Tetrasodium [μ-[[3,3'-[(3,3'-dihydroxy[1,1'-biphenyl]-4,4'-diyl)bis(azo)]bis[5-amino-4-hydroxynaphthalene-2,7-disulphonato]](8-)]]dicuprate(4-)

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Endpoint:

biodegradation in water: screening tests

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

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 limited documentation / justification

Justification for type of information:

The suporting QMRF report has been attached

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 C (Ready Biodegradability: Modified MITI Test (I))

Principles of method if other than guideline:

The prediction was done by using OECD QSAR tool box v3.3

GLP compliance:

not specified

Oxygen conditions:

not specified

Inoculum or test system:

other: Microorganisms

Duration of test (contact time):

28 d

Parameter followed for biodegradation estimation:

other: BOD

Key result

Parameter:

other: BOD

Value:

0.625

Sampling time:

28 d

Remarks on result:

other: other details not available

Details on results:

Percent biodegradability of test chemical Copper,[tetrahydrogen-3,3'-[(3,3'-dihydroxy-4,4'-biphenylylene)bis(azo)]bis[5-amino-4-hydroxy-2,7-naphthalenedisulfonato](4-)]di-,tetrasodium salt (7CI) (Direct Blue) was estimated to be 0.625% by considering BOD as parameter in 28 days.

The prediction was based on dataset comprised from the following descriptors: BOD
Estimation method: Takes average value from the 8 nearest neighbours
Domain  logical expression:Result: In Domain

((((((("a" or "b" )  and "c" )  and "d" )  and ("e" and ( not "f") )  )  and ("g" and ( not "h") )  )  and ("i" and ( not "j") )  )  and ("k" and "l" )  )

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as Non-covalent interaction AND Non-covalent interaction >> DNA intercalation AND Non-covalent interaction >> DNA intercalation >> Fused-Ring Primary Aromatic Amines AND Radical AND Radical >> Radical mechanism via ROS formation (indirect) AND Radical >> Radical mechanism via ROS formation (indirect) >> Fused-Ring Primary Aromatic Amines AND SN1 AND SN1 >> Nucleophilic attack after metabolic nitrenium ion formation AND SN1 >> Nucleophilic attack after metabolic nitrenium ion formation >> Fused-Ring Primary Aromatic Amines by DNA binding by OASIS v.1.3

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as SN1 AND SN1 >> Nitrenium Ion formation AND SN1 >> Nitrenium Ion formation >> Primary aromatic amine by DNA binding by OECD

Domain logical expression index: "c"

Referential boundary: The target chemical should be classified as Does NOT Biodegrade Fast by Biodeg probability (Biowin 1) ONLY

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as Does NOT Biodegrade Fast by Biodeg probability (Biowin 7) ONLY

Domain logical expression index: "e"

Referential boundary: The target chemical should be classified as Non binder, MW>500 by Estrogen Receptor Binding

Domain logical expression index: "f"

Referential boundary: The target chemical should be classified as Moderate binder, NH2 group by Estrogen Receptor Binding

Domain logical expression index: "g"

Referential boundary: The target chemical should be classified as Non binder, MW>500 by Estrogen Receptor Binding

Domain logical expression index: "h"

Referential boundary: The target chemical should be classified as Weak binder, NH2 group by Estrogen Receptor Binding

Domain logical expression index: "i"

Referential boundary: The target chemical should be classified as SHOULD NOT BE PROFILED by Aquatic toxicity classification by ECOSAR

Domain logical expression index: "j"

Referential boundary: The target chemical should be classified as Acid moiety by Aquatic toxicity classification by ECOSAR

Domain logical expression index: "k"

Parametric boundary:The target chemical should have a value of Water Solubility which is >= -4.64 mg/L

Domain logical expression index: "l"

Parametric boundary:The target chemical should have a value of Water Solubility which is <= 5.29E003 mg/L

Validity criteria fulfilled:

not specified

Interpretation of results:

not readily biodegradable

Conclusions:

Percent biodegradability of test chemical Copper,[tetrahydrogen-3,3'-[(3,3'-dihydroxy-4,4'-biphenylylene)bis(azo)]bis[5-amino-4-hydroxy-2,7-naphthalenedisulfonato](4-)]di-,tetrasodium salt (7CI) (Direct Blue) was estimated to be 0.625% by considering BOD as parameter and microorganisms as inoculum in 28 days. On the basis of percent biodegradability value it can be concluded that test chemical can be considered as not readily biodegradable.

