4-nitro-m-phenylenediamine

Endpoint summary

Description of key information

Biodegradation in water

Biodegradability of 4-nitrobenzene-1,3-diamine (CAS no. 5131 -58 -8) is predicted using QSAR toolbox version 3.4 with logKow as the primary descriptor (2017). Test substance undergoes 0.85% degradation by BOD in 28 days. Thus, based on percentage degradation, the test chemical 4 -nitrobenzene-1,3 -diamine 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

4 -nitrobenzene-1,3 -diamine (CAS No. 5131 -58 -8). If released in to the environment, 21.1% of the chemical will partition into water according to the Mackay fugacity model level III and the half-life period of 4-nitrobenzene-1,3-diamine in water is estimated to be 37.5 days (900 hrs). The half-life (37.5 days estimated by EPI suite) indicates that the chemical is not persistent in water and the exposure risk to aquatic animals is moderate to low whereas the half-life period of 4 -nitrobenzene-1,3 -diamine in sediment is estimated to be 337.5 days (8100 hrs). However, as the percentage release of test chemical 4 -nitrobenzene-1,3 -diamine into the sediment is less than 1% (i.e, reported as 0.0941%), indicates that 4-nitrobenzene-1,3-diamine is not persistent in sediment.

Biodegradation in soil

The half-life period of 4-nitrobenzene-1,3-diamine (CAS No. 5131 -58 -8) 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, 78.8% of the chemical will partition into soil according to the Mackay fugacity model level III. The half-life period of 4-nitrobenzene-1,3-diamine in soil is estimated to be 75 days (1800 hrs). Based on this half-life value of 4 -nitrobenzene-1,3 -diamine, 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

An estimated BCF value of 3 was calculated in fish for 4-nitro-1,3-benzenediamine ,using an estimated log Kow of 0.55 and a regression-derived equation. This BCF value suggests that the potential for bioconcentration in aquatic organisms (fish) is low.

Adsorption / desorption

From authorative database HSDB,the Koc of 4-nitro-1,3-benzenediamine can be estimated to be 85,using a structure estimation method based on molecular connectivity indices.This estimated Koc value suggests that 4-nitro-1,3-benzenediamine is expected to have high mobility in soil.

Additional information

Biodegradation in water

Various predicted data for the target compound 4 -nitrobenzene-1,3 -diamine (CAS No. 5131 -58 -8) and various supporting weight of evidence studies for its closest read across substance were reviewed for the biodegradation end point which are summarized as below:

 

In a prediction done by SSS (2017) using OECD QSAR toolbox version 3.4 with logKow as the primary descriptor, percentage biodegradability of test chemical 4 -nitrobenzene-1,3 -diamine (CAS No. 5131 -58 -8) was estimated.Test substance undergoes 0.85% degradation by BOD in 28 days. Thus, based on percentage degradation, the test chemical 4-nitrobenzene-1,3-diamine was estimated to be not readily biodegradable in water.

 

In another prediction using the Estimation Programs Interface Suite (EPI suite, 2017), the biodegradation potential of the test compound 4 -nitrobenzene-1,3 -diamine (CAS No. 5131 -58 -8) 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 4-nitrobenzene-1,3 -diamine is expected to be not readily biodegradable.

 

In a supporting weight of evidence study from authoritative database (J-CHECK, 2017), biodegradation screening test was conducted for 14 days (2 weeks) for evaluating the percentage biodegradability of the read across substance 4-nitroaniline (CAS no. 100 -01 -6). Concentration of inoculum i.e, 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 0% by BOD and 2.9% by TOC removal parameter in 14 days. Thus, based on percentage degradation, substance 4-nitroaniline is considered to be not readily biodegradable in nature.

