3,3'-[[4-[(2-chloro-4-nitrophenyl)azo]phenyl]imino]bis[propiononitrile]

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

biodegradation in water: screening test, other

Remarks:

BOD5/COD

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

August 23, 1993

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Qualifier:

according to guideline

Guideline:

other: DEV DIN 38'409-41-1 (1980)

Deviations:

yes

Remarks:

mean of 2 determinations instead of 3

Qualifier:

according to guideline

Guideline:

ISO 5815 (Water quality - Determination of Biochemical Oxygen Demand after 5 Days (BOD5) - Dilution and Seeding Method)

Deviations:

yes

Remarks:

aerate over night after addition of the inoculum

Principles of method if other than guideline:

SAV: 02 000 02 for determinatiion of COD
SAV: 01 000 01 for determination of BOD5

GLP compliance:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

other: seeding water of an urban waste water

Duration of test (contact time):

ca. 5 d

Initial conc.:

ca. 398.9 mg/L

Based on:

test mat.

Remarks:

for the calculation of BOD5

Initial conc.:

ca. 199.5 mg/L

Based on:

test mat.

Remarks:

for the calculation of BOD5

Initial conc.:

ca. 99.7 mg/L

Based on:

test mat.

Remarks:

for the calculation of BOD5

Initial conc.:

ca. 49.9 mg/L

Based on:

test mat.

Remarks:

for the calculation of BOD5

Initial conc.:

ca. 24.9 mg/L

Based on:

test mat.

Remarks:

for the calculation of BOD5

Initial conc.:

ca. 12.5 mg/L

Based on:

test mat.

Remarks:

for the calculation of BOD5

Initial conc.:

ca. 6.2 mg/L

Based on:

test mat.

Remarks:

for the calculation of BOD5

Initial conc.:

ca. 8.25 other: mg

Based on:

test mat.

Remarks:

for the calculation of COD

Initial conc.:

ca. 8.16 other: mg

Based on:

test mat.

Remarks:

for the calculation of COD

Parameter followed for biodegradation estimation:

other: BOD5/COD

Reference substance:

other: D(+) - Glucose / L-Glutamic acid (BOD5)

Reference substance:

other: Potassium Hydrogen Phtalate Solution (COD)

Parameter:

BOD5

Value:

ca. 0 mg O2/g test mat.

Parameter:

COD

Value:

ca. 618 mg O2/g test mat.

Results with reference substance:

The BOD5 of glucose/glutamic acid solution is: 200 mg O2/I The COD of Potassium hydrogen phthalate is (Criteria: 200 ± 8 mg O2/I): 198 mg O2/I

Validity criteria fulfilled:

not specified

Interpretation of results:

not readily biodegradable

Conclusions:

BOD5 = 0 mg O2/g
COD = 618 mg O2/g
BOD5/COD = 0

Executive summary:

Method

The Biological Oxygen Demand of test substance was determined according to the ISO 5815 (Water quality - Determination of Biochemical Oxygen Demand after 5 Days (BOD5) - Dilution and Seeding Method), while the Chemical Oxygen Demand was determined according to the DEV DIN 38*409 - H 41-1 (1980).

 

Result

BOD5 = 0 mg O₂/g

COD = 618 mg O₂/g

BOD5/COD = 0

Reference 2

Endpoint:

biodegradation in water: ready biodegradability

Remarks:

prediction

Type of information:

(Q)SAR

Adequacy of study:

supporting study

Study period:

2020

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: accepted calculation method

Justification for type of information:

QSAR estimation

Qualifier:

no guideline required

Principles of method if other than guideline:

QSAR dyes R&C report produced by version QSAR dyes RC 2.0 Developed by Milano Chemometrics and QSAR research group Dept. Earth and Environmental Science, University Milano
Bicocca, Italy.

Parameter:

probability of ready biodegradability (QSAR/QSPR)

Remarks on result:

not readily biodegradable based on QSAR/QSPR prediction

Validity criteria fulfilled:

not applicable

Remarks:

estimation by prediction tool

Interpretation of results:

not readily biodegradable

Conclusions:

Based on prediction carried out with the prediction tool, the substance resulted as non ready biodegradable.

Executive summary:

Results:

The substance was predicted not to be ready biodegradable.

Reference 3

Endpoint:

biodegradation in water: inherent biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From Septemper 16, 1993 to September 30, 1993

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 C (Ready Biodegradability: Modified MITI Test (I))

Deviations:

yes

Remarks:

Guideline - Temperature : 20 ± 2°C - Test medium : solution A - Study Plan Duration : 14 days Instead of 28 days - The test has been finished after 14 days since no degradation activity could be observed.

