3,7-bis(diethylamino)phenoxazin-5-ium tetrachlorozincate (2:1)

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 supporting 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 data is predicted using the OECD QSAR toolbox version 3.3 with logKow as the primary descriptor.

GLP compliance:

not specified

Specific details on test material used for the study:

- Name of test material (IUPAC name): 3,7-bis(diethylamino)phenoxazin-5-ium tetrachlorozincate (2:1)
- Molecular formula: C40H52Cl4N6O2Zn
- Molecular weight: 856.093 g/mol
- Smiles notation: [o+]1c2cc(ccc2nc2ccc(N(CC)CC)cc12)N(CC)CC.[Zn+2].[ClH-].[ClH-].[ClH-].[ClH-].[o+]1c2cc(ccc2nc2c1cc(cc2)N(CC)CC)N(CC)CC
- InChl: 1S/2C20H26N3O.4ClH.Zn/c2*1-5-22(6-2)15-9-11-17-19(13-15)24-20-14-16(23(7-3)8-4)10-12-18(20)21-17;;;;;/h2*9-14H,5-8H2,1-4H3;4*1H;/q2*+1;;;;;+2/p-4
- Substance type: Organic
- Physical state: Solid

Oxygen conditions:

aerobic

Inoculum or test system:

other: Microorganisms

Duration of test (contact time):

28 d

Based on:

not specified

Parameter followed for biodegradation estimation:

other: BOD

Key result

Parameter:

other: BOD

Value:

1.86

Sampling time:

28 d

Remarks on result:

other: Other details not known

Details on results:

Test substance undergoes 1.86% degradation by BOD in 28 days.

The prediction was based on dataset comprised from the following descriptors: BOD
Estimation method: Takes average value from the 5 nearest neighbours
Domain  logical expression:Result: In Domain

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

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as Zinc metal and salts by OECD HPV Chemical Categories

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as Soluble complexes of Zinc by US-EPA New Chemical Categories

Domain logical expression index: "c"

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

Domain logical expression index: "d"

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

Domain logical expression index: "e"

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

Domain logical expression index: "f"

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

Domain logical expression index: "g"

Referential boundary: The target chemical should be classified as Non binder, without OH or NH2 group by Estrogen Receptor Binding

Domain logical expression index: "h"

Referential boundary: The target chemical should be classified as Not calculated by Hydrolysis half-life (Kb, pH 7)(Hydrowin) ONLY

Domain logical expression index: "i"

Referential boundary: The target chemical should be classified as No alert found by Protein binding by OECD

Domain logical expression index: "j"

Referential boundary: The target chemical should be classified as Acylation OR Acylation >> Direct Acylation Involving a Leaving group OR Acylation >> Direct Acylation Involving a Leaving group >> Acetates by Protein binding by OECD

Domain logical expression index: "k"

Parametric boundary:The target chemical should have a value of Molecular weight which is >= 580 Da

Domain logical expression index: "l"

Parametric boundary:The target chemical should have a value of Molecular weight which is <= 1.17E003 Da

Validity criteria fulfilled:

not specified

Interpretation of results:

not readily biodegradable

Conclusions:

The test chemical 3,7-bis(diethylamino)phenoxazin-5-ium tetrachlorozincate (2:1) was estimated to be not readily biodegradable in water.

Executive summary:

Biodegradability of 3,7-bis(diethylamino)phenoxazin-5-ium tetrachlorozincate (2:1) (CAS no. 63589 -47 -9) is predicted using QSAR toolbox version 3.3 with logKow as the primary descriptor. Test substance undergoes 1.86% degradation by BOD in 28 days. Thus, based on percentage degradation, the test chemical 3,7-bis(diethylamino)phenoxazin-5-ium tetrachlorozincate (2:1) was estimated to be not readily biodegradable in water.

Description of key information

Biodegradability of 3,7-bis(diethylamino)phenoxazin-5-ium tetrachlorozincate (2:1) (CAS no. 63589 -47 -9) is predicted using QSAR toolbox version 3.3 (2017) with logKow as the primary descriptor. Test substance undergoes 1.86% degradation by BOD in 28 days. Thus, based on percentage degradation, the test chemical 3,7-bis(diethylamino)phenoxazin-5-ium tetrachlorozincate (2:1) was estimated to be not readily biodegradable in water.

Key value for chemical safety assessment

Biodegradation in water:

under test conditions no biodegradation observed

Additional information

Various predicted data for the target compound 3,7-bis(diethylamino)phenoxazin-5-ium tetrachlorozincate (2:1) (CAS No. 63589-47-9) and supporting weight of evidence studies for its closest read across substance with logKow as the primary descriptor were reviewed for the biodegradation end point which are summarized as below:

 

In a prediction done by SSS (2017) using OECD QSAR toolbox version 3.3 with logKow as the primary descriptor, percentage biodegradability of test chemical 3,7-bis(diethylamino)phenoxazin-5-ium tetrachlorozincate (2:1) (CAS No. 63589-47-9) was estimated.Test substance undergoes 1.86% degradation by BOD in 28 days. Thus, based on percentage degradation, the test chemical 3,7-bis(diethylamino)phenoxazin-5-ium tetrachlorozincate (2:1) was estimated to be not readily biodegradable in water.

