N-phenyl-4-[[4-(phenylamino)phenyl][4-(phenylimino)cyclohexa-2,5-dien-1-ylidene]methyl]aniline monohydrochloride

Endpoint summary

Description of key information

Biodegradation in water

Biodegradability of N-phenyl-4-[[4-(phenylamino)phenyl][4-(phenylimino)cyclohexa-2,5-dien-1-ylidene]methyl]aniline monohydrochloride (CAS no. 2152 -64 -9) is predicted using OECD QSAR toolbox version 3.3 (2017) with logKow as the primary descriptor. Test substance undergoes 0.286% degradation by BOD in 28 days. Thus, based on percentage degradation, the test chemical N-phenyl-4-[[4-(phenylamino)phenyl][4-(phenylimino)cyclohexa-2,5-dien-1-ylidene]methyl]aniline monohydrochloride was estimated to be not readily biodegradable in water.

Biodegradation in water and sediment

Estimation Programs Interface (EPI Suite, 2017) prediction model was run to predict the half-life in water and sediment for the test compound N-phenyl-4 -[[4 -(phenylamino) phenyl][4 -(phenylimino)cyclohexa-2,5 -dien-1 -ylidene]methyl]aniline monohydrochloride (CAS No. 2152 -64 -9). If released in to the environment, 1.17% of the chemical will partition into water according to the Mackay fugacity model level III and the half-life period of N-phenyl-4 -[[4 -(phenylamino)phenyl][4 -(phenylimino)cyclohexa-2,5 -dien-1 -ylidene] methyl]aniline monohydrochloride in water is estimated to be 60 days (1440 hrs). The half-life (60 days estimated by EPI suite) indicates that the chemical is persistent in water and the exposure risk to aquatic animals is moderate to high whereas the half-life period of N-phenyl-4 -[[4 -(phenylamino)phenyl][4 -(phenylimino)cyclohexa-2,5 -dien-1 -ylidene]methyl] aniline monohydrochloride in sediment is estimated to be 541.66 days (13000 hrs). Based on this half-life value, it indicates that N-phenyl-4 -[[4 -(phenylamino)phenyl][4 -(phenylimino)cyclo hexa-2,5 -dien-1 -ylidene]methyl]aniline monohydrochloride is persistent in sediment.

Biodegradation in soil

The half-life period of N-phenyl-4-[[4-(phenylamino)phenyl][4-(phenylimino)cyclohexa-2,5-dien-1-ylidene]methyl]aniline monohydrochloride (CAS No. 2152 -64 -9) in soil was estimated using Level III Fugacity Model by EPI Suite version 4.1 estimation database (EPI suite, 2017). If released into the environment, 36.5% of the chemical will partition into soil according to the Mackay fugacity model level III. The half-life period of N-phenyl-4-[[4-(phenylamino)phenyl][4-(phenylimino)cyclohexa-2,5-dien-1-ylidene]methyl]aniline monohydrochloride in soil is estimated to be 120 days (2880 hrs). Based on this half-life value of N-phenyl-4 -[[4 -(phenylamino)phenyl][4 -(phenylimino)cyclohexa-2,5 -dien-1 -ylidene]methyl]aniline monohydrochloride, it is concluded that the chemical is not persistent in the soil environment and the exposure risk to soil dwelling animals is moderate to low.

Additional information

Biodegradation in water

Various predicted data for the target compound N-phenyl-4-[[4-(phenylamino)phenyl][4-(phenylimino)cyclohexa-2,5-dien-1-ylidene]methyl]aniline monohydrochloride (CAS No. 2152-64-9) 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 N-phenyl-4 -[[4 -(phenylamino)phenyl][4 -(phenylimino)cyclohexa-2,5 -dien-1 -ylidene]methyl]aniline monohydrochloride(CAS No. 2152-64-9) was estimated.Test substance undergoes 0.286% degradation by BOD in 28 days. Thus, based on percentage degradation, the test chemical N-phenyl-4 -[[4 -(phenylamino)phenyl][4 -(phenylimino)cyclohexa-2,5 -dien-1 -ylidene]methyl]aniline monohydrochloride 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-phenyl-4 -[[4 -(phenylamino)phenyl][4 -(phenylimino)cyclohexa-2,5 -dien-1 -ylidene]methyl]aniline monohydrochloride (CAS No. 2152-64-9) 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-phenyl-4 -[[4 -(phenylamino)phenyl][4 -(phenylimino)cyclohexa-2,5 -dien-1-ylidene]methyl]aniline monohydrochloride 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 and EnviChem, 2014). 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 read across substance 4,4'-carbonimidoylbis(N,N-dimethylaniline) hydrochloride 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 read across substance 4,4'-methylenebis(N,N-dimethylaniline) 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.

