Reference 2

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

other: Expert Judgement

Adequacy of study:

key study

Study period:

2023

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

no guideline required

Principles of method if other than guideline:

Expert Judgement

GLP compliance:

no

Inoculum or test system:

other: not applicable

Parameter followed for biodegradation estimation:

other: Expert Judgement

Parameter:

other: Ready Biodegradability based on Expert Judgement

Remarks on result:

other: not readily biodegradable based on expert judgement

Validity criteria fulfilled:

not applicable

Interpretation of results:

not readily biodegradable

Conclusions:

not readily biodegradable based on an expert judgement.

Executive summary:

Not readily biodegradable based on an expert judgement.

Reference 3

Endpoint:

biodegradation in water: screening tests

Type of information:

other: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

supporting study

Study period:

April 02, 1974

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

abstract

Qualifier:

no guideline followed

Principles of method if other than guideline:

Internal Method DEV 4 and DEV 5.
No more data available

GLP compliance:

no

Oxygen conditions:

aerobic

Inoculum or test system:

not specified

Duration of test (contact time):

ca. 5 d

Initial conc.:

ca. 42 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Parameter:

BOD5

Value:

ca. 39 mg O2/g test mat.

Parameter:

COD

Value:

ca. 1 180 mg O2/g test mat.

Parameter:

BOD5*100/COD

Value:

3

Validity criteria fulfilled:

not applicable

Interpretation of results:

not readily biodegradable

Conclusions:

The test substance was tested for the determination of the BOD5/COD ratio following the internal methods Nr. 16 and Nr. 15. Under the experimental conditions reported the BOD5/COD ratio is 0.03. The test substance is not readily biodegradable.

Executive summary:

Method:

Internal method Nr. 16 and Nr.15

Results:

BOD5= 39 mg O2/g

COD= 1180 mg O2/g

BOD5/COD= 0.03

Conclusion:

Not readily biodegradable.

Reference 4

Endpoint:

biodegradation in water: inherent biodegradability

Type of information:

other: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

supporting study

Study period:

From April 16 to May 14, 1991

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Remarks:

The test was conducted by means of a read-across approach. The reliability of the source study report is 1.

Qualifier:

according to guideline

Guideline:

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

Deviations:

not specified

GLP compliance:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge (adaptation not specified)

Details on inoculum:

- Source of inoculum/activated sludge: the aeration stage of the Severn Trent PLC Sewage Treatment Plant at Belper, Derbyshire, treating predominantly domestic sewage.
- Pretreatment: the sample was maintained at 21°C with continuous aeration and washed by settlement and resuspension in test medium prior to use.
- Concentration of sludge: equivalent to 1.0 g dry weight/L.

Duration of test (contact time):

ca. 28 d

Initial conc.:

ca. 100 mg/L

Based on:

act. ingr.

Parameter followed for biodegradation estimation:

DOC removal

Details on study design:

Temperature: 22°C ± 1°C
Lighting: the test was conducted in darkness
Evaporation: losses by evaporation were made good by the addition of deionised water immediately prior to sampling.
Sampling: Aeration of the test vessels was stopped and the contents of the vessels allowed to Bettle for 20 minutes. Samples (appoximately 20 ml) were withdrawn from the supernatent and centrifuged at 3900 rpm for 15 minutes to remove any further suspended solids. Samples were analysed immediately. Samples were taken at 0 and 3 hours and an Days 7, 14, 21, 27 and 28 for dissolved organic carbon and spectrophotometric analysis.

Reference substance:

diethylene glycol

Parameter:

% degradation (DOC removal)

Value:

> 4 - < 6

Sampling time:

28 d

Results with reference substance:

Digol attained 100 % degradation within 14 days.

pH values did not drop below 5.2 in any culture vessel during the course of the study and were readjusted to between pH 7 and 8 daily. Dissolved oxygen levels remained at approximately 7.4 mg O₂/L or above in all culture vessels at all times.

Validity criteria fulfilled:

yes

Interpretation of results:

not inherently biodegradable

Conclusions:

The inherent biodegradability of the test substance was determined in a 28 days Zahn-Wellens test, according to the OECD TG 302B. Under the experimental conditions reported the bioelimination of the test substance measured as DOC removal after 28 days is between 4% and 16%.

Executive summary:

Methods:

The inherent biodegradability of the test substance was determined in a 28 days Zahn-Wellens -test according to the OECD Guideline for Testing of Chemicals, No. 302B.

Results:

Bioelimination of test substance measured as DOC removal after 28 days is between 4% and 16%.

Description of key information

The inherent biodegradability of the test substance was determined in a 28 days Zahn-Wellens test, according to the OECD TG 302B. Under the experimental conditions reported the bioelimination of the test substance measured as DOC removal after 28 days is between 4% and 16%.

 

The test substance was tested for the determination of the BOD5/COD ratio following the internal methods Nr. 16 and Nr. 15. Under the experimental conditions reported the BOD5/COD ratio is 0.03. The test substance is not readily biodegradable.

 

Based on a QSAR prediction, the substance resulted as not readily biodegradable.

 

The substance is not readily biodegradable based on an expert judgement.

Key value for chemical safety assessment

Biodegradation in water:

not biodegradable

Additional information

No experimental studies on the "Biodegradation in water" are available for the substance in itself.

Nevertheless, two studies were conducted on an analogue substance (Similar Substance 01). Further information are reported in the Read Across justification attached to section 13.

 

Inherent biodegradability 

The inherent biodegradability was determined in a Zahn-Wellens, test according to the OECD Guideline for Testing of Chemicals, No. 302B. The test has been performed in compliance with the Procedures and Principles of Good Laboratory. The test substance and the reference substance Diethylenglycol, respectively, were tested in concentrations of 100 mg/L ai.

The biodegradation of the test substance after 28 days was between 4% and 16%. The biodegradation of the reference substance after 14 days was 100%.

 

BOD5/COD ratio

Biochemical Oxygen Demand (BOD5) and Chemical Oxygen Demand (COD) are the most commonly used parameters for the characterization of the biodegradability capacity.

COD results are typically higher than BOD5 values, and their ratio varie depending on the characteristics of the substrate. This ratio has been commonly used as an indicator for biodegradation capacity, the "Biodegradability index" (B.I.).

As indicated in ECHA Guidance requirement R.7B, the BOD5 test is a traditional biodegradation test that is now replaced by the ready biodegradability tests. Therefore, this test should not be performed today for assessment of the ready biodegradability of substances.

Older test data may, however, be used when no other degradability data are available.

Studies on BOD5 and COD are available for this substance, therefore they have been used together with the inherent biodegradability OECD 302.B., in the weight of evidence approach for this substance.

COD was measured according to Method A-16. Details of the method have been not reported. The COD measured was 1180 mg/g O2.

BOD5 was measured according to Method A-15. Details of the method have been not reported. The BOD5 measured was 39 mg/g O2.

The ratio BOD5/COD is 0.03.

 

Moreover based on a QSAR prediction, the target substance is not readily biodegradable.