Hydrogen [4-[4-(dimethylamino)-α-(2-hydroxy-3,6-disulphonato-1-naphthyl)benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium, monosodium salt

Endpoint summary

Description of key information

Biodegradation in water

Biodegradability of Hydrogen [4-[4-(dimethylamino)-α-(2 -hydroxy-3,6 -disulphonato-1 -naphthyl)benzylidene]cyclohexa-2,5 -dien-1 -ylidene]dimethylammonium, monosodium salt (CAS no. 3087 -16 -9) is predicted using QSAR toolbox version 3.3 with logKow as the primary descriptor (2017). Test substance undergoes 1.86% degradation by BOD in 28 days. Thus, based on percentage degradation, the test chemical Hydrogen [4 -[4 -(dimethylamino)-α-(2 -hydroxy-3,6 -disulphonato-1 -naphthyl)benzylidene]cyclohexa-2,5 -dien-1 -ylidene]dimethylammonium, monosodium salt 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 Hydrogen [4 -[4 -(dimethylamino)-α-(2 -hydroxy-3,6 -disulphonato-1 -naphthyl)benzylidene]cyclohexa-2,5 -dien-1 -ylidene]dimethylammonium, monosodium salt (CAS No. 3087 -16 -9). If released in to the environment, 1.43% of the chemical will partition into water according to the Mackay fugacity model level III and the half-life period of Hydrogen [4 -[4 -(dimethylamino)-α-(2 -hydroxy-3,6 -disulphonato-1 -naphthyl)benzylidene]cyclohexa-2,5 -dien-1 -ylidene]dimethylammonium, monosodium salt 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 Hydrogen [4 -[4 -(dimethylamino)-α-(2 -hydroxy-3,6 -disulphonato-1 -naphthyl)benzylidene]cyclohexa-2,5 -dien-1 -ylidene]dimethylammonium, monosodium salt in sediment is estimated to be 541.66 days (13000 hrs). Based on this half-life value, it indicates that Hydrogen [4 -[4 -(dimethylamino)-α-(2 -hydroxy-3,6 -disulphonato-1 -naphthyl)benzylidene]cyclohexa-2,5 -dien-1 -ylidene]dimethylammonium, monosodium salt is persistent in sediment.

Biodegradation in soil

The half-life period of Hydrogen [4 -[4 -(dimethylamino)-α-(2 -hydroxy-3,6 -disulphonato-1 -naphthyl)benzylidene]cyclohexa-2,5 -dien-1 -ylidene]dimethylammonium, monosodium salt (CAS No. 3087 -16 -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, 29.9% of the chemical will partition into soil according to the Mackay fugacity model level III. The half-life period of Hydrogen [4 -[4 -(dimethylamino)-α-(2 -hydroxy-3,6 -disulphonato-1 -naphthyl)benzylidene]cyclohexa-2,5 -dien-1 -ylidene]dimethylammonium, monosodium salt in soil is estimated to be 120 days (2880 hrs). Based on this half-life value of Hydrogen [4 -[4 -(dimethylamino)-α-(2 -hydroxy-3,6 -disulphonato-1 -naphthyl)benzylidene]cyclohexa-2,5 -dien-1 -ylidene]dimethylammonium, monosodium salt, 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

From BCFBAF Program (v3.00) model of EPI suite and PBT profiler the estimated bio concentration factor (BCF) for Hydrogen [4-[4-(dimethylamino)-α-(2-hydroxy-3,6-disulphonato-1-naphthyl)benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium, monosodium salt is 3.2 L/kg wet-wt which does not exceed the bioconcentration threshold of 2000.Thus it is concluded that Hydrogen [4-[4-(dimethylamino)-α-(2-hydroxy-3,6-disulphonato-1-naphthyl)benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium, monosodium salt  is not expected to bio accumulate in the aquatic environment.

