4-(phenylazo)benzene-1,3-diamine acetate

Endpoint summary

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 4-(phenylazo)benzene-1,3-diamine acetate(CAS no. 79234 -33 -6) 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 4-(phenylazo)benzene-1,3-diamine acetate is expected to be not readily biodegradable.

Additional information

Biodegradation in water:

Predicted data study for target chemical 4-(phenylazo)benzene-1,3-diamine acetate (CAS No. 79234 -33 -6) and experimental studies for its structurally similar read across chemicals have been reviewed for biodegradation in water endpoint and their results are summarized below

 

First study was predicted data study in this study the Estimation Programs Interface Suite (EPI suite, 2018) was run to predict the biodegradation potential of the test compound 4-(phenylazo)benzene-1,3-diamine acetate(CAS no. 79234 -33 -6) 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 4-(phenylazo)benzene-1,3-diamine acetate is expected to be not readily biodegradable.

 

Further, to support above predicted data experimental study was done from UERL lab in this study the biodegradation experiment was carried out 35-days Closed Bottle test following the OECD guideline 301 D to determine the ready biodegradability of the read across chemical 4-(phenylazo)benzene-1,3-

diamine, CAS No. 495-54-5. The test system included control, test item and reference item. The concentration of test and reference item (Sodium Benzoate) chosen for both the study was 4 mg/L, while that of inoculum was 32 ml/l. ThOD (Theoretical oxygen demand) of read across and reference item was determined by calculation. % degradation was calculated using the values of BOD and ThOD for test item and reference item. The BOD35 value of 4-(phenylazo)benzene-1,3-diamine, CAS No. 495-54-5 was observed to be 0.7 mgO2/mg. ThOD was calculated as 1.80 mgO2/mg. Accordingly, the % degradation of the test item after 35 days of incubation at 20 ± 1°C according to Closed Bottle test was determined to be 38.88%. Based on the results, the read across chemical, under the test conditions, was considered to be not readily biodegradable over a period of 35 days.

 

 Next study was experimental study was reviewed from Water Research Journal in this study the Biodegradation experiment was conducted for 20 days for evaluating the percentage biodegradability of the substance 4-nitroaniline (CAS no. 100 -01 -6). 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. 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 samples were 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 test substance was determined to be 0% by COD parameter in 20 days. Thus, based on percentage degradation, read across substance 4-nitroaniline was considered to be not readily biodegradable in nature.

 

On the basis of predicted data study for target chemical 4-(phenylazo)benzene-1,3-diamine acetate(CAS no. 79234 -33 -6) and experimental studies for its structurally similar read across chemical it can be concluded that test chemical is expected to be not readily biodegradable.