Executive summary:

Biodegradability of test chemical Copper,[tetrahydrogen-3,3'-[(3,3'-dihydroxy-4,4'-biphenylylene)bis(azo)]bis[5-amino-4-hydroxy-2,7-naphthalenedisulfonato](4-)]di-,tetrasodium salt (7CI) (Direct Blue) CAS no.28407 -37 -6 was predicted by using OECD QSAR tool box v 3.3 by considering eight closest read across chemicals with log Kow as primary descriptor. Percent biodegradability of test chemical  Copper,[tetrahydrogen-3,3'-[(3,3'-dihydroxy-4,4'-biphenylylene)bis(azo)]bis[5-amino-4-hydroxy-2,7-naphthalenedisulfonato](4-)]di-,tetrasodium salt (7CI) (Direct Blue) was estimated to be 0.625% by considering BOD as parameter and microorganisms as inoculum in 28 days. On the basis of percent biodegradability value it can be concluded that  test chemical can be considered as not readily biodegradable.

Description of key information

Biodegradability of test chemical Copper,[tetrahydrogen-3,3'-[(3,3'-dihydroxy-4,4'-biphenylylene)bis(azo)]bis[5-amino-4-hydroxy-2,7-naphthalenedisulfonato](4-)]di-,tetrasodium salt (7CI) (Direct Blue) CAS no.28407 -37 -6 was predicted by using OECD QSAR tool box v 3.3 by considering eight closest read across chemicals with log Kow as primary descriptor. Percent biodegradability of test chemical Copper,[tetrahydrogen-3,3'-[(3,3'-dihydroxy-4,4'-biphenylylene)bis(azo)]bis[5-amino-4-hydroxy-2,7-naphthalenedisulfonato](4-)]di-,tetrasodium salt (7CI) (Direct Blue) was estimated to be 0.625% by considering BOD as parameter and microorganisms as inoculum in 28 days. On the basis of percent biodegradability value it can be concluded that  test chemical can be considered as not readily biodegradable.

Key value for chemical safety assessment

Biodegradation in water:

under test conditions no biodegradation observed

Additional information

Predicted data studies for target chemical Copper,[tetrahydrogen-3,3'-[(3,3'-dihydroxy-4,4'-biphenylylene)bis(azo)]bis[5-amino-4-hydroxy-2,7-naphthalenedisulfonato](4-)]di-,tetrasodium salt (7CI) (Direct Blue) CAS no.28407 -37 -6 and experimental studies for its structurally similar read across chemical have been conducted for biodegradation in water endpoint and their results are summarized below.

 

In first predicted data study the biodegradability of test chemical Copper,[tetrahydrogen-3,3'-[(3,3'-dihydroxy-4,4'-biphenylylene)bis(azo)]bis[5-amino-4-hydroxy-2,7-naphthalenedisulfonato](4-)]di-,tetrasodium salt (7CI) (Direct Blue) CAS no.28407 -37 -6 was predicted by using OECD QSAR tool box v 3.3 by considering eight closest read across chemicals with log Kow as primary descriptor. Percent biodegradability of test chemical  Copper,[tetrahydrogen-3,3'-[(3,3'-dihydroxy-4,4'-biphenylylene)bis(azo)]bis[5-amino-4-hydroxy-2,7-naphthalenedisulfonato](4-)]di-,tetrasodium salt (7CI) (Direct Blue) was estimated to be 0.625% by considering BOD as parameter and microorganisms as inoculum in 28 days. On the basis of percent biodegradability value it can be concluded that test chemical can be considered as not readily biodegradable.

 

Another predicted data study was done by using Estimation Programs Interface Suite (EPI suite, 2017) in this study the EPI suite was run to predict the biodegradation potential of the test compound Copper,[tetrahydrogen-3,3'-[(3,3'-dihydroxy-4,4'-biphenylylene)bis(azo)]bis[5-amino-4-hydroxy-2,7-naphthalenedisulfonato](4-)]di-,tetrasodium salt (7CI) (CAS no. 28407-37-6) in the presence of mixed populations of environmental microorganisms. The biodegradability of the substance was calculated using seven different models such as Linear Model, Non-Linear Model, Ultimate Biodegradation Timeframe, Primary Biodegradation Timeframe, MITI Linear Model, MITI Non-Linear Model and Anaerobic Model (called Biowin 1-7, respectively) of the BIOWIN v4.10 software. The results indicate that chemical  Copper,[tetrahydrogen-3,3'-[(3,3'-dihydroxy-4,4'-biphenylylene)bis(azo)]bis[5-amino-4-hydroxy-2,7-naphthalenedisulfonato](4-)]di-,tetrasodium salt (7CI) is expected to be not readily biodegradable.

