4-[(3-aminobenzoyl)amino]-5-hydroxynaphthalene-1,7-disulphonic acid

Endpoint summary

Description of key information

Biodegradation in water:

Biodegradability of test chemical 4-[(3-aminobenzoyl)amino]-5-hydroxynaphthalene-1,7-disulphonic acid was estimated by using OECD QSAR tool box v3.3 and using five closest read across chemical with log Kow as primary descriptor. Percent biodegradability of test chemical 4-[(3-aminobenzoyl)amino]-5-hydroxynaphthalene-1,7-disulphonic acid was  determined to be 2.43% by considering BOD as parameter  and microorganisms as inoculum in 28 days. Based on percent biodegrdability value it can be concluded that this test chemical is not readily 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 4-[(3-aminobenzoyl)amino]-5-hydroxynaphthalene-1,7-disulphonic acid (CAS no.70239 -77 -9) . If released in to the environment, 11.3 % of the chemical will partition into water according to the Mackay fugacity model level III and the half-life period of test chemical in water is estimated to be 37.5 days (360 hrs). The half-life (37.5days estimated by EPI suite) indicates that the chemical is not persistent in water and the exposure risk to aquatic animals is low whereas the half-life period of test chemical ) 4-[(3-aminobenzoyl)amino]-5-hydroxynaphthalene-1,7-disulphonic acid in sediment is estimated to be 337.5 days (8100 hrs). However, as the percentage release of test chemical into the sediment is less than 2% (i.e, reported as 1.43 %), indicates that test chemical 4-[(3-aminobenzoyl)amino]-5-hydroxynaphthalene-1,7-disulphonic acid is not persistent in sediment as well.

Biodegradation in soil:

The half-life period of test chemical 4-[(3-aminobenzoyl)amino]-5-hydroxynaphthalene-1,7-disulphonic acid (CAS no.70239 -77 -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, 87.3 % of the chemical will partition into soil according to the Mackay fugacity model level III. The half-life period of test chemical 4-[(3-aminobenzoyl)amino]-5-hydroxynaphthalene-1,7-disulphonic acid in soil is estimated to be 75 days (1800 hrs). Based on this half-life value of test chemical 4-[(3-aminobenzoyl)amino]-5-hydroxynaphthalene-1,7-disulphonic acid , it is concluded that the chemical is not persistent in the soil environment and the exposure risk to soil dwelling animals is low .

Additional information

Biodegradation in water:

Two predicted data studies for target chemical 4-[(3-aminobenzoyl)amino]-5-hydroxynaphthalene-1,7-disulphonic acid (CAS no. 70239 -77 -9) and three experimental studies for its structurally similar read across chemicals are summarized below for biodegradation in water endpoint.

 

In first weight of evidence study the Biodegradability of test chemical 4-[(3-aminobenzoyl)amino]-5-hydroxynaphthalene-1,7-disulphonic acid was estimated by using OECD QSAR tool box v3.3 and using five closest read across chemical with log Kow as primary descriptor. Percent biodegradability of test chemical 4-[(3-aminobenzoyl)amino]-5-hydroxynaphthalene-1,7-disulphonic acid was  determined to be 2.43% by considering BOD as parameter  and microorganisms as inoculum in 28 days. Based on percent biodegrdability value it can be concluded that this test chemical is not readily biodegradable.

 

Another predicted data study was done by using Estimation Programs Interface Suite (EPI suite, 2017) to estimate the biodegradation potential of the test compound 4-[(3-aminobenzoyl)amino]-5-hydroxynaphthalene-1,7-disulphonic acid (CAS no. 70239 -77 -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 chemical  4-[(3-aminobenzoyl)amino]-5-hydroxynaphthalene-1,7-disulphonic acid is expected to be not readily biodegradable.

 

Next weight of evidence study of read across chemical Acid Red 1 was done from Water Engineering Research Laboratory Cincinnati, OH 45268, July 1988 in this study the water soluble dye Acid Red 1 was dosed to the two experimental systems at target active ingredient doses of 1 and 5 mg/L of influent flow. The primary sludge was not sampled. The influent, primary effluent and sludge effluent were filtered and the filtrate was extracted. All the extracted samples were analysed by HPLC with an ultraviolet-visible detector. Total suspended solids (TSS) analyses were also performed on all the samples. All systems were operated for at least three times. All samples were 24 hour composites made up of 6 grab samples collected every 4 hour stored at 4 degrees Celsius. The pH of the influent was 2.0-8.0. The aeration of basin temperature was 21-25 degrees Celsius. Dissolved oxygen was 2-4 mg/L. Hydraulic retention time was 0.28 days. Solids retention time was 2.7 days. The possible removal mechanism for a dye compound in the ASP system includes adsorption, biodegradation, chemical transformation, photodegradation, chemicals photodegrading and air stripping. The recoveries for the 18 dues were generally very good and with relatively low standard deviations. No photodegrading was found in the laboratory study. The authors assumed that adsorption and biodegradation was the only removal mechanisms of the pilot-scale activated sludge system. If a compound was recovered near the target range of 80% to 120% then it was assumed that this compound was not biodegraded. Conversely, if the recovery was less than 20% to 30% then it was assumed that the compound was apparently biodegraded. Lastly, if the compound was recovered near 80 to 120% one investigated the percentage adsorbed data. If amount adsorbed was greater than 30% then it was concluded that such compound was removed by adsorption. Eleven of the 18 azo dyes passed through the pilot scale activated sludge plant untreated and one on these was Acid Red 1. Acid Red 1 was not removed via adsorption. The relatively high sulfonic acid substitution of these dyes may explain why they were unaffected by the sewage treatment process. By speculation, the position of the sulfonic acid functional groups and the molecular weight appeared to limit uptake by microorganisms. Acid Red 1 was based on this study not consider to be readily biodegraded in regular wastewater treatment plants.

