1,5-Pentanediamine, 2-methyl-, reaction products with 2-ethyl-1,4-butanediamine and glycidyl tolyl ether

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

22 March 2018 - 19 April 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test)

Version / remarks:

1992

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.4-D (Determination of the "Ready" Biodegradability - Manometric Respirometry Test)

Version / remarks:

2008

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 835.3110 (Ready Biodegradability)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Oxygen conditions:

aerobic

Inoculum or test system:

sewage, predominantly domestic, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): A mixed population of sewage treatment micro-organisms was obtained on 19 March 2018 from the final effluent stage of the Severn Trent Water Plc sewage treatment plant at Loughborough, Leicestershire, UK, which treats predominantly domestic sewage.
- Preparation of inoculum for exposure: The sample of effluent was filtered through coarse filter paper (first approximate 200 mL discarded) and maintained on aeration in a temperature controlled room at temperatures of between 16 and 21 ºC prior to use.

Duration of test (contact time):

28 d

Initial conc.:

100 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

TEST CONDITIONS
- Composition of medium: mineral medium as recommended in the OECD Guidelines
- Solubilising agent (type and concentration if used): acetone
A nominal amount of test item (1000 mg) was dissolved in 10 mL of acetone to give a 1000 mg/10 mL solvent stock solution. An aliquot (500 µL) of this solvent stock solution was dispensed onto a filter paper and the solvent allowed to evaporate to dryness for approximately 15 minutes. The filter paper was dispersed in approximately 350 mL of mineral medium with the aid of high shear mixing (approximately 7500 rpm, 5 minutes) prior to addition of inoculum. The volume was then adjusted to 500 mL to give a final concentration of 100 mg/L. The volumetric flask containing the solvent stock solution was inverted several times to ensure homogeneity of the solution.
- Test temperature: 20 - 22 ºC
- pH: 7.4 - 7.6 at test start
- pH adjusted: no
- Continuous darkness: diffuse light


TEST SYSTEM
- Culturing apparatus: CES Multi-Channel Aerobic Respirometer
- Number of culture flasks/concentration: 3

SAMPLING
- Sampling frequency: daily

CONTROL AND BLANK SYSTEM
Three replicate bottles containing inoculated mineral medium to act as the inoculum control plus a filter paper.
Two replicate bottles containing inoculated mineral medium plus a filter paper and the reference item, aniline, at a concentration of 100 mg/L.
Two replicate bottles containing the test item on filter paper at a concentration of 100 mg/L in inoculated mineral medium plus the reference item, aniline, at a concentration of 100 mg/L to act as toxicity control vessels.

Reference substance:

aniline

Parameter:

% degradation (O2 consumption)

Value:

0

Sampling time:

28 d

Parameter:

% degradation (O2 consumption)

Remarks:

toxicity control

Value:

31

Sampling time:

14 d

Remarks on result:

other: not toxic to the sewage treatment micro-organisms

Details on results:

The mean BOD of the inoculated mineral medium (control) was 26.45 mg O2/L after 28 days and therefore satisfied the validation criterion given in the OECD Test Guidelines.
The pH of the inoculated test item vessels on Day 28 ranged from 7.7 to 7.8 and hence satisfied the validation criterion given in the OECD Test Guidelines.
The difference between extremes of replicate BOD values at the end of the test was less than 20% and therefore satisfied the validation criterion given in the OECD Test Guidelines.
The test item attained 0% biodegradation after 28 days, calculated from the oxygen consumption values, and therefore cannot be considered to be readily biodegradable under the strict terms and conditions of OECD Guideline No. 301F.
The toxicity control attained 31% biodegradation after 14 days and 34% biodegradation after 28 days thereby confirming that the test item was not toxic to the sewage treatment micro-organisms used in the test.

Results with reference substance:

Aniline (procedure control) attained 67% biodegradation after 14 days and 76% biodegradation after 28 days thereby confirming the suitability of the inoculum and test conditions.

Validity criteria fulfilled:

yes

Interpretation of results:

under test conditions no biodegradation observed

Conclusions:

CGE-PMDA adduct attained 0% biodegradation after 28 days and therefore cannot be considered as readily biodegradable under the strict terms and conditions of OECD Guideline No. 301F.

Executive summary:

The study was performed to assess the ready biodegradability of CGE-PMDA adduct in an aerobic aqueous media. The method followed was designed to be compatible with the OECD Guidelines for Testing of Chemicals (1992) No. 301F, “Ready Biodegradability; Manometric Respirometry Test” referenced as method C.4-D of Commission Regulation (EC) No. 440/2008 and US EPA Fate, Transport, and Transformation Test Guidelines OCSPP 835.3110 (Paragraph (q)).