Adsorption / desorption

The Adsorption Coefficient of test substance Hydrogen [4-[4-(dimethylamino)-α-(2-hydroxy-3,6-disulphonato-1-naphthyl)benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium, monosodium salt (CAS No. 3087-16-9)was determined as per the HPLC method (OECD Guideline-121). The Log Koc value was found to be 0.269 ± 0.0 at at 25°C.

Additional information

Biodegradation in water

1 predicted data for the target compound Hydrogen [4-[4-(dimethylamino)-α-(2-hydroxy-3,6-disulphonato-1-naphthyl)benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium, monosodium salt(CAS no. 3087-16-9) and the total 3 weight of evidence studies (from authoritative database) 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 QSAR toolbox version 3.3 with logKow as the primary descriptor, percentage biodegradability of test chemical Hydrogen [4-[4-(dimethylamino)-α-(2-hydroxy-3,6-disulphonato-1-naphthyl)benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium, monosodium salt(CAS no. 3087-16-9) was estimated. Test substance undergoes 1.86% degradation by BOD in 28 days. Thus, based on percentage degradation, the test chemical Hydrogen [4 -[4 -(dimethylamino)-α-(2 -hydroxy-3,6 -disulphonato-1 -naphthyl)benzylidene]cyclohexa-2,5 -dien-1 -ylidene]dimethylammonium, monosodium salt was estimated to be not readily biodegradable in water.

 

In a weight of evidence study from authoritative database (J-CHECK, 2016) for 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(CAS no. 1694-09-3),biodegradation experiment was conducted for 28 days. 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 read across substance was determined to be 1, 4 and 0% by BOD, TOC removal and HPLC parameter in 28 days. Thus, based on percentage degradation, sodium 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.

 

Another supporting weight of evidence study of biodegradation 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 (CAS no. 3520 -42 -1) (J-CHECK). 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 read across 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 an additional studyof read acrosssubstance2'-anilino-6'-[cyclohexyl(methyl)amino]-3'-methyl-3H-spiro[2 -benzofuran-1,9'-xanthen]-3 -one (CAS no. 55250 -84 -5) from authoritative database (J-CHECK, 2016),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 test substance was determined to be 0% by BOD and HPLC parameter in 28 days. Thus, based on percentage degradation, 2'-anilino-6'-[cyclohexyl(methyl)amino]-3'-methyl-3H-spiro[2 -benzofuran-1,9'-xanthen]-3 -one is considered to be not readily biodegradable in nature.

 

On the basis of above results for target chemicalHydrogen [4-[4-(dimethylamino)-α-(2-hydroxy-3,6-disulphonato-1-naphthyl)benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium, monosodium salt(from OECD QSAR toolbox version 3.3) and for its read across substance (from authoritative database J-CHECK), it can be concluded that the test substance 4Hydrogen [4-[4-(dimethylamino)-α-(2-hydroxy-3,6-disulphonato-1-naphthyl)benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium, monosodium saltcan 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 Hydrogen [4 -[4 -(dimethylamino)-α-(2 -hydroxy-3,6 -disulphonato-1 -naphthyl)benzylidene]cyclohexa-2,5 -dien-1 -ylidene]dimethylammonium, monosodium salt (CAS No. 3087 -16 -9). If released in to the environment, 1.43% of the chemical will partition into water according to the Mackay fugacity model level III and the half-life period of Hydrogen [4 -[4 -(dimethylamino)-α-(2 -hydroxy-3,6 -disulphonato-1 -naphthyl)benzylidene]cyclohexa-2,5 -dien-1 -ylidene]dimethylammonium, monosodium salt 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 Hydrogen [4 -[4 -(dimethylamino)-α-(2 -hydroxy-3,6 -disulphonato-1 -naphthyl)benzylidene]cyclohexa-2,5 -dien-1 -ylidene]dimethylammonium, monosodium salt in sediment is estimated to be 541.66 days (13000 hrs). Based on this half-life value, it indicates that Hydrogen [4 -[4 -(dimethylamino)-α-(2 -hydroxy-3,6 -disulphonato-1 -naphthyl)benzylidene]cyclohexa-2,5 -dien-1 -ylidene]dimethylammonium, monosodium salt is persistent in sediment.

