Registration Dossier

Environmental fate & pathways

Biodegradation in water: screening tests

Currently viewing:

Administrative data

Link to relevant study record(s)

Reference
Endpoint:
biodegradation in water: ready biodegradability
Type of information:
calculation (if not (Q)SAR)
Adequacy of study:
weight of evidence
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
accepted calculation method
Justification for type of information:
Data is from computational model developed by USEPA
Qualifier:
according to
Guideline:
other: Modeling database
Principles of method if other than guideline:
The Biodegradation Probability Program (BIOWIN) estimates the probability for the rapid aerobic biodegradation of an organic chemical in the presence of mixed populations of environmental microorganisms .The model is part of the EpiSuite program of the US-EPA. Estimations are made with BIOWIN version 4.10. Estimates are based upon fragment constants that were developed using multiple linear and non-linear regression analyses. Experimental biodegradation data for the multiple linear and non-linear regressions were obtained from Syracuse Research Corporation's (SRC) data base of evaluated biodegradation data (Howard et. al., 1987). This version (v4.10) designates the models as follows (see also Boethling et al. 2003):Biowin1 = linear probability modelBiowin2 = nonlinear probability modelBiowin3 = expert survey ultimate biodegradation modelBiowin4 = expert survey primary biodegradation modelBiowin5 = MITI linear modelBiowin6 = MITI nonlinear modelBiowin7 = anaerobic biodegradation model
GLP compliance:
not specified
Specific details on test material used for the study:
- Name of the test material (IUPAC name): Reaction mass of Methylium, tris[4-​(diethylamino)​phenyl]​-​ & acetate- Molecular weight: 515.7375 g/mol- Molecular formula: C33H45N3O2- Smiles: CCN(CC)C1=CC=C(C=C1)C(=C2C=CC(=[N+](CC)CC)C=C2)C3=CC=C(C=C3)N(CC)CC.CC(=O)[O-]- Inchl: 1S/C31H42N3.C2H4O2/c1-7-32(8-2)28-19-13-25(14-20-28)31(26-15-21-29(22-16-26)33(9-3)10-4)27-17-23-30(24-18-27)34(11-5)12-6;1-2(3)4/h13-24H,7-12H2,1-6H3;1H3,(H,3,4)/q+1;/p-1- Substance type: Organic- Physical state: Solid & liquid
Oxygen conditions:
other: aerobic (Biowin 1-6) and anaerobic (Biowin 7)
Inoculum or test system:
other: mixed populations of environmental microorganisms
Details on study design:
Using the computer tool BIOWIN v4.10 by US-EPA (EPIWIN) the aerobic as well as the anaerobic biodegradability of the test material can be estimated. The follwoing seven different models are used by the tool: Linear Model, Non-Linear Model, Ultimate Biodegradation Timeframe, Primary Biodegradation Timeframe, MITI LInear Model, MITI Non-Linear Model and Anaerobic Model (calles Biowin 1-7, respectively). Due to this results the overall prediction of readily biodegradability is done for the desired chemical.Biowin 1 and 2, are intended to convey a general indication of biodegradability under aerobic conditions, and not for any particular medium. Biowin 1 (Linear model)The fast biodegradation probability for any compound is calculated by summing, for all the fragments present in that compound, the fragment coefficient multiplied by the number of instances of the fragment in the compound (for MW, the value of that parameter is multiplied by its coefficient), and then adding this summation to the equation constant which is 0.7475. The summed values for each fragment coefficient multiplied by the number of instances appear in the "VALUE" column of the linear results screen. Biowin 2 (Non-linear model)Calculation of the fast biodegradation probability for any compound begins by summing, for all the fragments present in that compound, the fragment coefficient multiplied by the number of instances of the fragment in the compound (for MW, the value of that parameter is multiplied by its coefficient), then adding this summation to the equation constant which is 3.0087. The summed values for each fragment coefficient multiplied by the number of instances appear in the "VALUE" column of the non-linear results screen. The non-linear fast biodegradation probability is then calculated from the logistic equation as follows, where total = 3.0087 + the summation as described above:Biowin 3 and 4 yield estimates for the time required to achieve complete ultimate and primary biodegradation in a typical or "evaluative" aquatic environment.Biowin 5 and 6 are predictive models for assessing a compound’s biodegradability in the Japanese MITI (Ministry of International Trade and Industry) ready biodegradation test; i.e. OECD 301C. These models use an approach similar to that used to develop Biowin1 and 2. This protocol for determining ready biodegradability is among six officially approved as ready biodegradability test guidelines of the OECD (Organization for Economic Cooperation and Development). A total dataset of 884 chemicals was compiled to derive the fragment probability values that are applied in this MITI Biodegradability method. The dataset consists of 385 chemical that were critically evaluated as "readily degradable" and 499 chemicals that were critically evaluated as "not readily biodegradable". Biowin 7, the anaerobic biodegradation model, is the most recent. As for the other Biowin models, multiple (linear) regression against molecular fragments was used to develop the model, which predicts probability of rapid degradation in the "serum bottle" anaerobic biodegradation screening test. This endpoint is assumed to be predictive of degradation in a typical anaerobic digester. Biowin7 estimates the probability of fast biodegradation under methanogenic anaerobic conditions; specifically, under the conditions of the "serum bottle" anaerobic biodegradation screening test (Meylan et al. 2007). A total of 169 compounds with serum bottle test data were identified for use in model development. Out of seven different Biowin models, Biowin model 3 and 4 will help in estimating biodgeradability of the test chemical which was described as below-Ultimate Biodegradation Timeframe and Primary Biodegradation Timeframe (Biowin 3 and 4)These two models estimate the time required for "complete" ultimate and primary biodegradation.  Primary biodegradation is the transformation of a parent compound to an initial metabolite.  Ultimate biodegradation is the transformation of a parent compound to carbon dioxide and water, mineral oxides of any other elements present in the test compound, and new cell material. Then the rating was given to each model, which indicates the time required to achieve ultimate and primary biodegradation in a typical or "evaluative" aquatic environment. The ratings for each compound were averaged to obtain a single value for modeling.  The ultimate or primary rating of a compound is calculated by summing, for all the fragments present in that compound.
Key result
Remarks on result:
other: not readily biodegradable as estimated by BIOWIN model
Validity criteria fulfilled:
not specified
Interpretation of results:
not readily biodegradable
Conclusions:
The biodegradability of the substance was calculated using seven different Biowin 1-7 models of the BIOWIN v4.10 software. The results indicate that the test chemical Reaction mass of Methylium, tris[4-​(diethylamino)​phenyl]​-​ & acetate is expected to be not readily biodegradable.
Executive summary:

Estimation Programs Interface Suite was run to predict the biodegradation potential of the test compound  Reaction mass of Methylium, tris[4-​(diethylamino)​phenyl]​-​ & acetate 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 Reaction mass of Methylium, tris[4-​(diethylamino)​phenyl]​-​ & acetate is expected to be not readily biodegradable.

Description of key information

Estimation Programs Interface Suite was run to predict the biodegradation potential of the test compound  Reaction mass of Methylium, tris[4-​(diethylamino)​phenyl]​-​ & acetate 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 Reaction mass of Methylium, tris[4-​(diethylamino)​phenyl]​-​ & acetate is expected to be not readily biodegradable.

Key value for chemical safety assessment

Biodegradation in water:
under test conditions no biodegradation observed

Additional information

Predicted data for the target compound Reaction mass of Methylium, tris[4-​(diethylamino)​phenyl]​-​ & acetate 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 done using the Estimation Programs Interface Suite was run to predict the biodegradation potential of the test compound Reaction mass of Methylium, tris[4-​(diethylamino)​phenyl]​-​ & acetate 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 Reaction mass of Methylium, tris[4-​(diethylamino)​phenyl]​-​ & acetate is expected to be not readily biodegradable.

 

In a supporting weight of evidence study from study report (2018),28-days Closed Bottle test following the OECD guideline 301 D to determine the ready biodegradability of the test item. The study was performed at a temperature of 20°C. The test system included control, test item and reference item. Polyseed were used for this study. 1 polyseed capsule were added in 500 ml D.I water and then stirred for 1 hour for proper mixing and functioning of inoculum. This gave the bacterial count as 107 to 108 CFU/ml. At the regular interval microbial plating was also performed on agar to confirm the vitality and CFU count of microorganism. 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. OECD mineral medium was used for the study. ThOD (Theoretical oxygen demand) of test and reference item was determined by calculation. % degradation was calculated using the values of BOD and ThOD for test item and reference item. The % degradation of procedure control (reference item) was also calculated using BOD & ThOD and was determined to be 73.49%. Degradation of Sodium Benzoate exceeds 31.32% on 7 days & 49.39% on 14th day. The activity of the inoculum is thus verified and the test can be considered as valid. The BOD35 value of test chemical was observed to be 0.52 mgO2/mg. ThOD was calculated as 2.31 mgO2/mg. Accordingly, the % degradation of the test item after 28 days of incubation at 20 ± 1°C according to Closed Bottle test was determined to be 22.51%. Based on the results, the test item, under the test conditions, was not readily biodegradable in nature.

 

For the test chemical,Biodegradation study was conducted for evaluating the percentage biodegradability of test substance(Toshihide Saito et. al., 1984). Activated sludge was used as a test inoculum obtained from municipal sewage. Test substance of conc. 500 mg/l was prepared and diluted as needed. The COD measurement was performed by the potassium dichromate reflux method based on Japanese Industrial Standards. In the BOD measurement, a sample solution was taken into a container. Then JIS-BOD testing solutions, i.e. 3 ml of A solution and 1 ml of B, C, D solutions were added to the sample solution, respectively. Then 5 ml of the supernatant of the municipal sewage activated sludge was added to the sample solution and diluted to 300 ml with water. Immediately, the BOD-time curve was recorded at 20~ using an Ohkura OM-200I type coulometer. The TOC measurement was carried out by a Yanagimoto TOC-ILW.BOD5, COD, ThOD and TOC value of the test chemical was determined to be 0.038, 1.73, 2.88 and 0.50 g/g, respectively. The BOD5/TOC ratio of test chemical was determined to be 0.08 (i.e. ranges in between 0.08-0.89), indicating that the test chemical is highly resistant to aerobic biodegradation. Thus, based on this value BOD5/TOC value, it can be concluded that test chemical is not readily biodegradable in nature.

 

In a supporting weight of evidence study from peer reviewed journal (H. Heukelekian et. al., 1955),Biodegradation experiment was conducted for 5 days for evaluating the percentage biodegradability of test substance using standard dilution method under aerobic conditions at a temperature of 20°C. Sewage was used as a test inoculum. The 5 day BOD value of test chemical was determined to be 0 g/g. Thus, based on this value, test chemical is considered to be not readily biodegradable in nature.

 

On the basis of above results for target chemical Reaction mass of Methylium, tris[4-​(diethylamino)​phenyl]​-​ & acetate (from modelling database, 2018), it can be concluded that the test substance Reaction mass of Methylium, tris[4-​(diethylamino)​phenyl]​-​ & acetate can be expected to be not readily biodegradable in nature.