 

For the same read across chemical 4-nitroaniline (CAS no. 100 -01 -6), biodegradation test was conducted for 20 days for evaluating the percentage biodegradability of the read across substance 4-nitroaniline (P. PITTER, 1976). Activated sludge was used as a test inoculum. Activated sludge taken from a sewage plant is cultivated in a 1000ml volumetric cylinder. The mixture is aerated with pressure air. Every day 200 ml of the mixture is driven off so that the sludge age is 5 days. After driving off the 200ml of the mixture aeration is interrupted, and after sedimentation ca. 600mlof the liquid phase is driven off. The residue (200 ml of the thickened activated sludge) is diluted with tap water to the volume ofca.800 ml and 600 mg/l of starch or glucose, 600 mg/l of peptone, 25 ml of a phosphate buffer pH 7.2, and the solution of the tested compound are added. Then the mixture in the cylinder is made up to 1000ml with tap water and aerated for 23 h (the recirculation ratio is 0-25). After this period the procedure is repeated. The tested substance is dissolved in a beaker in a biological medium in a concentration corresponding to 200mg 1 -I COD. To the biological medium such amount of thickened adapted activated sludge is added to make dry matter of the inoculum 100mgl . The beaker is placed in a dark room with a roughly 3 constant temperature of 20 ± 3 °C on an electromagnetic stirrer. The initial value of COD or organic carbon of the liquid phase are determined. Samples filtered or centrifuged before analysis, are taken at suitable intervals. The decrease of the tested substance in the liquid phase is evaluated by determining COD or organic carbon. With the degree of degradation also the average specific rate of degradation is determined, expressed in terms of mg COD (or organic carbon) removed by a gramme of dry matter of the activated sludge per hour. The experiment is carried out till there is no decrease of COD. After that time the total percentage of COD removed and the rate of degradation are evaluated. Conc of test substance used for the study was 200mg/l, respectively. The percentage degradation of read across substance was determined to be 0% by COD parameter in 20 days. Thus, based on percentage degradation, substance 4-nitroaniline is considered to be not readily biodegradable in nature.

 

Another weight of evidence study of biodegradation from authoritative database (J-CHECK, 2017) of the read across substance 2,4-dinitroaniline (CAS no. 97 -02 -9) was conducted for 28 days. Concentration of inoculum i.e, 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 4 and 3% degradation by BOD and HPLC parameter in 28 days. Thus, based on percentage degradation, substance 2,4-dinitroaniline is considered to be not readily biodegradable in nature.

 

On the basis of above results for target chemical 4 -nitrobenzene-1,3 -diamine (from OECD QSAR toolbox version 3.4 and EPI Suite, 2017) and for its read across substance (from authoritative database J-CHECK, 2017 and peer reviewed journal), it can be concluded that the test substance 4 -nitrobenzene-1,3 -diamine can 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

4 -nitrobenzene-1,3 -diamine (CAS No. 5131 -58 -8). If released in to the environment, 21.1% of the chemical will partition into water according to the Mackay fugacity model level III and the half-life period of 4-nitrobenzene-1,3-diamine in water is estimated to be 37.5 days (900 hrs). The half-life (37.5 days estimated by EPI suite) indicates that the chemical is not persistent in water and the exposure risk to aquatic animals is moderate to low whereas the half-life period of 4 -nitrobenzene-1,3 -diamine in sediment is estimated to be 337.5 days (8100 hrs). However, as the percentage release of test chemical 4 -nitrobenzene-1,3 -diamine into the sediment is less than 1% (i.e, reported as 0.0941%), indicates that 4-nitrobenzene-1,3-diamine is not persistent in sediment.

Biodegradation in soil

The half-life period of 4-nitrobenzene-1,3-diamine (CAS No. 5131 -58 -8) 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, 78.8% of the chemical will partition into soil according to the Mackay fugacity model level III. The half-life period of 4-nitrobenzene-1,3-diamine in soil is estimated to be 75 days (1800 hrs). Based on this half-life value of 4 -nitrobenzene-1,3 -diamine, 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 4 -nitrobenzene-1,3 -diamine can be considered to be not readily biodegradable in nature.

