Hydrogen bis[2-(3-chlorophenyl)-2,4-dihydro-4-[[2-hydroxy-5-mesylphenyl]azo]-5-methyl-3H-pyrazol-3-onato(2-)]chromate(1-)

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Description of key information

Biodegradation in water

Estimation Programs Interface Suite (EPI suite, 2018) was run to predict the biodegradation potential of the test compound  chromium(3+) ion hydrogen bis(1 -(3 -chlorophenyl)-4 -[(E)-2 -(5 -methanesulfonyl-2 -oxidophenyl)diazen -1 -yl]-3 -methyl-1H-pyrazol-5 -olate) (CAS no. 71598 -35 -1) 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 chromium(3+) ion hydrogen bis(1-(3-chlorophenyl)-4-[(E)-2-(5-methanesulfonyl-2-oxidophenyl)diazen -1-yl]-3-methyl-1H-pyrazol-5-olate) is expected to be not readily biodegradable.

Additional information

Biodegradation in water

Predicted data for the target compound chromium(3 +) ion hydrogen bis(1 -(3 -chlorophenyl)-4 -[(E)-2 -(5 -methanesulfonyl-2 -oxidophenyl)diazen -1 -yl]-3 -methyl-1H-pyrazol-5 -olate) (CAS No. 71598 -35 -1) and various supporting weight of evidence studies for its structurally and functionally similar read across substance were reviewed for the biodegradation end point which are summarized as below:

 

In a prediction using the Estimation Programs Interface Suite (EPI suite, 2018), the biodegradation potential of the test compoundchromium(3+) ion hydrogen bis(1-(3-chlorophenyl)-4-[(E)-2-(5-methanesulfonyl-2-oxidophenyl)diazen -1-yl]-3-methyl-1H-pyrazol-5-olate)(CAS No. 71598-35-1) in the presence of mixed populations of environmental microorganisms was estimated.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 chemicalchromium(3+) ion hydrogen bis(1-(3-chlorophenyl)-4-[(E)-2-(5-methanesulfonyl-2-oxidophenyl)diazen -1-yl]-3-methyl-1H-pyrazol-5-olate)is expected to be not readily biodegradable.

 

In a supporting study from peer reviewed journal (D. Brown, et. al; 1987) for the read across chemical Acid yellow 25 (CAS no. 6359-85-9), biodegradation study was carried out to determine the biodegradability rate of the test substance Acid yellow 25 (CAS no. 6359-85-9). Activated sludge was used as an inoculum and the study was performed under anaerobic conditions at a temperature of 35°C for a period of 56 days. Samples of the aqueous phase were analyzed either qualitatively or quantitatively by an appropriate chromatographic method for the presence of certain of the expected aromatic amine metabolites. The percentage degradation of test substance Acid yellow 25 was determined to be 57% by appropriate chromatography method in 56 days. The metabolites identified by the appropriate chromatographic method were 3 -amino-6 -methylbenzene- N-phenylsulphonamid and 4 -amino-3 -methy1 -1 -[4'-sulphophenyl)pyrazolone, respectively. Thus, based on percentage degradation, chemical Acid yellow 25 is considered to be not readily biodegradable in nature.

 

Another biodegradation study was conducted for evaluating the percentage biodegradation of read across chemical Disodium 2,5 -dichloro-4 -(5 -hydroxy-3 -methyl-4 -(sulphophenylazo)pyrazol-1 -yl)benzenesulphonate (CAS no. 6359-98-4) (from peer reviewed journal Glenn M. Shaul, et. al; 1991 and secondary source Glenn M. Shaul, et. al; 1988). The study was carried out in pilot activated sludge process system using several wastewater and mixed liquor at a temperature of 21-25°C and pH range of 7.0-8.0, respectively. Mass balance calculations were made to determine the amount of the dye compound in the waste activated sludge (WAS) and in the activated sludge effluent (ASE). Activated sludge was used as test inoculum for the study. Test chemical conc. used for the study was 1 and 5 mg/l, respectively. Screened raw wastewater from the Greater Cincinnati Mill Creek Sewage Treatment Plant was used as the influent (INF) to three pilot-scale activated sludge biological treatment systems (two experimental and one control) operated in parallel. Each system consisted of a primary clarifier (33 L), complete-mix aeration basin (200 L), and a secondary clarifier (32 L). Each water soluble dye was dosed as commercial product to the screened raw wastewater for the two experimental systems operated in parallel at targeted active ingredient doses of 1 and 5 mg/L of influent flow (low and high spike systems, respectively).All systems were operated for at least three times.All samples were 24 hr composites made up of 6 grab samples collected every 4 hr and stored at 4°C. The possible removal mechanisms for a dye compound in the ASP system include adsorption, biodegradation, chemical transformation, photodegradation, and air stripping. Dye analytical recovery studies were conducted by dosing the purified dye compound into organic-free water, influent wastewater, and mixed liquor. These studies were run in duplicate and each recovery study was repeated at least once to ensure that the dye compound could be extracted. Purified dye standards were analytically prepared from the commercial dye product by repeated recrystallization. The INF, primary effluent (PE), and ASE were filtered, and the filtrate was passed through a 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 up to 50 mL volume with a methanol/dimethylformamide solution. The mixed liquor (ML) samples were separated into two components, the filtrate or soluble (SOL) fraction and the residue (RES) fraction. The SOL fraction was processed similar to the INF, PE, and ASE samples. The RES fraction and the filter paper were processed similar to these samples but the resin adsorption step was omitted. All extracted samples were analyzed by HPLC with an ultraviolet-visible detector. Total suspended solids (TSS) analyses were also performed on the INF, PE, ML, and ASE samples.Percentage recovery of test chemical Disodium 2,5 -dichloro-4 -(5 -hydroxy-3 -methyl-4 -(sulphophenylazo)pyrazol-1 -yl)benzenesulphonate was determined to be 98-101%,thus, it appeared that little or no chemical transformation occurred for test chemical because of contact with the variable wastewater and/or sludge matrix under these conditions. Also it was evaluated that the chemical Disodium 2,5 -dichloro-4 -(5 -hydroxy-3 -methyl-4 -(sulphophenylazo)pyrazol-1 -yl)benzenesulphonate was adsorbed at a level of1 -<1% on the ML solids, indicating that the compound was substantially untreated by the activated sludge process (ASP). Thus, based on %recovery of test chemical, chemical Disodium 2,5 -dichloro-4 -(5 -hydroxy-3 -methyl-4 -(sulphophenylazo)pyrazol-1 -yl)benzenesulphonate was can be considered to be not readily biodegradable in nature.

 

On the basis of above results for target chemical chromium(3+) ion hydrogen bis(1-(3-chlorophenyl)-4-[(E)-2-(5-methanesulfonyl-2-oxidophenyl)diazen -1 -yl]-3 -methyl-1H-pyrazol-5 -olate) (from EPI suite, 2018) and for its read across substance (from peer reviewed journals and secondary source), it can be concluded that the test substance chromium(3 +) ion hydrogen bis(1 -(3 -chlorophenyl)-4 -[(E)-2 -(5 -methanesulfonyl-2 -oxidophenyl)diazen -1 -yl]-3 -methyl-1H-pyrazol-5 -olate) can be expected to be not readily biodegradable in nature.