[4-[4,4'-bis(dimethylamino)benzhydrylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium chloride

Endpoint summary

Description of key information

Stability:

Hydrolysis:

Half life of hydrolysis of test chemical N-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride ( CAS no. 548 -62 -9) is predicted using OECD QSAR tool box v.3.3 using log kow as primary descriptor. The half life of Hydrolysis of chemical N-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride estimated  was 291.447 days at 50 deg. C. By this value it is concluded that this test chemical is expected to show negligible hydrolysis.

Biodegradation:

Biodegradtion in water:

The test chemical 4-{bis[4-(dimethylamino)phenyl]methylidene}-N,N-dimethylcyclohexa-2,5-dien-1-iminium chloride ( CAS no. 548 -62 -9) showed 3.6 % biodegradation by using parameter CO2 evolution in 28 days. By this percent biodegrdation value this chemical is considered as not readily biodegradable.

Biodegradtion in water and sediments:

Estimation Programs Interface (EPI Suite, 2017) prediction model was run to predict the half-life in water and sediment for the test compound N-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride (CAS No: 548 -62 -9) .If released in to the environment, 2.22 % of the chemical will partition into water according to the Mackay fugacity model level III and the half-life period of the chemical N-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride 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 high whereas the half-life period of N-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride in sediment is estimated to be 541 days (13000 hrs) indicates that test chemicalN-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chlorideis persistent in sediment as well.

Biodegradtion in Soil:

The half-life period ofN-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride(CAS No: 548 -62 -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, 48.8 % of the chemical will partition into soil according to the Mackay fugacity model level III. The half-life period of test chemicalN-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloridein soil is estimated to be 120 days (2880 hrs). Based on this half-life value of test chemicalN-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride, 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.

Bioaccumulation:

Bioaccumulation in aquatic and sediments:

The BCF value of chemical 4-{bis[4-(dimethylamino)phenyl]methylidene}-N,N-dimethylcyclohexa-2,5-dien-1-iminium chloride (CAS no. 548-62-9) was estimated is 3 dimensionless by using log Kow of 0.51 and regression derived equation and it is far less than 2000. So it is concluded that this chemical is non bioaccumulative.

Transport and distribution:

Adsorption and desorption:

The Koc value for chemicalN-(4-{bis[4-(dimethylamino)phenyl]methylidene}-N,N-dimethylcyclohexa-2,5-dien-1-iminium chloride is estimated by using Structure estimation method based on molecular connectivity indices. The estimated Koc value is 610000 dimensionless and log Koc is 5.7853. Based on this value,N-(4 -{bis[4-(dimethylamino)phenyl]methylidene}-N,N-dimethylcyclohexa-2,5-dien-1-iminium chloride is expected  to have very strong sorption to soil and sediment and therefore have negligible migration potential to ground water.

Additional information

Stability:

Hydrolysis:

Predicted data for target compound N-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride( CAS no.548 -62 -9) from OECD QSAR tool box.v.3.3 and supporting study for its read across chemical were reviewed as follow.

 

Half life of hydrolysis of test chemical N-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride ( CAS no. 548 -62 -9) is predicted using OECD QSAR tool box v.3.3 using log kow as primary descriptor. The half life of Hydrolysis of chemical N-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride estimated  was 291.447 days at 50 deg. C. By this value it is concluded that this test chemical is expected to show negligible hydrolysis.

 

In a supporting study from authoritative database ( Comptox chemistry Dashboard, 2017) the hydrolysis rate constant of read across chemical 4-[(4-dimethylaminophenyl)-phenylmethylidene]cyclohexa-2,5-dien-1-ylidene]-dimethylazanium chloride estimated is 4.31e-11 cm3/mol/sec as this hydrolysis rate constant is very less this chemical shows negligible hydrolysis and it is also supported by data obtained from authoritative database ( HSDB) that this chemical lack hydrolyzable functional group and does not undergo hydrolysis.

 

By considering results of both studies it is concluded that the target chemical N-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride is shows negligible hydrolysis.