Next study was experimental study and it is done from journal Chemosphere, Vo1.15, No.4, pp 479-491, (1986) by U. Pagga and O. Brown for structurally similar read across chemical chemical tetrasodium 3,3'-[(3,3'-dimethoxy[1,1'-biphenyl]-4,4'-diyl)bis(azo)]bis[4,5-dihydroxynaphthalene-2,7-disulphonate](CAS no.4198 -19 -0) in this study the aerobic biodegradation experiment was performed for chemical tetrasodium 3,3'-[(3,3'-dimethoxy[1,1'-biphenyl]-4,4'-diyl)bis(azo)]bis[4,5-dihydroxynaphthalene-2,7-disulphonate] using activated sludge at concentration 0.5 g/L dry material as inoculums and initial concentration of chemical taken was 100mg/L for 42 days. By considering DOC removal parameter test chemical showed -17 % degradation in 42 days. The read across chemical tetrasodium 3,3'-[(3,3'-dimethoxy[1,1'-biphenyl]-4,4'-diyl)bis(azo)]bis[4,5-dihydroxynaphthalene-2,7-disulphonate] belongs to D category according to table 1 and 2 as its limit value falls in that range. This percentage value is in negative So it is concluded that Tetrasodium 3,3'-[(3,3'-dimethoxy[1,1'-biphenyl]-4,4'-diyl)bis(azo)]bis[4,5-dihydroxynaphthalene-2,7-disulphonate](CAS no. 4198 -19 -0) is not readily biodegradable.

 

Similarly one more experimental study was also done from same source as mentioned above for structurally similar read across chemical tetrasodium;3-[[4-[[4-[(2E)-2-(6-amino-1-oxo-3-sulfonatonaphthalen-2-ylidene)hydrazinyl]-6-sulfonatonaphthalen-1-yl]diazenyl]naphthalen-1-yl]diazenyl]naphthalene-1,5-disulfonate (CAS no. 4399 -55 -7) in this study the aerobic biodegradation experiment was performed for read across chemical tetrasodium;3-[[4-[[4-[(2E)-2-(6-amino-1-oxo-3-sulfonatonaphthalen-2-ylidene)hydrazinyl]-6-sulfonatonaphthalen-1-yl]diazenyl]naphthalen-1-yl]diazenyl]naphthalene-1,5-disulfonate using activated sludge at concentration 0.5 g/L dry material as inoculums and initial concentration of chemical taken was 100 mg/L for 42 days. By considering DOC removal parameter test chemical showed -27 % degradation in 42 days. This percentage value is in negative So it is concluded that read across chemical tetrasodium;3-[[4-[[4-[(2E)-2-(6-amino-1-oxo-3-sulfonatonaphthalen-2-ylidene)hydrazinyl]-6-sulfonatonaphthalen-1-yl]diazenyl]naphthalen-1-yl]diazenyl]naphthalene-1,5-disulfonate is not readily biodegradable.

 

Another experimental study was done from authoritative database (J check, 2017) in this study Biodegradation experiment was conducted for 14 days for evaluating the percentage biodegradability of read across substance disodium 4 -hydroxy-7 -{[(5 -hydroxy-7 -sulfonato-2 -naphthyl)carbamoyl]amino}naphthalene-2 -sulfonate (CAS no. 20324 -87 -2). Concentration of inoculum i.e, sludge used was 30 mg/l and initial test substance conc. used in the study was 100 mg/l. The percentage degradation of read across substance disodium 4 -hydroxy-7 -{[(5 -hydroxy-7 -sulfonato-2 -naphthyl)carbamoyl]amino}naphthalene-2 -sulfonate was determined to be 0 and 1.3 % by BOD and TOC removal parameter respectively in 14 days. Thus, based on percentage degradation, disodium 4 -hydroxy-7 -{[(5 -hydroxy-7 -sulfonato-2 -naphthyl)carbamoyl]amino}naphthalene-2 -sulfonate is considered to be not readily biodegradable in nature.

 

By considering results of predicted data for target chemical and experimental studies of structurally similar read across chemicals it can be concluded that test chemical Copper,[tetrahydrogen-3,3'-[(3,3'-dihydroxy-4,4'-biphenylylene)bis(azo)]bis[5-amino-4-hydroxy-2,7-naphthalenedisulfonato](4-)]di-,tetrasodium salt (7CI) (Direct Blue) CAS no.28407 -37 -6 is not readily biodegradable.