Sodium 4-(4-(2-hydroxynaphthalenylazo)phenylazo)benzenesulphonate

Endpoint summary

Description of key information

Biodegradation in water:

Percent biodegradation of test chemical Sodium 4-(4-(2-hydroxynaphthalenylazo)phenylazo) benzenesulphonate was observed to be  9.0 %  and 15 % in low spike  that is 1 mg/mL concentration  and high spike that is 5 mg/L concentration of test chemical by  considering test material analysis by HPLC  as parameter.  On the basis of percent degradation it is concluded that this test material is not readily biodegradable.

Biodegradation 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 sodium 4-({4-[(2-hydroxy-1-naphthyl)diazenyl]phenyl}diazenyl)benzenesulfonate (CAS No.6406 -56 -0). If released in to the environment, 5.57 % of the chemical will partition into water according to the Mackay fugacity model level III and the half-life period of test chemical sodium 4-({4-[(2-hydroxy-1-naphthyl)diazenyl]phenyl}diazenyl)benzenesulfonate in water is estimated to be 60.0 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 test chemical sodium 4-({4-[(2-hydroxy-1-naphthyl)diazenyl]phenyl}diazenyl)benzenesulfonate in sediment is estimated to be 541.6 days (13000  hrs). Based on this half-life value, it indicates that test chemical sodium 4-({4-[(2-hydroxy-1-naphthyl)diazenyl]phenyl}diazenyl)benzenesulfonate is persistent in sediment.

Biodegradation in Soil:

The half-life period of test chemical sodium 4-({4-[(2-hydroxy-1-naphthyl)diazenyl]phenyl}diazenyl)benzenesulfonate(CAS No. 6406 -56 -0) 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, 57.6 % of the chemical will partition into soil according to the Mackay fugacity model level III. The half-life period of test chemical sodium 4-({4-[(2-hydroxy-1-naphthyl)diazenyl]phenyl}diazenyl)benzenesulfonate in soil is estimated to be 120 days (2800 hrs). Based on this half-life value of test chemical sodium 4-({4-[(2-hydroxy-1-naphthyl)diazenyl]phenyl}diazenyl)benzenesulfonate, 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:

 Experimental studies from different sources and one predicted data have been conducted for target chemical Sodium 4-(4-(2-hydroxynaphthalenylazo)phenylazo) benzenesulphonate (Acid Red 151) CAS no. 6406-56-0 and one experimental studies also conducted for its read across chemical results af all studies are summarized below for biodegradation in water endpoint.

 

The first experimental study have been conducted from Chemosphere Vol 22 pp 107-119 1991 by Glenn M Shaul, Thomas J Holdsworth, Clyde R. Dempsey, and Kenneth A. Dostal in this study the biodegradability of test chemical Sodium 4-(4-(2-hydroxynaphthalenylazo)phenylazo) benzenesulphonate (Acid Red 151) was determined by analyzing percent recovery of test material. This test material is dye and inoculums used for biodegradation was obtained from Screened raw waste water from greater Cincinnati Mill Creek sewage treatment plant was used as influent (INF) to three pilot scale activated sludge biological treatment systems (Two experimental and one control). Each system consists of primary clarifier, complete mix aeration basin and secondary clarifier. Influent was spiked with test material at concentration of 1 mg/L and 5 mg/L. Then Dye analytical studies were conducted by purified dye compound in organic free influent waste water and mixed liquor. Then influent, primary influent filtrate was passed through column packed with resin. The filter paper and resin were soaked in an ammonia – acetonitrile solution and then soxhlet extracted with ammonia – acetonitrile. The extract was concentrated and brought upto 50 ml volumn with methanol/dimethyl formamaide solution. All extracted samples were analyzed by HPLC with ultraviolet detector.

Percent recovery and Percent adsorbed of test chemical Sodium 4-(4-(2-hydroxynaphthalenylazo)phenylazo)benzenesulphonatewas observed was 82% and 50 % in low spike of test chemical and 70 % and 58% at high spike of test chemical respectively. On the basis of percent recovery value biodegradation of dye was 9.0 % at low spike and 15 % at high spike of test chemical. On the basis of percent degradation it is concluded that this test material is not readily biodegradable.

 

 

 Next experimental study was done from Bioresource Technology 92 (2004) 143–149 by German Buitron , Maribel Quezada, Gloria Moreno in this study an experiment was conducted to determined biodegradation efficiency of test chemical Acid red 151. The system consisted in an aerated SBB made of acrylic with a total volume of 9.8 l, of which 6 l were working volume (liquid). The packing material (3.8 l) was a porous volcanic rock (puzolane) with a diameter from 2.0 to 2.5 cm. Each cycle of the SBB consisted of four periods controlled by a timer: fill and draw (3 and 13 min, respectively), reaction (variable) and settle (30 min). The exchange rate in each cycle was 75% of the total volume. The temperature was maintained at 25oC. Activated sludge from a municipal wastewater treatment plant was used as inoculum (2500 mg/l as volatile suspended solids, VSS). The pH was maintained at approximately 7 and mineral salts were added according to AFNOR (1985). The operation of the SBB was followed during 667 days. Two initial concentrations were used (25 and 50 mg AR 151/l) as a sole source of carbon and energy. Reaction times of 24, 12, 8 and 4 h were tested. For each concentration, the reaction time was varied to acclimate the microorganisms. Thus, the reaction time was maintained for 24 h until a constant degradation rate, qv, was observed. Then , the reaction times were reduced to 12, 8 and 4 h. Final AR151 concentration, obtained when 70% or more of the initial Acid Red 151 was removed from the system, mg/l. A maximal biodegradation efficiency of 99% was obtained when the reactor was fed with a concentration of 25 mg AR151/l and 12 h of cycle. The biodegradation efficiencies varied between 60% and 99% with an average value of 88%. A maximal degradation rate of 247 mg AR151/(lreactor d) was obtained. On the basis of this degradation rate of Acid Red 151 it is concluded that Acid red 151 is degradable in specific conditions with acclimated organisms this degradation efficiency was also due to adsorption of Acid red 151.