 

Bioaccumulation: aquatic / sediment

Four studies including experimental data from authorative database and predicted data from validated models for bioaccumulation (BCF) endpoint of target chemical 4-nitrobenzene-1,3-diamine (Cas no. 5131-58-8) were summarized as follows: 

 

First study for target chemical (Cas no. 5131-58 -8) which suggest an estimated BCF value of 3 was calculated in fish for 4-nitro-1,3-benzenediamine ,using an estimated log Kow of 0.55 and a regression-derived equation. This BCF value suggests that the potential for bioconcentration in aquatic organisms (fish) is low. (HSDB database by US EPA; 2017)

 

Above result is supported by prediction using BCFBAF (v3.00) model and PBT profiler which indicate the estimated bio concentration factor (BCF) for 4-nitro-1,3-benzenediamine is 3.2 L/kg wet-wt which does not exceed the bioconcentration threshold of 2000. Thus it is concluded that 4-nitro-1,3-benzenediamine is not expected to bio accumulate in the aquatic environment.

 

Above prediction is further assisted by Scifinder database which suggest the Bioconcentration factor (BCF) for target chemical 4-nitrobenzene-1,3-diamine was estimated to be 1.0 at pH 1, 1.68 at pH 2, 1.85-1.88 at pH range 3-10 at temperature 25 deg.C.Based on the BCF concentration at all range of pH it is concluded that the test chemical 4-nitrobenzene-1,3-diamine is non bioaccumulative in nature as it does not exceed the BCF criteria of 2000.

Chemspider - ACD/PhysChem Suite prediction model indicate the Bioconcentration factor (BCF) for target chemical 4-nitrobenzene-1,3-diamine was estimated to be 5.10 at pH 5.5 and 7.4 at temperature 25 deg.C. Based on the BCF concentration at two different pH concluded that the test chemical 4-nitrobenzene-1,3-diamine is non bioaccumulative in nature as it does not exceed the BCF criteria of 2000.

Thus based on all available studies for bioaccumulation endpoint concluded that the test substance 4-nitrobenzene-1,3-diamine (Cas no. 5131-58-8) is expected to be non Bioaccumulative in aquatic environment.

Adsorption / desorption

Four studies including experimental studies and predicted data from validated models for adsorption (KOC) endpoint of target chemical 4-nitrobenzene-1,3-diamine (Cas no. 5131-58-8) were summarized as follows:

 

First study from authorative database (HSDB by US EPA; 2017) indicate the Koc of 4-nitrobenzene-1,3-diamine is estimated as 85, using a structure estimation method based on molecular connectivity indices. This estimated Koc value suggests that 4-nitro-1,3-benzenediamine is expected to have high mobility in soil.

Above results was supported by prediction by KOCWIN model (v2.00) of EPI suite which indicate the adsorption value of 4-nitrobenzene-1,3-diamine was estimated as 53.61 L/kg(log Koc=1.72) by means of MCI method at 25 deg.C. This Koc value indicates that the substance 4-nitrobenzene-1,3-diamine has a Low sorption to soil and sediment and therefore have rapid migration potential to groundwater.

 

Scifinder database suggest the soil adsorption coefficient i.e Koc value of test substance 4-nitrobenzene-1,3-diamine was estimated to be 25.0 (Log koc-1.39) at pH 1, 48.8 (Log koc-1.68) at pH 2,54.0 (Log koc-1.73) at pH 3 and 54.6 (Log koc-1.73) at pH range 4-10 at temperature 25 deg.C. This Koc value at all range of pH condition indicates that the substance 4-nitrobenzene-1,3-diamine has negligible sorption to soil and sediment and therefore have rapid migration potential to groundwater.

Further, Chemspider - ACD/PhysChem Suite indicate the soil adsorption coefficient i.e Koc value of test substance 4-nitrobenzene-1,3-diamine was estimated to be 111.74 (log koc: 2.04) at pH 5.5 and pH 7.4 and temp.25 deg.C this Koc value at different pH indicates that the substance 4-nitrobenzene-1,3-diamine has negligible to low sorption to soil and sediment and therefore have rapid to moderate migration potential to groundwater.

 

Thus all available studies for adsorption endpoint concluded that the test substance 4-nitrobenzene-1,3-diamine (Cas no. 5131-58-8) is expected to have high mobility in soil and sediment compartment.