The test item at a concentration of 100 mg/L was exposed to sewage treatment micro-organisms with mineral medium in sealed culture vessels in diffuse light at temperatures of between 20 and 22 ºC for 28 days. 

Following the recommendations of the International Standards Organisation (ISO 1995), the test item was dissolved in an auxiliary solvent prior to being adsorbed onto a filter paper and subsequent dispersal in test media. Using this method the test item is evenly distributed throughout the test medium and the surface area of test item exposed to the test organisms is increased thereby increasing the potential for biodegradation.

The biodegradation of the test item was assessed by the measurement of daily oxygen consumption values on Days 0 to 28. Control solutions with inoculum and the reference item, aniline, together with a toxicity control were used for validation purposes.

CGE-PMDA adduct attained 0% biodegradation after 28 days and therefore cannot be considered to be readily biodegradable under the strict terms and conditions of OECD Guideline No. 301F.

The toxicity control attained 31% biodegradation after 14 days and 34% biodegradation after 28 days thereby confirming that the test item was not toxic to the sewage treatment micro-organisms used in the test.

Aniline (procedure control) attained 67% biodegradation after 14 days and 76% biodegradation after 28 days thereby confirming the suitability of the inoculum and test conditions.

Reference 2

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

(Q)SAR

Adequacy of study:

key study

Study period:

November 2017

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Justification for type of information:

1. SOFTWARE
Model: BIOWIN v4.10
Submodel: Ready Biodegradation (OECD 301C, MITI): Biowin 5 and Biowin 6

2. SMILES OR OTHER IDENTIFIERS USED AS INPUT FOR THE MODEL
- 1CGE-1MPMD adduct CC(CN)CCCNCC(O)COc1ccccc1C
- 2CGE-1MPDA adduct isomer Cc1ccccc1OCC(O)CNCCCC(C)CNCC(O)COc1ccccc1C
- 3CGE-1MPMD Cc1ccccc1OCC(O)CNCC(C)CCCN(CC(O)COc1ccccc1C)C(O)COc1ccccc1C
- mephenesin Cc1ccccc1OCC(O)CO
- di-CGE Cc1ccccc1OCC(O)COc1ccccc1C
- MPMD CC(CN)CCCN

3. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL
The model estimates the ready biodegradability of an organic compound in the presence of microorganisms in an aqueous medium under aerobic condition. The oxygen uptake of microorganisms is measured for 28 days (biological oxygen demand, BOD). The pass levels for ready biodegradability are 60 % removal of BOD. The compounds were tested following MITI test rules. The 10 days window concept does not apply to the MITI method. The Biowin Biodegradability categorisation scheme is based on the structural fragments used by the MITI Biodegradation Probability Models. Seven biodegradation models are included in Biowin. The dataset for Biowin 5 and 6 consists of 884 organic chemicals of which 385 evaluated as “readily biodegradable” and 499 evaluated as “not readily biodegradable”. Estimations are based on fragment coefficients derived from linear (Biowin 5) or non-linear (Biowin 6) regression analyses depending on the model.

4. APPLICABILITY DOMAIN
Descriptor domain:
- Molecular weight MW: 30.02 ≤ MW ≤ 959.2 [g/mol]
MWs of the components of CGE-PMDA range from 116 to 595 g/mol.

5. ADEQUACY OF THE RESULT
Estimations are based on fragment coefficients derived from linear (Biowin 5) or non-linear (Biowin 6) regression analyses depending on the model. The QSAR models for BIOWIN v4.10 are considered reliable based on the numbers (N) of analogues in the training set, and the accuracy of the prediction for compounds in the training set and validation set.

Qualifier:

according to guideline

Guideline:

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

Principles of method if other than guideline:

Approximately 900 discrete substances were tested in the Ministry of International Trade and Industry (MITI)-I test: Estimation of the aerobic biodegradation of an organic compound in the presence of mixed populations of microorganisms. Biodegradation is expressed as the percentage oxygen uptake. The BIOWIN Biodegradability categorisation scheme is based on the structural fragments used by the MITI Biodegradation Probability Models

GLP compliance:

no

Remarks:

Not applicable for QSAR

Oxygen conditions:

aerobic

Inoculum or test system:

sewage, domestic, non-adapted

Duration of test (contact time):

28 d

Parameter followed for biodegradation estimation:

O2 consumption

Key result

Parameter:

% degradation (O2 consumption)

Value:

< 60

Sampling time:

