[4-[[4-(dimethylamino)phenyl][4-(methylamino)phenyl]methylene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium acetate

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:

equivalent or similar 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: N-(4-{[4-(dimethylamino)phenyl][4-(methylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium acetate; 4-{[4-(dimethylamino)phenyl][4-(methylamino)phenyl]methylidene}-N,N-dimethylcyclohexa-2,5-dien-1-iminium acetate
- Molecular formula: C24H28N3.C2H3O2
- Molecular weight: 417.5499 g/mol
- Smiles notation: CC(=O)[O-].CNc1ccc(cc1)C(=C2C=CC(=[N+](C)C)C=C2)c3ccc(cc3)N(C)C
- InChI: 1S/C24H27N3.C2H4O2/c1-25-21-12-6-18(7-13-21)24(19-8-14-22(15-9-19)26(2)3)20-10-16-23(17-11-20)27(4)5;1-2(3)4/h6-17H,1-5H3;1H3,(H,3,4)
- Substance type: Organic
- Physical state: Liquid

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: % degradation (BOD)

Value:

0

Sampling time:

28 d

Remarks on result:

other: Other details not known

Details on results:

Test substance undergoes 0% 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" or "d" )  and "e" )  and "f" )  and "g" )  and ("h" and "i" )  )

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as Acetoxy OR Alkene OR Ammonium salt OR Aromatic amine OR Aryl OR Carboxylic acid by Organic Functional groups ONLY

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as Acetoxy OR Alkene OR Ammonium salt OR Aromatic amine OR Overlapping groups by Organic Functional groups (nested) ONLY

Domain logical expression index: "c"

Referential boundary: The target chemical should be classified as Aliphatic Carbon [CH] OR Aliphatic Carbon [-CH2-] OR Aliphatic Carbon [-CH3] OR Aliphatic Nitrogen, one aromatic attach [-N] OR Amino, aliphatic attach [-N<] OR Aromatic Carbon [C] OR Carbonyl, aliphatic attach [-C(=O)-] OR Miscellaneous sulfide (=S) or oxide (=O) OR Olefinic carbon [=CH- or =C<] by Organic functional groups (US EPA) ONLY

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as Amine OR Anion OR Aromatic compound OR Carbonic acid derivative OR Carboxylic acid derivative OR Carboxylic acid salt OR Cation OR Secondary amine OR Secondary mixed amine (aryl, alkyl) OR Tertiary amine OR Tertiary mixed amine by Organic functional groups, Norbert Haider (checkmol) ONLY

Domain logical expression index: "e"

Referential boundary: The target chemical should be classified as Not calculated by Biodeg BioHC half-life (Biowin) ONLY

Domain logical expression index: "f"

Referential boundary: The target chemical should be classified as weeks - months by Biodeg primary (Biowin 4) ONLY

Domain logical expression index: "g"

Similarity boundary:Target: CC(=O)O{-}.N{+}(C)(C)=C1C=CC(=C(c2ccc(NC)cc2)c2ccc(N(C)C)cc2)C=C1
Threshold=50%,
Dice(Atom centered fragments)
Atom type; Count H attached; Hybridization

Domain logical expression index: "h"

Parametric boundary:The target chemical should have a value of Molecular weight which is >= 173 Da

Domain logical expression index: "i"

Parametric boundary:The target chemical should have a value of Molecular weight which is <= 423 Da

Validity criteria fulfilled:

not specified

Interpretation of results:

under test conditions no biodegradation observed

Conclusions:

The test chemical N-(4-{[4-(dimethylamino)phenyl][4-(methylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium acetate was estimated to be not readily biodegradable in water.

Executive summary:

Biodegradability of N-(4-{[4-(dimethylamino)phenyl][4-(methylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium acetate

(CAS no. 84434 -47 -9) is predicted using OECD QSAR toolbox version 3.3 with logKow as the primary descriptor. Test substance undergoes 0% degradation by BOD in 28 days. Thus, based on percentage degradation, the test chemical N-(4 -{[4 -dimethylamino)][4 -(methylamino)phenyl]methylene}cyclohexa-2,5 -dien-1 -ylidene)-N-methylmethanaminium acetate was estimated to be not readily biodegradable in water.

