m-(4,5-dihydro-5-imino-3-methyl-1H-pyrazol-1-yl)benzenesulphonic acid

Endpoint summary

Description of key information

Biodegradation in water:

Biodegradability of test chemical 3-(5-imino-3-methyl-4,5-dihydro-1H-pyrazol-1-yl)benzene-1-sulfonic acid (CAS no. 68083 -38 -5) was estimated by using OECD QSAR tool box v3.3 by considering five closest read across chemicals with log Kow as primary descriptor. Percent degradation of test chemical 3-(5-imino-3-methyl-4,5-dihydro-1H-pyrazol-1-yl)benzene-1-sulfonic acid was determined to be 0.0% by considering BOD as parameter and microorganisms as inoculum in 28 days. On the basis of percent biodegradability it is concluded that test chemical 3-(5-imino-3-methyl-4,5-dihydro-1H-pyrazol-1-yl)benzene-1-sulfonic acid 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 m-(4,5-dihydro-5-imino-3-methyl-1H-pyrazol-1-yl)benzenesulphonic acid (CAS No. 68083 -38 -5). If released in to the environment, 19.6 % 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 15 days (360 hrs). The half-life (15 days 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 m-(4,5-dihydro-5-imino-3-methyl-1H-pyrazol-1-yl)benzenesulphonic acid in sediment is estimated to be 135 days (3240 hrs). However, as the percentage release of test chemical into the sediment is less than 1 % (i.e, reported as 0.109 %), indicates that test chemical m-(4,5-dihydro-5-imino-3-methyl-1H-pyrazol-1-yl)benzenesulphonic acid is not persistent in sediment.

Biodegradation in soil:

The half-life period of test chemical m-(4,5-dihydro-5-imino-3-methyl-1H-pyrazol-1-yl)benzenesulphonic acid (CAS No. 68083 -38 -5) 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, 80.3 % of the chemical will partition into soil according to the Mackay fugacity model level III. The half-life period of test chemical m-(4,5-dihydro-5-imino-3-methyl-1H-pyrazol-1-yl)benzenesulphonic acid in soil is estimated to be 30 days (720 hrs). Based on this half-life value of test chemical m-(4,5-dihydro-5-imino-3-methyl-1H-pyrazol-1-yl)benzenesulphonic 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:

Predicted data for the target compound 3-(5-imino-3-methyl-4,5-dihydro-1H-pyrazol-1-yl)benzene-1-sulfonic acid (CAS no. 68083 -38 -5)and supporting weight of evidence studies for its structurally similar read across substance were reviewed for the biodegradation end point which are summarized as below:

In first weight o f evidence study the biodegradability of test chemical 3-(5-imino-3-methyl-4,5-dihydro-1H-pyrazol-1-yl)benzene-1-sulfonic acid (CAS no. 68083 -38 -5) was estimated by using OECD QSAR tool box v3.3 by considering five closest read across chemicals with log Kow as primary descriptor. Percent degradation of test chemical 3-(5-imino-3-methyl-4,5-dihydro-1H-pyrazol-1-yl)benzene-1-sulfonic acid was determined to be 0.0% by considering BOD as parameter and microorganisms as inoculum in 28 days. On the basis of percent biodegradability it is concluded that test chemical 3-(5-imino-3-methyl-4,5-dihydro-1H-pyrazol-1-yl)benzene-1-sulfonic acid is not readily biodegradable.

 

Next predicted data study was done by using the Estimation Programs Interface Suite (EPI suite, 2017) to estimated the biodegradation potential of the test compound m-(4,5-dihydro-5-imino-3-methyl-1H-pyrazol-1-yl)benzenesulphonic acid (CAS no. 68083 -38 -5) 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 Biowin 1-7, respectively) of the BIOWIN v4.10 software. The results indicate that chemical  m-(4,5-dihydro-5-imino-3-methyl-1H-pyrazol-1-yl)benzenesulphonic acid is expected to be not readily biodegradable.

 

Another study was experimental study done from authoritative database (J CHECK, 2017) in this study the biodegradation experiment was conducted for 28 days for evaluating the percentage biodegradability of read across substance 3 -aminobenzenesulfonic acid (CAS no. 121 -47 -1). Concentration of inoculum i.e, sludge used was 30 mg/l and initial test substance conc. used in the study was 100 mg/l. The percentage degradation of read across substance 3 -aminobenzene sulfonic acid was determined to be 1.1 and <0% by BOD, O2 consumption, TOC removal, test material analysis and UV-Vis parameter in 28 days. Thus, based on percentage degradation, 3 -aminobenzenesulfonic acid is considered to be not readily biodegradable in nature.

 

Last study was also experimental study done from same source as mentioned above (J CHECK, 2017) in this study the Biodegradation experiment was conducted for 28 days for evaluating the percentage biodegradability of read across substance Sulfanilic acid. Concentration of inoculum i.e, sludge used was 100 mg/l and initial test substance conc. used in the study was 30 mg/l. The percentage degradation of read across substance was determined to be 3% by BOD, 4% by TOC removal and 1% by HPLC in 28 days. Thus, the substance Sulfanilic acid is not expected to be readily biodegradable in water.

 

On the basis of results of above mentioned studies for target chemical 3-(5-imino-3-methyl-4,5-dihydro-1H-pyrazol-1-yl)benzene-1-sulfonic acid (CAS no. 68083 -38 -5)( from OECD QSAR tool boxv3.3 and EPI suite) and supporting weight of evidence study ( from J Check, 2017). It is concluded that the test chemical 3-(5-imino-3-methyl-4,5-dihydro-1H-pyrazol-1-yl)benzene-1-sulfonic acid can be expected to be 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 m-(4,5-dihydro-5-imino-3-methyl-1H-pyrazol-1-yl)benzenesulphonic acid (CAS No. 68083 -38 -5). If released in to the environment, 19.6 % 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 15 days (360 hrs). The half-life (15 days 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 m-(4,5-dihydro-5-imino-3-methyl-1H-pyrazol-1-yl)benzenesulphonic acid in sediment is estimated to be 135 days (3240 hrs). However, as the percentage release of test chemical into the sediment is less than 1 % (i.e, reported as 0.109 %), indicates that test chemical m-(4,5-dihydro-5-imino-3-methyl-1H-pyrazol-1-yl)benzenesulphonic acid is not persistent in sediment.

Biodegradation in soil:

The half-life period of test chemical m-(4,5-dihydro-5-imino-3-methyl-1H-pyrazol-1-yl)benzenesulphonic acid (CAS No. 68083 -38 -5) 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, 80.3 % of the chemical will partition into soil according to the Mackay fugacity model level III. The half-life period of test chemical m-(4,5-dihydro-5-imino-3-methyl-1H-pyrazol-1-yl)benzenesulphonic acid in soil is estimated to be 30 days (720 hrs). Based on this half-life value of test chemical m-(4,5-dihydro-5-imino-3-methyl-1H-pyrazol-1-yl)benzenesulphonic acid, it is concluded that the chemical is not persistent in the soil environment and the exposure risk to soil dwelling animals is low .