4,4'-carbonimidoylbis[N,N-diethylaniline] monohydrochloride

Endpoint summary

Description of key information

Hydrolysis:

The hydrolytic half-life of 4,4'-carbonimidoylbis[N,N-diethylaniline] monohydrochloride was estimated to be 156.41 days, indicating that it is

very negligibly hydrolysable.

Biodegradation in water

The test item 4,4'-carbonimidoylbis[N,N-diethylaniline] monohydrochloride(CAS No.6358-36-7) undergoes 22.51 % biodegradation after 35 days in

the test condition. Thus, the test item was considered to be primary inherent biodegradable.

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 C.I. Basic Yellow 37 (CAS No. 6358 -36 -7). If released in to the environment, 4.28% of the chemical will partition into water according to the Mackay fugacity model level III and the half-life period of C.I. Basic Yellow 37 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 C.I. Basic Yellow 37 in sediment is estimated to be 541.66 days (13000 hrs). Based on this half-life, it indicates that the chemical C.I. Basic Yellow 37 is persistent in sediment.   

Biodegradation in soil

The half-life period of C.I. Basic Yellow 37 (CAS No. 6358 -36 -7) 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, 62.8% of the chemical will partition into soil according to the Mackay fugacity model level III. The half-life period of C.I. Basic Yellow 37 in soil is estimated to be 120 days (2880 hrs). Based on this half-life value of C.I. Basic Yellow 37, 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: aquatic / sediment:

The estimated bio concentration factor (BCF) for chemical 4,4'-carbonimidoylbis(N,N-diethylaniline) hydrochloride (C.I. Basic Yellow 37) is 22.33 L/kg wet-wt which does not exceed the bioconcentration threshold of 2000.Thus it is concluded that chemical 4,4'-carbonimidoylbis(N,N-diethylaniline) hydrochloride (C.I. Basic Yellow 37) is not expected to bio accumulate in the food chain

Adsorption / desorption:

The Adsorption Coefficient of test substance 4,4'-carbonimidoylbis[N,N-diethylaniline] monohydrochloride (CAS No. 6358-36-7) was determined as per the HPLC method (OECD Guideline-121). The Log Koc value was found to be 1.809 ± 0.001 at 25°C.

Additional information

Hydrolysis:

Predicted data for the test substance4,4'-carbonimidoylbis[N,N-diethylaniline] monohydrochloride and its structurally related substance were reviewed for hydrolysis endpoint and are presented below as weight of evidence approach:

Hydrolysis of4,4'-carbonimidoylbis[N,N-diethylaniline] monohydrochloridewas predicted using OECD QSAR toolbox version 3.3 (2017). The

hydrolytic half-life of 4,4'-carbonimidoylbis[N,N-diethylaniline] monohydrochloride was estimated to be 156.41 days. This value indicates that

4,4'-carbonimidoylbis[N,N-diethylaniline] monohydrochloride very negligibly hydrolysable.

The hydrolysis rate conatant of structuralyy related chemical 4-[(4-dimethylaminophenyl)-phenylmethylidene]cyclohexa-2,5-dien-1-ylidene]-dimethylazanium chloride (CAS 569 -64 -2) 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 hyrolysis.

Considering the above summarised data and by applying weight of evidence approach it can be concluded that the substance

4,4'-carbonimidoylbis[N,N-diethylaniline] monohydrochloride is very negligibly/ slowly hydrolysable.

Biodegradation in water

35-days Closed Bottle test following the OECD guideline 301D to determine the ready biodegradability of the test item 4,4'-carbonimidoylbis[N,Ndiethylaniline] monohydrochloride, CAS No. 6358-36-7. The test system included control, test item and reference item. The concentration of test and reference item ( Sodium Benzoate) chosen for both the study was 4 mg/L, while that of inoculum was 32 ml/l. ThOD (Theoretical oxygen demand) of test and reference item was determined by calculation. % Degradation was calculated using the values of BOD and ThOD for test item and reference item. The BOD35 value of 4,4'-carbonimidoylbis[N,N-diethylaniline] monohydrochloride, CAS No. 6358-36-7 was observed to be 0.52 mgO2/mg. ThOD was calculated as 2.31 mgO2/mg. Accordingly, the % degradation of the test item after 35 days of incubation at 20 ± 1°C according to Closed Bottle test was found to be 22.51%. Based on the results, the test item, under the test conditions, was considered to be primary inherent biodegradable.