Biodegradation in soil

The half-life period of Hydrogen [4 -[4 -(dimethylamino)-α-(2 -hydroxy-3,6 -disulphonato-1 -naphthyl)benzylidene]cyclohexa-2,5 -dien-1 -ylidene]dimethylammonium, monosodium salt (CAS No. 3087 -16 -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, 29.9% of the chemical will partition into soil according to the Mackay fugacity model level III. The half-life period of Hydrogen [4 -[4 -(dimethylamino)-α-(2 -hydroxy-3,6 -disulphonato-1 -naphthyl)benzylidene]cyclohexa-2,5 -dien-1 -ylidene]dimethylammonium, monosodium salt in soil is estimated to be 120 days (2880 hrs). Based on this half-life value of Hydrogen [4 -[4 -(dimethylamino)-α-(2 -hydroxy-3,6 -disulphonato-1 -naphthyl)benzylidene]cyclohexa-2,5 -dien-1 -ylidene]dimethylammonium, monosodium salt, 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 Hydrogen [4-[4-(dimethylamino)-α-(2-hydroxy-3,6-disulphonato-1-naphthyl)benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium, monosodium salt can be considered to be not readily biodegradable in nature.

Bioaccumulation: aquatic / sediment

Three studies including predicted result from validated model and experimental data from authorative database for bioaccumulation endpoint of test chemical Hydrogen [4-[4-(dimethylamino)-α-(2-hydroxy-3,6-disulphonato-1-naphthyl)benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium, monosodium salt (Cas no. 3087-16-9) with relevant read across which is structurally similar to target were reviewed as follows:

First prediction report indicate from BCFBAF Program (v3.00) model of EPI suite and PBT profiler the estimated bio concentration factor (BCF) for Hydrogen [4-[4-(dimethylamino)-α-(2-hydroxy-3,6-disulphonato-1-naphthyl)benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium, monosodium salt is 3.2 L/kg wet-wt which does not exceed the bioconcentration threshold of 2000.Thus Hydrogen [4-[4-(dimethylamino)-α-(2-hydroxy-3,6-disulphonato-1-naphthyl)benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium, monosodium salt not consider to bio accumulate in the aquatic environment.

Above estimated result of target supported by read across chemical malachite green(N-(4-{[4-(dimethylamino)phenyl](phenyl)methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride –Cas no. 569-64-2), indicates from authorative database HSDB an estimated BCF of 3 was calculated for malachite green(N-(4-{[4-(dimethylamino)phenyl](phenyl)methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride), using a log Kow of 0.62 and a regression derived equation.This BCF suggests the potential for bioconcentration in aquatic organisms is low.

One another read across chemical gentian violet (N-(4-{bis[4-(dimethylamino)phenyl]methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride -Cas no.548-62-9) from same data source i.e HSDB database also assist to above both results as BCF of 3 observed using a log Kow of 0.51 and a regression derived equation. This BCF suggests the potential for bioconcentration in aquatic organisms is low.

From all studies BCF value observed in the range of 3-3.2 (L/Kg or dimensionless) which gives the common conclusion as test chemical Hydrogen [4-[4-(dimethylamino)-α-(2-hydroxy-3,6-disulphonato-1-naphthyl)benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium, monosodium salt (Cas no. 3087-16-9) is non bio accumulative in the aquatic environment.

Adsorption / desorption

The adsorption coefficient Koc in soil and in sewage sludge Hydrogen [4-[4-(dimethylamino)-α-(2-hydroxy-3,6-disulphonato-1-naphthyl)benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium,monosodium salt(CAS No.3087-16-9) 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 group similarity with the test substance and calibration graph prepared. The reference substances were xylene, ethylbenzene, toluene, naphthalene and phenol having Koc value ranging from 1.32 to 2.75. The Log Koc value was found to be 0.269 ± 0.0 at 25°C.