Biodegradation:

Biodegradtion in water:

Results of different experimental studies and predicted data studies of target chemical 4-{bis[4-(dimethylamino)phenyl]methylidene}-N,N-dimethylcyclohexa-2,5-dien-1-iminium chloride ( CAS no. 548 -62 -9) and results of experimental studies for its closest read across chemicals with log Kow as primary descriptor were reviewed as follow.

 

In a experimental study done by Clariant Chemical (India) limited in 2010. The test chemical 4-{bis[4-(dimethylamino)phenyl]methylidene}-N,N-dimethylcyclohexa-2,5-dien-1-iminium chloride (CAS no. 548-62-9) showed 3.6 % biodegradation by using parameter CO2 evolution in 28 days. By this percent biodegradation value this chemical is considered as not readily biodegradable.

 

In another study done by Chiing-Chang Chen , Hung-Ju Liao, Chiu-Yu Cheng , Chia-Yuen Yen and Ying-Chien Chung published in journal Biotechnology letters in 2007 biodegradation experiment was performed to test biodegradability of test chemical (4-(4,4'-Bis(dimethylamino)benzhydrylidene)cyclohexa-2,5-dien-1-ylidene)dimethylammonium chloride (CAS no. 548-62-9) by taking bacteria pseudomonas putidaas a inoculum isolated from waste water of dye manufacturing company at concentration of 6×107cfu/mL. Prior to the experiment, the bacterial cells were pre-cultivated in nutrient broth for 12 h. The initial concentration of test chemical taken was 0.022 mg/L and pH was 7.5 and temperature was 37 o C. After 7 days amount of residual chemical was analysed by using HPLC and percent biodegradation was calculated. Percent Biodegradation of test chemical (4-(4,4'-Bis(dimethylamino)benzhydrylidene)cyclohexa-2,5-dien-1-ylidene)dimethylammonium, chloride obtained was 78.5 % by test material analysis parameter. By percent biodegradation this test chemical is considered as readily biodegradable by pseudomonas putida.

 

In next study prediction was done to check biodegradability of test chemical N-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride ( CAS no. 548-62-9) using OECD QSAR tool box v.3.3 using log kow as primary descriptor. The biodegradation percentage of test chemical N-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride obtained was only 3 %  by considering BOD parameter  and microorganisms as inoculum in 28 days. By considering this value of percent biodegradability it is concluded that test chemical N-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride is not readily biodegradable.

 

Another prediction done by using Estimation Programs Interface Suite (EPI suite, 2017)to predict the biodegradation potential of the target chemical N-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminiumchloride(CAS No: 548-62-9) 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 as Biowin 1-7, respectively) of the BIOWIN v4.10 software. The results indicate that the chemical N-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride is not readily biodegradable.

 

In a supporting weight of evidence study done for read across chemical 4-[4 (dimethylamino)benzenecarboximidoyl]-N,N-dimethylaniline hydrochloride (CAS no. 2465-27-2) biodegradation potential was determined by taking sludge as inoculums at 30 mg/L concentration. Biodegradation was analyzed by using BOD and UV-vis parameter. The initial concentration of read cross chemical was 100 mg/L and study design is of standard type. After 2 weeks (14 days) test chemical 4-[4-(dimethylamino)benzenecarboximidoyl]-N,N-dimethylaniline hydrochloride showed 0% biodegradation by BOD and 12% by UV-vis parameter so it is concluded that test chemical 4-[4-(dimethylamino)benzenecarboximidoyl]-N,N-dimethylaniline hydrochloride is not readily biodegradable.

 

In another supporting weight of evidence study done for another read across chemical benzyl(triphenyl)phosphanium chloride (CAS no.1100-88-5)biodegradation test was carried out by taking sludge as inoculums at 30 mg/L concentration and O2 consumption (BOD), TOC removal and test material analysis by HPLC as parameters. The initial concentration of read cross chemical was 100 mg/L and by taking standard test equipment. After 4 weeks (28 days) read across chemical benzyl(triphenyl)phosphanium chloride showed 0% biodegradation by all three parameters in 28 days. So it is concluded that this read across chemical is not readily biodegradable.