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 C.I. Basic Yellow 37 (CAS No. 6358 -36 -7). If released in to the environment, 4.28% of the chemical will partition into water according to the Mackay fugacity model level III and the half-life period of C.I. Basic Yellow 37 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 C.I. Basic Yellow 37 in sediment is estimated to be 541.66 days (13000 hrs). Based on this half-life, it indicates that the chemical C.I. Basic Yellow 37 is persistent in sediment.   

Biodegradation in soil

The half-life period of C.I. Basic Yellow 37 (CAS No. 6358 -36 -7) 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, 62.8% of the chemical will partition into soil according to the Mackay fugacity model level III. The half-life period of C.I. Basic Yellow 37 in soil is estimated to be 120 days (2880 hrs). Based on this half-life value of C.I. Basic Yellow 37, 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: aquatic / sediment:

Five studies including predicted data from validated models and experimental result of Bioaccumulation endpoint for the target chemical C.I. Basic Yellow 37 (Cas no. 6358-36-7) and its structurally similar read across chemical were reviewed to summarize as follows:  

 

First study from prediction model EPI suite 2017 using BCFBAF Program (v3.01), the estimated bio concentration factor (BCF) for target chemical C.I. Basic Yellow 37 is 22.33 L/kg wet-wt.

 

Similarly another prediction model PBT profiler; 2017 indicated that the Bioaccumulation factor (BCF) was predicted to be 22 L/kg wet-wt at 25 deg.C for C.I. Basic Yellow 37.

 

From J-check database;2017 for read across Cas no. 509-34-2 experimental study result suggest that Bioaccumulation test was conducted for 28 days for determination the bioconcentration factor (BCF) and lipid content of test substance 3',6'Bis(diethylamino)spiro[isobenzofuran1(3H),9'[9H]xanthene]3one (Cas no.509-34-2) on test organism Cyprinus carpio.The purity of test substance by HPLC and LCMS was found to be 99.6% and water solubility value is 851mg/l at 25ᵒC .The recovery ratio is given-Test water: 97.8 % and Fish: 91.9 %  And Nominal concentrations used in the study as - 1st concentration area: 10 microg/L, 2nd concentration area: 1 microg/L and Range finding study was carried out on Rice fish (Oryzias latipes) and the 96 hr LC50 value was found to be > 10.0 mg/L.

By analytical methods, the limit of quantification was found to be-

Test water: (Fish: 9.3 ng/g)

1st concentration area: 0.18 µg/l

2nd concentration area: 0.018µg/l 

Whereas the lipid content at the start and end of exposure was found to be 2.87% and 1.94%, respectively. Thus according to guideline OECD Guideline 305 (Bioconcentration: Flow through Fish Test) the BCF value for test substance 3',6'Bis(diethylamino)spiro[isobenzofuran1(3H),9'[9H]xanthene]3one (Cas no.509-34-2) was observed to be <= 0.91 L/kg at dose concentration 10 microg/L and <= 9.1 L/kg at dose concentration 1 microg/L on test organism Cyprinus carpio during 28 day period. These values indicate that the substance is not bioaccumulative.

 

Other experimental result (CHRIP National Institute of Technology and Evaluation , 2017) for read across chemical Rhodamine B (Cas no.81-88-9) indicate Bioaccumulation study was conducted in cyprinus carpio for 6 weeks and the BCF was found to be 0.2 and 1.7 L/Kg at the concentrations of 100 and 10 microgram /l for test substance Rhodamine B.

 

Last study from HSDB database; 2017 for read across chemical auramine hydrochloride (Cas no. 2465-27-2) indicated the BCF range for auramine hydrochloride was experimentally determined to be 3.8-16 in a flow-through test using carp, Cyprinus Carpio This BCF value indicates that auramine hydrochloride will not bioconcentrate in fish.

 

Thus based on the above all available studies for target as well as read-across substance, it is concluded that the test substance chemical C.I. Basic Yellow 37 (Cas no. 6358-36-7) is non Bioaccumulative in aquatic environment.

Adsorption / desorption:

The adsorption coefficient Koc in soil and in sewage sludge 4,4'-carbonimidoylbis[N,N-diethylaniline] monohydrochloride(CAS No.6358-36-7) was determined by the Reverse Phase High Performance Liquid Chromatographic method according to OECD Guideline No. 121 for testing of Chemicals. The reference

substances were chosen according to functional similarity with the test substance and calibration graph prepared. The reference substances were N-methylaniline, 2 - nitrophenol, Nitrobenzene, 4-Nitrobenzamide, N,N-dimethylbenzamide, N-methylbenzamide, Benzamide having Koc value ranging from 1.239 to 2.47 The Log Koc value was found to be 1.809 ± 0.001at 25°C.

This value indicates that the test substance has low sorption to soil and sediment, moderate migration to ground water.