 

In another prediction using the Estimation Programs Interface Suite (EPI suite, 2017), the biodegradation potential of the test compound 3,7-bis(diethylamino)phenoxazin-5-ium tetrachlorozincate (2:1) (CAS No. 63589-47-9) in the presence of mixed populations of environmental microorganisms was estimated.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 as Biowin 1-7, respectively) of the BIOWIN v4.10 software. The results indicate that chemical 3,7 -bis(diethylamino)phenoxazin-5 -ium tetrachlorozincate (2:1) is expected to be not readily biodegradable.

 

In a supporting weight of evidence study from peer reviewed journal (H. Heukelekian and M. C. Rand, 1955) for the read across chemical [4-[α-[4-(dimethylamino)phenyl]benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium chloride (CAS no. 569-64-2),biodegradation experiment was conducted for 5 days for evaluating the percentage biodegradability of read across substance [4-[α-[4-(dimethylamino)phenyl]benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium chloride using standard dilution method at a temperature of 20°C. Sewage was used as a test inoculum. The 5 day BOD value of chemical [4-[α-[4-(dimethylamino)phenyl]benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium chloride was determined to be 0 g/g. Thus, based on this value, [4-[α-[4-(dimethylamino)phenyl]benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium chloride is considered to be not readily biodegradable in nature.

 

Another biodegradation study was conducted for 14 days for evaluating the percentage biodegradability of the same read across substance [4-[α-[4-(dimethylamino)phenyl]benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium chloride (CAS no. 569-64-2) (EnviChem, 2014). The study was performed according to OECD Guideline 301 C (Ready Biodegradability: Modified MITI Test (I). Activated sludge was used as a test inoculums for the study. Concentration of inoculum i.e, sludge used was 30 mg/l and initial test substance conc. used in the study was 100 mg/l, respectively. The percentage degradation of substance [4-[α-[4-(dimethylamino)phenyl]benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium chloride was determined to be 0.3% by BOD parameter in 14 days. Thus, based on percentage degradation, [4-[α-[4-(dimethylamino)phenyl]benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium chloride is considered to be not readily biodegradable in nature.

 

For the read across chemical sodium 4-[3,6-bis(diethylamino)-2,7-dimethylxanthenium-9-yl]benzene-1,3-disulfonate (CAS no. 3520-42-1) from authoritative database (J-CHECK, 2016), biodegradation experiment was conducted for 28 days for evaluating the percentage biodegradability of read across substance sodium 4 -[3,6 -bis(diethylamino)-2,7 -dimethylxanthenium-9 -yl]benzene-1,3 -disulfonate. The study was performed according to OECD Guideline 301 C (Ready Biodegradability: Modified MITI Test (I) and other guideline “Biodegradation test of a chemical substance using a microorganism etc.” provided in “the Notice on the Test Method Concerning New Chemical Substances", respectively. Concentration of inoculum i.e, activated sludge used was 30 mg/l and initial test substance conc. used in the study was 100 mg/l, respectively. The percentage degradation of substance was determined to be 6, 0 and 0% by O2 consumption, TOC removal, Test mat. analysis and HPLC parameter in 28 days. Thus, based on percentage degradation, sodium 4 -[3,6 -bis(diethylamino)-2,7 -dimethylxanthenium-9 -yl]benzene-1,3 -disulfonate is considered to be not readily biodegradable in nature.

 

In a supporting weight of evidence study from authoritative database (J-CHECK, 2016) for the read across chemical Sodium 3-({[4-([4-(dimethylamino)phenyl]{4-[ethyl(3-sulfonatobenzyl)amino]phenyl}methylene)cyclohexa-2,5-dien-1-ylidene](ethyl)ammonio}methyl)benzenesulfonate (CAS no. 1694-09-3), biodegradation experiment was conducted for 28 days for evaluating the percentage biodegradability of read across substance sodium 3 -({[4 -([4 -(dimethylamino)phenyl]{4 -[ethyl(3 -sulfonatobenzyl)amino]phenyl}methylene)cyclohexa-2,5 -dien-1 -ylidene](ethyl)ammonio}methyl)benzenesulfonate. Concentration of inoculum i.e, activated sludge used was 30 mg/l and initial test substance conc. used in the study was 100 mg/l, respectively. The percentage degradation of substance was determined to be 1, 4 and 0% by BOD, TOC removal and HPLC parameter in 28 days. Thus, based on percentage degradation, 3 -({[4 -([4 -(dimethylamino)phenyl]{4 -[ethyl(3 -sulfonatobenzyl)amino]phenyl}methylene)cyclohexa-2,5 -dien-1-ylidene](ethyl)ammonio}methyl) benzenesulfonate is considered to be not readily biodegradable in nature.

 

On the basis of above results for target chemical 3,7-bis(diethylamino)phenoxazin-5-ium tetrachlorozincate (2:1) (from OECD QSAR toolbox version 3.3 and EPI suite, 2017) and for its read across substance (from peer reviewed journal and authoritative database J-CHECK & EnviChem), it can be concluded that the test substance 3,7-bis(diethylamino)phenoxazin-5-ium tetrachlorozincate (2:1) can be expected to be not readily biodegradable in nature.