GLP compliance:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

sewage, domestic (adaptation not specified)

Details on inoculum:

- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): mixture of polyvalent bacteria collected 14 September 1993 in the aeration tank of a domestic sewage treatment plant, ARA Basel Communal.
- Concentration of sludge: 30 mg TS/I.

Duration of test (contact time):

ca. 14 d

Initial conc.:

ca. 100 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

TEST CONDITIONS
- Test temperature: 20 ± 2°C
- Continuous darkness: yes

Reference substance:

other: Natriumbenzoat

Parameter:

other: BOD versus ThOD

Value:

ca. 0

Sampling time:

14 d

Results with reference substance:

The % of BOD versus ThOD is: 86% (14 days)

Validity criteria fulfilled:

yes

Interpretation of results:

under test conditions no biodegradation observed

Conclusions:

% of BOD versus ThOD = 0% (14 days)

Executive summary:

Method:

The inherent biodegradability of test substance was determined in a 14 days modified MITI-test according to the OECD Guideline for Testing of Chemicals, No. 301C, 1981.

 

Result:

The biodegradation of the test substance (corrected by the Incoculum control) expressed as the % of BOD versus ThOD is : 0% (14 days).

Reference 4

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

other: expert judgement based on available data

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

accepted calculation method

Justification for type of information:

1. SOFTWARE: EPI Suite

2. MODEL: v4.11

3. BIODEGRADATION MODELS
Linear model (Biowin1)
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.  

Non-linear model (Biowin2)
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 non-linear fast biodegradation probability is then calculated from the logistic equation, where total = 3.0087 + the summation as described above:
non-linear probability  =  exp(total) / (1 + exp(total) )

Ultimate and primary survey model (Biowin3 and Biowin4)
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.  The models are based upon a survey of 17 biodegradation experts conducted by EPA, in which the experts were asked to evaluate 200 compounds in terms of the time required to achieve ultimate and primary biodegradation in a typical or "evaluative" aquatic environment (Boethling et al. 1994).  Each expert rated the ultimate and primary biodegradation of each compound on a scale of 1 to 5. The ratings correspond to the following time units:   5 - hours;  4 - days;  3 - weeks;  2 - months;  1 - longer.   It should be noted that the ratings are only semi-quantitative and are not half-lives.  
The ultimate or primary rating of a 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 3.1992 for Biowin3 and 3.8477 for Biowin4. 

Calculated rating                         Words assigned, representing expected total
(numerical value from model)       degradation time
>4.75 - 5                                 hours
>4.25 - 4.75                                 hours to days
>3.75 - 4.25                                 days
>3.25 - 3.75                                 days to weeks
>2.75 - 3.25                                weeks
>2.25 - 2.75                               weeks to months        
>1.75 - 2.25                                 months
<1.75                                         recalcitrant


Linear and Non-Linear MITI Biodegradation Model (Biowin 5 and Biowin 6)
Under its Chemical Substances Control Law (CSCL), the Japanese have tested approximately 900 discrete substances in the Ministry of International Trade and Industry (MITI)-1 test.  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".
The 884 compound dataset was divided into a training dataset (589 compounds) and a validation dataset (295 compounds).  The critical biodegradation evaluations (results of the MITI tests) were either "readily degradable" or "not readily degradable"; "readily degradable" was assigned a numeric value of 1 and "not readily degradable" was assigned a numeric value of 0 (0 to 1 is the full probability range). The basic approach for deriving the fragment values is very similar to the approach used for the original linear/non-linear model described above.
Although the majority of fragments in the new MITI models are identical to fragments in the models described above, the new MITI models incorporate various changes.  For example, to provide fuller characterization of alkyl chain length and branching, the original C4 terminal alkyl group fragment was replaced with a fragment set consisting of -CH3, -CH2 (both linear and ring types), -CH (both linear and ring types), and -C=CH (alkenyl hydrogen). The final MITI models contain 42 fragments and molecular weight as independent variables.

Anaerobic Biodegradation Model (Biowin 7)
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.  This data set was not separated into separate training and validation sets: all available compounds were used for the regression. Each compound was scored "pass" or "fail" using 60% of theoretical gas production in 56 days (i.e. normal test duration) as the pass criterion; for model regression, Pass=1 and Fail=0.A set of 37 fragments was developed using existing fragments from the other BIOWIN models. Molecular weight is not used as a predictive variable. The probability of fast biodegradation 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, and then adding this summation to the equation constant which is 0.8361.  