 

In a supporting weight of evidence study for the read across chemical 6-phenyl-1,3,5-triazine-2,4-diamine (CAS no. 91-76-9), biodegradation experiment was conducted for 28 days for evaluating the percentage biodegradability of read across substance 6-phenyl-1,3,5-triazine-2,4-diamine (J-CHECK, 2017 and OECD SIDS, 2001). The study was performed according to OECD Guide-line 301 C "Ready Biodegradability: Modified MITI Test (I)". under aerobic conditions. Aniline was used as a reference substance 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. Reference substance undergoes 66 and 77% degradation in 7 and 14 days, respectively. The percentage degradation of read across substance was determined to be 2, 0 and 1% by BOD, TOC removal and HPLC parameter in 28 days. Thus, based on percentage degradation, 6 -phenyl-1,3,5 -triazine-2,4 -diamine is considered to be not readily biodegradable in nature.

 

On the basis of above results for target chemicalN-phenyl-4-[[4-(phenylamino)phenyl][4-(phenylimino)cyclohexa-2,5-dien-1-ylidene]methyl]aniline monohydrochloride(from OECD QSAR toolbox version 3.3 and EPI suite, 2017) and for its read across substance (from peer reviewed journal, authoritative database J-CHECK, EnviChem, and secondary source OECD SIDS), it can be concluded that the test substance N-phenyl-4-[[4-(phenylamino)phenyl][4-(phenylimino)cyclohexa-2,5-dien-1-ylidene]methyl]aniline monohydrochloride can be expected to be not readily biodegradable in nature.

Biodegradation in water and sediment

Estimation Programs Interface (EPI Suite, 2017) prediction model was run to predict the half-life in water and sediment for the test compound N-phenyl-4 -[[4 -(phenylamino) phenyl][4 -(phenylimino)cyclohexa-2,5 -dien-1 -ylidene]methyl]aniline monohydrochloride (CAS No. 2152 -64 -9). If released in to the environment, 1.17% of the chemical will partition into water according to the Mackay fugacity model level III and the half-life period of N-phenyl-4 -[[4 -(phenylamino)phenyl][4 -(phenylimino)cyclohexa-2,5 -dien-1 -ylidene] methyl]aniline monohydrochloride in water is estimated to be 60 days (1440 hrs). The half-life (60 days estimated by EPI suite) indicates that the chemical is persistent in water and the exposure risk to aquatic animals is moderate to high whereas the half-life period of N-phenyl-4 -[[4 -(phenylamino)phenyl][4 -(phenylimino)cyclohexa-2,5 -dien-1 -ylidene]methyl] aniline monohydrochloride in sediment is estimated to be 541.66 days (13000 hrs). Based on this half-life value, it indicates that N-phenyl-4 -[[4 -(phenylamino)phenyl][4 -(phenylimino)cyclo hexa-2,5 -dien-1 -ylidene]methyl]aniline monohydrochloride is persistent in sediment.

Biodegradation in soil

The half-life period of N-phenyl-4-[[4-(phenylamino)phenyl][4-(phenylimino)cyclohexa-2,5-dien-1-ylidene]methyl]aniline monohydrochloride (CAS No. 2152 -64 -9) in soil was estimated using Level III Fugacity Model by EPI Suite version 4.1 estimation database (EPI suite, 2017). If released into the environment, 36.5% of the chemical will partition into soil according to the Mackay fugacity model level III. The half-life period of N-phenyl-4-[[4-(phenylamino)phenyl][4-(phenylimino)cyclohexa-2,5-dien-1-ylidene]methyl]aniline monohydrochloride in soil is estimated to be 120 days (2880 hrs). Based on this half-life value of N-phenyl-4 -[[4 -(phenylamino)phenyl][4 -(phenylimino)cyclohexa-2,5 -dien-1 -ylidene]methyl]aniline monohydrochloride, it is concluded that the chemical is not persistent in the soil environment and the exposure risk to soil dwelling animals is moderate to low.

On the basis of available information, the test substance N-phenyl-4-[[4-(phenylamino)phenyl][4-(phenylimino)cyclohexa-2,5-dien-1-ylidene]methyl]aniline monohydrochloride can be considered to be not readily biodegradable in nature.