 

By considering all the results of above mentioned study of target chemical 4-{bis[4-(dimethylamino)phenyl]methylidene}-N,N-dimethylcyclohexa-2,5-dien-1-iminium chloride (CAS no. 548-62-9) and supporting weight of evidence study of its read across chemicals percentage of biodegradation was very low ( below 20 %) therefore it is concluded that this test chemical not readily biodegradable but in one study of target chemical published in Biotechnology letters journal shows contradicting results i.e., target chemical readily biodegradable as its degradation percentage was very high ( 78.5%) in 7 days by bacteriapseudomonas putidathe probable reason for this result is that the target chemical shows cytotoxicity to many microorganisms as reported by Michaels and Lewis (1986) and gram negative bacteria Pseudomonas putidais resistance to many antibiotics and chemical hence it is able to degrade it.

However in environment there are many type of microorganisms which not resistance to target chemical which shows cytotoxicity to many organisms. Hence by considering results of other above mentioned studies and studies of read across chemicals it is concluded that target chemical 4-{bis[4-(dimethylamino)phenyl]methylidene}-N,N-dimethylcyclohexa-2,5-dien-1-iminium chloride (CAS no. 548-62-9) is expected to be not readily biodegradable.

Biodegradtion in water and sediments:

Estimation Programs Interface (EPI Suite, 2017) prediction model was run to predict the half-life in water and sediment for the test compound N-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride (CAS No: 548 -62 -9) .If released in to the environment, 2.22 % of the chemical will partition into water according to the Mackay fugacity model level III and the half-life period of the chemical N-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride 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 high whereas the half-life period of N-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride in sediment is estimated to be 541 days (13000 hrs) indicates that test chemicalN-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chlorideis persistent in sediment as well.

Biodegradtion in Soil:

The half-life period ofN-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride(CAS No: 548 -62 -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, 48.8 % of the chemical will partition into soil according to the Mackay fugacity model level III. The half-life period of test chemicalN-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloridein soil is estimated to be 120 days (2880 hrs). Based on this half-life value of test chemicalN-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride, 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.

Bioaccumulation:

Bioaccumulation in aquatic and sediments:

Various predicted data for the target compound 4-{bis[4-(dimethylamino)phenyl]methylidene}-N,N-dimethylcyclohexa-2,5-dien-1-iminium chloride (CAS no. 548-62-9) and supporting weight of evidence studies for its read across substance were reviewed for the bioaccumulation end point which are summarized as below:

In the study from HSDB ( Hazardous Substance Data Bank, 2017).The BCF value of chemical 4-{bis[4-(dimethylamino)phenyl]methylidene}-N,N-dimethylcyclohexa-2,5-dien-1-iminium chloride (CAS no. 548-62-9) was estimated is 3 dimensionless by using log Kow of 0.51 and regression derived equation.

 

In a Prediction done from BCFBAF Program (v3.00) model of EPI suite v.3.01 ( Estimation Program Interface, 2017) the estimated bio concentration factor (BCF) for N-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride is 3.162 L/kg wet.

 

Another predicted data study done from CompTox Chemistry Dashboard using OPERA (OPEn (quantitative) structure-activity Relationship Application)  V1.02 model in which calculation based on PaDEL descriptors (calculate molecular descriptors and fingerprints of chemical)  the bioaccumulation i.e BCF for test substance N-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride (CAS no.548-62-9) was estimated to be 39.5 dimensionless the predicted BCF result based on the 5 OECD principles.