 

 One more experimental study was done from Rasayan journal Vol.3, No.4 (2010), 731-735 by Praveen Sharma, Lakhvinder Singh and Jyoti Mehta in this study an experiment was conducted to determine biodegradability of test chemical sodium 4-({4-[(2-hydroxy-1-naphthyl)diazenyl]phenyl}diazenyl)benzenesulfonate for this experiment the bacterial strains were isolated from dye-contaminated soil collected from within the premises of a textile industry the isolated bacteria were identified as Bacillus subtilis and Achromobacter xyloxidans bacteria. Stock solution of test chemical was prepared at 1000 mg/L concentration then it was diluted to desired concentration and inoculated with isolated bacteria then Erlenmeyer flask were incubated for 7 days then the COD of the samples was determined by standard dichromate reflux method. The percent COD removal of test chemical sodium 4-({4-[(2-hydroxy-1-naphthyl)diazenyl]phenyl}diazenyl)benzenesulfonate was determined to be 81 percent in 7days. On the basis of this COD removal value it is conclude that this test chemical is readily biodegradable.

 

 Next study was predicted data study in this study the Biodegradability of test chemical Sodium 4-(4-(2-hydroxynaphthalenylazo)phenylazo)benzenesulphonate (CAS no. 6406 -56 -0) was predicted by using OECD QSAR tool box v3.4 considering six closest read across chemicals with log Kow as primary descriptor. The percent biodegradability of test chemical Sodium 4-(4-(2-hydroxynaphthalenylazo)phenylazo)benzenesulphonate was determined to 2.33% by considering BOD as parameter and microorganisms as inoculum in 28 days. On the basis of percent biodegradability value it is concluded that test chemical Sodium 4-(4-(2-hydroxynaphthalenylazo)phenylazo)benzenesulphonate is not readily biodegradable.

 

 Last study was also experimental study done for structurally similar read across chemical done fromauthoritative data base (HSDB, 2017) in this study the read across chemical disodium 6-hydroxy-5-[(4-sulfonatophenyl)diazenyl]naphthalene-2-sulfonate (CAS no. 2783-94-0) showed 0.0% biodegradation by considering BOD as parameter in 5 days, and by taking sewage as inoculums. So it is concluded that test chemical disodium 6-hydroxy-5-[(4-sulfonatophenyl)diazenyl]naphthalene-2-sulfonate is not readily biodegradable.

 

 By considering results of all the studies mentioned above it was observed that in first experimental study target chemical showed very less percent biodegradability and in another study it showed very high value of efficiency of biodegradation in specific conditions and duration of study was also not mentioned properly so from this study it is clear that target chemical sodium 4-({4-[(2-hydroxy-1-naphthyl)diazenyl]phenyl}diazenyl)benzenesulfonate is biodegradable but not readily in third experimental study target chemical have shown 81 % biodegradation in 7 days according to this results target chemical can be considered as readily biodegradable but organisms used in this study were specifically isolated for degradation of target chemical and they are Bacillus subtilis and Achromobacter xyloxidans these two bacteria got acclimated to target chemical and these are resistant to dyes. Next study was prediction for target chemical it showed very less biodegradability and to corroborate this results structurally similar read across chemical of target chemical also showed very less biodegradability. On the basis of all the results it is concluded that target chemical is not readily biodegradable.

Biodegradation 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 sodium 4-({4-[(2-hydroxy-1-naphthyl)diazenyl]phenyl}diazenyl)benzenesulfonate (CAS No.6406 -56 -0). If released in to the environment, 5.57 % of the chemical will partition into water according to the Mackay fugacity model level III and the half-life period of test chemical sodium 4-({4-[(2-hydroxy-1-naphthyl)diazenyl]phenyl}diazenyl)benzenesulfonate in water is estimated to be 60.0 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 test chemical sodium 4-({4-[(2-hydroxy-1-naphthyl)diazenyl]phenyl}diazenyl)benzenesulfonate in sediment is estimated to be 541.6 days (13000  hrs). Based on this half-life value, it indicates that test chemical sodium 4-({4-[(2-hydroxy-1-naphthyl)diazenyl]phenyl}diazenyl)benzenesulfonate is persistent in sediment.

Biodegradation in Soil:

The half-life period of test chemical sodium 4-({4-[(2-hydroxy-1-naphthyl)diazenyl]phenyl}diazenyl)benzenesulfonate(CAS No. 6406 -56 -0) 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, 57.6 % of the chemical will partition into soil according to the Mackay fugacity model level III. The half-life period of test chemical sodium 4-({4-[(2-hydroxy-1-naphthyl)diazenyl]phenyl}diazenyl)benzenesulfonate in soil is estimated to be 120 days (2800 hrs). Based on this half-life value of test chemical sodium 4-({4-[(2-hydroxy-1-naphthyl)diazenyl]phenyl}diazenyl)benzenesulfonate, 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.