Guideline:

other: REACH Guidance on QSARs R.6

Inoculum or test system:

other: expert judgement

Parameter:

probability of ready biodegradability (QSAR/QSPR)

Remarks on result:

not readily biodegradable based on QSAR/QSPR prediction

Details on results:

Probability of Rapid Biodegradation (BIOWIN v4.10)
Biowin1 (Linear Model): 0.2950
Biowin2 (Non-Linear Model): 0.0013

Expert Survey Biodegradation Results:
Biowin3 (Ultimate Survey Model): 1.6894 (recalcitrant)
Biowin4 (Primary Survey Model): 3.0121 (weeks)

MITI Biodegradation Probability:
Biowin5 (MITI Linear Model): -0.0616
Biowin6 (MITI Non-Linear Model): 0.0000

Anaerobic Biodegradation Probability:
Biowin7 (Anaerobic Linear Model): -1.0200

Ready Biodegradability Prediction: NO

Ready Biodegradability Prediction: YES or NO

 

The criteria for the YES or NO prediction are as follows:  if the Biowin3 (ultimate survey model) result is "weeks" or faster (i.e. days, days to weeks, or weeks) AND the Biowin5 (MITI linear model) probability is >= 0.5, then the prediction is YES (readily biodegradable).  If this condition is not satisfied, the prediction is NO (not readily biodegradable).

 

This method is based on the application of Bayesian analysis to ready biodegradation data for US Pre-manufacture Notification (PMN) chemicals, derived collectively from all six OECD301 test methods plus OECD310.  The approach is fully described in Boethling et al. (2004).

 

The linear and non-linear MITI models (Biowin5 and 6) also predict ready biodegradability, but for degradation in the OECD301C test only, and based exclusively on data from the Chemicals Evaluation and Research Institute Japan (CERIJ) database (http://www.cerij.or.jp/ceri_en/otoiawase/otoiawase_menu.html).

Validity criteria fulfilled:

not applicable

Remarks:

estimation by EPI Suite and QSAR dyes

Interpretation of results:

not readily biodegradable

Conclusions:

Based on prediction carried out with EPI Suite and QSAR dyes, the substance resulted as non ready biodegradable.

Executive summary:

Method:

Estimate of probability of rapid biodegradation relying on BIOWIN v4.10 in EPI Suite prediction tool and QSAR dyes. The overall assessment is based on the responses given by different predictive models for biodegradability under various conditions: linear and non-linear models, ultimate and primary survey models, MITI linear and non-linear models, anaerobic linear model.

 

Results:

The substance was predicted to be not ready biodegradable.

Description of key information

Not readily biodegradable

Key value for chemical safety assessment

Biodegradation in water:

not biodegradable

Type of water:

freshwater

Additional information

Different available tests may be valuable that give information on biodegradability.

Missing the Ready biodegradability test.

 

Inherent biodegradability:

The inherent biodegradability was determined in a 14 days modified MITI-test according to the OECD Guideline for Testing of Chemicals, No. 301C, 1981. The test has been performed in compliance with the Procedures and Principles of Good Laboratory Practice, regulation of Switzerland. The test substance was tested in concentrations of 100 mg/L.

The biodegradation of the test substance (corrected by the Incoculum control) expressed as the % of BOD versus ThOD is 0%.

The % of BOD versus ThOD calculated for the reference substance (natriumbenzoat) is 86% (14 days).

 

BOD5/COD ratio:

Biological Oxygen Demand (BOD5) and Chemical Oxygen Demand (COD) are the most commonly used parameters for the characterization of the biodegradability capacity.

COD results are typically higher than BOD5 values, and the ratio between vary depending on the characteristics of the substrate. This ratio has been commonly used as an indicator for biodegradation capacity, the "Biodegradability index" (B.I.).

As indicated in ECHA Guidance requirement R.7B, the BOD₅ test is a traditional biodegradation test that is now replaced by the ready biodegradability tests. Therefore, this test should not be performed today for assessment of the ready biodegradability of substances.

Older test data may, however, be used when no other degradability data are available.

Studies on BOD₅ and COD are available for this substance, therefore they have been used together with the inherent biodegradability OECD 301C.

COD was measured according to the DEV DIN 38*409 - H 41-1 (1980). The COD measured was 618 mg/g O₂.

BOD₅ was measured according to the ISO 5815 (Water quality - Determination of Biochemical Oxygen Demand after 5 Days (BOD₅) - Dilution and Seeding Method). The BOD₅ measured was 0 mg/g O₂.

The ratio BOD₅/COD is 0.

This result is in line with the BOD₅/COD value calculated in other tests reported in the file attached below.