28 d

Remarks on result:

not readily biodegradable based on QSAR/QSPR prediction

Model	1CGE-1MPMD adduct	2CGE-1MPMD adduct isomer	3CGE-1MPMD	mephenesin	di-CGE	MPMD
Biowin 5 (MITI Linear)	0.57 Readily Degradable	0.56 Readily Degradable	0.43 not Readily Degradable	0.81 Readily Degradable	0.65 Readily Degradable	0.58 Readily Degradable
Biowin 6 (MITI Non-Linear)	0.35 not Readily Degradable	0.18 not Readily Degradable	0.05 not Readily Degradable	0.90 Readily Degradable	0.66 Readily Degradable	0.56 Readily Degradable
VEGA (Ready Biodegradation model, IRFMN)	not Readily Biodegradable	not Readily Biodegradable	not Readily Biodegradable	not Readily Biodegradable	not Readily Biodegradable	Possible Readily Biodegradable

Conclusions:

CGE-PMDA is considered not to be readily biodegradable.

Description of key information

The readily biodegradation potential of CGE-PMDA adduct has been assessed using the QSAR models Biowin 5 and Biowin 6, implemented in BIOWIN v4.10. The QSAR model fulfills the OECD criteria for regulatory acceptance.

The models estimate the ready biodegradability of organic compounds in the presence of microorganisms in aqueous medium under aerobic conditions. The oxygen uptake of microorganisms is measured for 28 days (biological oxygen demand, BOD). The pass levels for ready biodegradability are 60 % removal of BOD. Approximately 900 strict compounds were tested following Japanese Ministry of International Trade and Industry (MITI) test rules. The Biowin Biodegradability categorization scheme is based on the structural fragments used by the MITI Biodegradation Probability Models. The dataset for Biowin 5 and Biowin 6 consists of 884 organic chemicals of which 385 evaluated as “readily biodegradable” and 499 evaluated as “not readily biodegradable”. Estimations are based on fragment coefficients derived from linear (Biowin 5) or non-linear (Biowin 6) regression analyses depending on the model.

CGE-PMDA is a mixture of multi constituents. All constituents are within the descriptor domain (30.02 ≤ MW ≤959.2 [g/mol]).

CGE-PMDA is considered as not readily degradable, although the results of Biowin 5 and Biowin 6 are non-conclusive for the two constituents 1CGE-1MPMD adduct and 2CGE-1MPMD adduct isomer. To validate the result, readily biodegradation was also assessed using the in silico platform VEGA. The results are consistent with Biowin 6 results for 1CGE-1MPMD adduct and 2CGE-1MPDA adduct isomer.

 

CGE-PMDA adduct attained 0% biodegradation after 28 days and therefore cannot be considered as readily biodegradable under the strict terms and conditions of OECD Guideline No. 301F.

The study was performed to assess the ready biodegradability of CGE-PMDA adduct in an aerobic aqueous media. The method followed was designed to be compatible with the OECD Guidelines for Testing of Chemicals (1992) No. 301F, “Ready Biodegradability; Manometric Respirometry Test” referenced as method C.4-D of Commission Regulation (EC) No. 440/2008 and US EPA Fate, Transport, and Transformation Test Guidelines OCSPP 835.3110 (Paragraph (q)).

The test item at a concentration of 100 mg/L was exposed to sewage treatment micro-organisms with mineral medium in sealed culture vessels in diffuse light at temperatures of between 20 and 22 ºC for 28 days. 

Following the recommendations of the International Standards Organisation (ISO 1995), the test item was dissolved in an auxiliary solvent prior to being adsorbed onto a filter paper and subsequent dispersal in test media. Using this method the test item is evenly distributed throughout the test medium and the surface area of test item exposed to the test organisms is increased thereby increasing the potential for biodegradation.

The biodegradation of the test item was assessed by the measurement of daily oxygen consumption values on Days 0 to 28. Control solutions with inoculum and the reference item, aniline, together with a toxicity control were used for validation purposes.

CGE-PMDA adduct attained 0% biodegradation after 28 days and therefore cannot be considered to be readily biodegradable under the strict terms and conditions of OECD Guideline No. 301F.

The toxicity control attained 31% biodegradation after 14 days and 34% biodegradation after 28 days thereby confirming that the test item was not toxic to the sewage treatment micro-organisms used in the test.

Aniline (procedure control) attained 67% biodegradation after 14 days and 76% biodegradation after 28 days thereby confirming the suitability of the inoculum and test conditions.

Key value for chemical safety assessment

Biodegradation in water:

under test conditions no biodegradation observed

Type of water:

freshwater