Description of key information

Biodegradability of N-(4-{[4-(dimethylamino)phenyl][4-(methylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium acetate

(CAS no. 84434 -47 -9) is predicted using OECD QSAR toolbox version 3.3 (2017) with logKow as the primary descriptor. Test substance undergoes 0% degradation by BOD in 28 days. Thus, based on percentage degradation, the test chemical N-(4 -{[4 -dimethylamino)][4 -(methylamino)phenyl]methylene} cyclohexa-2,5 -dien-1 -ylidene)-N-methylmethanaminium acetate 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 N-(4 -{[4 -(dimethylamino)phenyl][4 -(methylamino)phenyl]methylene}cyclohexa-2,5 -dien-1 -ylidene)-N-methylmethanaminium acetate(CAS No. 84434 -47 -9) and various 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 N-(4-{[4-(dimethylamino)phenyl][4-(methylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium acetate(CAS No. 84434-47-9) was estimated.Test substance undergoes 0% degradation by BOD in 28 days. Thus, based on percentage degradation, the test chemical N-(4 -{[4 -dimethylamino)][4 -(methylamino)phenyl]methylene}cyclohexa-2,5 -dien-1 -ylidene)-N-methylmethanaminium acetate 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 N-(4 -{[4 -(dimethylamino)phenyl][4 -(methylamino)phenyl]methylene}cyclohexa-2,5 -dien-1 -ylidene)-N-methylmethanaminium acetate(CAS No. 84434 -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 N-(4 -{[4 -(dimethylamino)phenyl][4 -(methylamino)phenyl] methylene}cyclohexa-2,5 -dien-1 -ylidene)-N-methylmethanaminium acetate is expected to be not readily biodegradable.

 

In a supporting weight of evidence study from peer reviewed journal (Toshihide Saito et. al, 1984) for the read across chemical 4,4'-carbonimidoylbis (N,N-dimethylaniline) hydrochloride (CAS no. 2465 -27 -2), biodegradation experiment was conducted for evaluating the percentage biodegradability of read across substance 4,4'-carbonimidoylbis(N,N-dimethylaniline) hydrochloride. Activated sludge was used as a test inoculum obtained from municipal sewage. Test substance of conc. 500 mg/l was prepared and diluted as needed. The COD measurement was performed by the potassium dichromate reflux method based on Japanese Industrial Standards. In the BOD measurement, a sample solution was taken into a container. Then JIS-BOD testing solutions, i.e. 3 ml of A solution and 1 ml of B, C, D solutions were added to the sample solution, respectively. Then 5 ml of the supernatant of the municipal sewage activated sludge was added to the sample solution and diluted to 300 ml with water. Immediately, the BOD-time curve was recorded at 20~ using an Ohkura OM-200I type coulometer. The TOC measurement was carried out by a Yanagimoto TOC-ILW.BOD5, COD, ThOD and TOC value of the read across chemical was determined to be 0.038, 1.42, 2.50 and 0.32 g/g, respectively. The BOD5/TOC ratio of read across chemical was determined to be 0.12 (i.e. ranges in between 0.08-0.89), indicating that the chemical is highly resistant to aerobic biodegradation. Thus, based on this value BOD5/TOC value, it can be concluded that the chemical 4,4'-carbonimidoylbis(N,N-dimethylaniline) hydrochloride is not readily biodegradable in nature.

 

For the same read across chemical 4,4'-carbonimidoylbis(N,N-dimethylaniline) hydrochloride (CAS no. 2465-27-2), biodegradation study was conducted for 14 days for evaluating the percentage biodegradability of read across substance 4,4'-carbonimidoylbis(N,N-dimethylaniline) hydrochloride. (CAS no. 2465-27-2) (J-CHECK, 2017). 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 test substance was determined to 0 and 12% by BOD and UV-Vis parameter in 14 days. Thus, based on percentage degradation, 4,4'-carbonimidoylbis(N,N-dimethylaniline) hydrochloride is considered to be not readily biodegradable in nature.

 

Another biodegradation study (from authoritative databaseJ-CHECK, 2017)was conducted for 28 days for evaluating the percentage biodegradability of read across substance 4,4'-methylenebis(N,N-dimethylaniline) (CAS no. 101 -61 -1). 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 test substance was determined to 0 and 1% by BOD and HPLC parameter in 28 days. Thus, based on percentage degradation, 4,4'-methylenebis(N,N-dimethylaniline) is considered to be not readily biodegradable in nature.

 

On the basis of above results for target chemical N-(4 -{[4 -(dimethylamino)phenyl][4 -(methylamino)phenyl]methylene}cyclohexa-2,5 -dien-1 -ylidene)-N-methylmethanaminium acetate (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), it can be concluded that the test substance N-(4 -{[4 -(dimethylamino)phenyl][4 -(methylamino)phenyl]methylene}cyclohexa-2,5 -dien-1 -ylidene)-N-methylmethanaminium acetate can be expected to be not readily biodegradable in nature.