 

Further, another experimental weight of evidence study was done from UERL laboratory (2017) in this study a 28-days closed bottle test following the OECD guideline 301D to determine the ready biodegradability of the same read across chemical Acid Red 1 (CAS No.3734 -67 -6) was performed. The test setup included in addition to Acid Red 1 separate bottles with negative control and positive control (reference substance was sodium benzoate). The tested chemical concentration was 32 mg/L. The inoculum concentration was 32 ml/L. The incubation temperature was 20 ± 1°C. The biological oxygen demand (BOD) was after 28 days of incubation with inoculums determined to be 0.475mg O2/mg. The theoretical oxygen demand (ThOD) was calculated to 1.194mg O2/mg. The % degradation of the read across chemical after 28 days of incubation at 20±1°C was calculated to 39.78%. The chemical could based on 40% degradation after 28 days neither be classified as readily degradable (60% degradation threshold in OECD 301 test) nor inherently degradable (approx. 50-55% degradation threshold in OECD 301 test). The chemical was therefore not considered to be biodegradable under the tested conditions.

 

The last experimental weight of evidence study was done by UERL laboratory (2016)of read across chemical disodium 3- [(2,4 -dimethyl-5 -sulphonatophenyl)azo]-4 -hydroxynaphthalene-1 -sulphonate, CAS No. 4548 -53 -2 in this study a 28-days Manometric respirometry testfollowing the OECD guideline 301F to determine the ready biodegradability of the read across chemical disodium 3- [(2,4 -dimethyl-5 -sulphonatophenyl)azo]-4 -hydroxynaphthalene-1 -sulphonate, CAS No. 4548 -53 -2. The test system included control, test item and reference item. The concentration of read across chemical and reference item ( Sodium Benzoate) chosen for both the study was 30 mg/L, while that of inoculum was 10 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 read across chemical and reference item. The BOD28 value of disodium 3-[(2,4-dimethyl-5-sulphonatophenyl)azo]-4-hydroxynaphthalene-1-sulphonate was observed to be mgO2sup>/mg. ThOD was calculated as mgO2/mg. Accordingly, the % degradation of the test item after 28 days of incubation at 20 ± 1°C according to manometric respirometry test was determined to be 12.807 %.Based on the results, the read across, under the test conditions, was considered to be not readily biodegradable at 20± 1°C over a period of 28 days.

 

On the basis of all the studies mentioned above it is concluded that target chemical 4-[(3-aminobenzoyl)amino]-5-hydroxynaphthalene-1,7-disulfonic acid (CAS no.70239-77-9) can be considered as not readily 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 4-[(3-aminobenzoyl)amino]-5-hydroxynaphthalene-1,7-disulphonic acid (CAS no.70239 -77 -9) . If released in to the environment, 11.3 % of the chemical will partition into water according to the Mackay fugacity model level III and the half-life period of test chemical in water is estimated to be 37.5 days (360 hrs). The half-life (37.5days estimated by EPI suite) indicates that the chemical is not persistent in water and the exposure risk to aquatic animals is low whereas the half-life period of test chemical ) 4-[(3-aminobenzoyl)amino]-5-hydroxynaphthalene-1,7-disulphonic acid in sediment is estimated to be 337.5 days (8100 hrs). However, as the percentage release of test chemical into the sediment is less than 2% (i.e, reported as 1.43 %), indicates that test chemical 4-[(3-aminobenzoyl)amino]-5-hydroxynaphthalene-1,7-disulphonic acid is not persistent in sediment as well.

Biodegradation in soil:

The half-life period of test chemical 4-[(3-aminobenzoyl)amino]-5-hydroxynaphthalene-1,7-disulphonic acid (CAS no.70239 -77 -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, 87.3 % of the chemical will partition into soil according to the Mackay fugacity model level III. The half-life period of test chemical 4-[(3-aminobenzoyl)amino]-5-hydroxynaphthalene-1,7-disulphonic acid in soil is estimated to be 75 days (1800 hrs). Based on this half-life value of test chemical 4-[(3-aminobenzoyl)amino]-5-hydroxynaphthalene-1,7-disulphonic acid , it is concluded that the chemical is not persistent in the soil environment and the exposure risk to soil dwelling animals is low .