 

In the supporting weight of evidence study from authoritative database ( J check, 2017). Bioaccumulation test was conducted for 6 weeks for determination the bioconcentration factor (BCF) of read across substance 4-[4-(dimethylamino)benzenecarboximidoyl]-N,N-dimethylaniline hydrochloride(CAS no 2465-27-2) on test organism Cyprinus carpio. Recovery ratio : Test water : 1st concentration area : 90.2 % , 2nd concentration area : 90.0% Fish : 54.0%, ­ Limit of detection :  Fish : 0.012 microg/g

And Nominal concentrations used in the study as - 1st Concentration area: 0.1 mg/L, 2nd Concentration area : 0.01 mg/L and Range finding study was carried out on Rice fish (Oryzias latipes) TLm(48h)5 .3 ppm(w/v). Thus according to static Fish Test the BCF value for read across substance 4-[4-(dimethylamino)benzenecarboximidoyl]-N,N-dimethylaniline hydrochloride was observed to be 3.8-11 L/kg at dose concentration 0.1 ppm(w/v) and 6.1-16 L/kg at dose concentration 0.01 ppm(w/v) on test organism Cyprinus carpio during 6 weeks period. These BCF values indicate that the read across substance4-[4 -(dimethylamino)benzenecarboximidoyl]-N,N-dimethylaniline hydrochloride is not bioaccumulative in fish and food chain.

 

In another supporting weight of evidence study from authoritative database HSDB ( Hazardous Substance Data Bank, 2017) The BCF value of read across chemical 4-[(4-dimethylaminophenyl)-phenylmethylidene]cyclohexa-2,5-dien-1-ylidene]-dimethylazanium chloride (CAS no. 569-64-2) was estimated is 3 dimensionless by using log Kow of 0.62 and regression derived equation and it is far less than 2000 so it is concluded that this read across chemical is non bioaccumulative.

 

On the basis of above results for target chemical 4-{bis[4-(dimethylamino)phenyl]methylidene}-N,N-dimethylcyclohexa-2,5-dien-1-iminium chloride (CAS no. 548-62-9) (from HSDB, EPI suite and CompTox Chemistry Dashboard, 2017) and for its read across substance from authoritative databases (HSDB and J Check) it can be concluded that the BCF value of test substance 4-{bis[4-(dimethylamino)phenyl]methylidene}-N,N-dimethylcyclohexa-2,5-dien-1-iminium chloride ranges from 3 to 39.5 dimensionless which does not exceed the bioconcentration threshold of 2000, indicating that the chemical 4-{bis[4-(dimethylamino)phenyl]methylidene}-N,N-dimethylcyclohexa-2,5-dien-1-iminium chloride is not expected to bioaccumulate in the food chain.

Transport and distribution:

Adsorption and desorption:

Different studies results for target chemical N-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride( CAS no.548 -62 -9) and supporting study for its read across chemical for adsorption endpoint were reviewed as follow.

 

The Koc value for chemical N-(4-{bis[4-(dimethylamino)phenyl]methylidene}-N,N-dimethylcyclohexa-2,5-dien-1-iminium chloride is estimated by using Structure estimation method based on molecular connectivity indices . The estimated Koc value is 610000 dimensionless and log Koc is 5.7853.

 

Another study was done and Soil Adsorption Coefficient i.e Koc value of N-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride (CAS no. 548 -62-9) was estimated using EPI suite, 2017 KOCWIN Program (v2.00) as 467800 L/kg(log Koc=5.670)  by means of MCI method at 25 deg.C. T

 

In a supporting weight of evidence study the Koc value for read across chemical4-[4-(dimethylamino)benzenecarboximidoyl]-N,N-dimethylaniline hydrochloride( CAS No. 2465-27-2) was estimated using structure estimation method. The estimated Koc value is 50000 dimensionless and log Koc is 4.6989.

 

On the basis of above overall results for target chemical N-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride( CAS no.548 -62 -9) (from HSDB and EPI suite, 2017), it can be concluded that the Koc value of test substance N-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride ranges from 50000 to 610000 and log koc ranges from 4.69 to 5.7853 indicating that the test chemical of N-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1 - ylidene)-N-methylmethanaminium chloride has very strong sorption to soil and sediment and therefore have negligible to negligible migration potential to groundwater