N-ethyl-N-[2-[1-(2-methylpropoxy)ethoxy]ethyl]-4-(phenylazo)aniline

Mode of degradation in actual use

Administrative data

Endpoint:

mode of degradation in actual use

Type of information:

(Q)SAR

Adequacy of study:

key study

Study period:

Study completed on 21/02/2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

accepted calculation method

Justification for type of information:

As it is concluded that the registered substance is not readily biodegradable, the identification of possible degradation products is a standard information requirement according to column 1, Section 9.2.3. of Annex IX of the REACH Regulation.

Due consideration was given to the approach to fulfil the above requirements. As proposed to ECHA, it was considered that the EAWAG-BBD Pathway Prediction System in conjunction with additional QSAR derivation techniques could be employed for the identification of biodegradation pathways and potential biodegradation products of the target substance. This approach is considered appropriate as an adaption of the standard information requirements of Annex XI to the REACH Regulation. Specifically 1.3. Qualitative or Quantitative structure-activity relationship ((Q)SAR) which states as follows:

Results obtained from valid qualitative or quantitative structure-activity relationship models ((Q)SARs) may indicate the presence or absence of a certain dangerous property. Results of (Q)SARs may be used instead of testing when the following conditions are met:

– results are derived from a (Q)SAR model whose scientific validity has been established: This is fulfilled; recognised QSAR models are utilised.

– the substance falls within the applicability domain of the (Q)SAR model: This is fulfilled; the report attached below details reliability assessments.

– results are adequate for the purpose of classification and labelling and/or risk assessment: This is fulfilled; the identified degradants have been assessed appropriately for PBT and vPvB properties. Potential risk is also mitigated by the use pattern of the substance and negligible exposures.

– adequate and reliable documentation of the applied method is provided. This is fulfilled; suitable QPRF and QMRF documentation is available for inspection upon request by ECHA. Due to the size of the documents they are not included within this summary.

It is considered within the scope of the report attached below, the above criteria are satisfied.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: EAWAG-BBD Pathway Prediction System

Deviations:

not applicable

Principles of method if other than guideline:

The EAWAG-BBD Pathway Prediction System was employed for the identification of biodegradation pathways and potential biodegradation products of the target substance.

The Biodegradation and Bioremediation Database (BBD) of the University of Minnesota, now hosted at EAWAG (Switzerland), contains information on microbial biocatalytic reactions and biodegradation pathways for primarily xenobiotic, chemical compounds. One of the goals of the EAWAG-BBD is to provide information on microbial enzyme-catalyzed reactions that are important for understanding biodegradation of environmental pollutants. Individual reactions and metabolic pathways are presented with information on the starting and intermediate chemical compounds, the organisms that transform the compounds, the enzymes, and the genes. In addition to reactions and pathways, this database also contains a Pathway Prediction System (EAWAG-BBD PPS).
The web-based PPS predicts plausible pathways for microbial degradation of chemical compounds. Predictions use biotransformation rules, based on reactions found in the EAWAG-BBD database or in the scientific literature. A list of all rules is available in the database.

PPS predictions are most accurate for compounds that are:

• similar to compounds whose biodegradation pathways are reported in the scientific literature;
• in environments exposed to air, in moist soil or water, at moderate temperatures and pH, with no competing chemicals or toxins; and
• the sole source of energy, carbon, nitrogen, or other essential element for the microbes in these environments, rather than present in trace amounts.

Biodegradation of some types of compounds, e.g. inorganic chemicals, high MW compounds (polymers and chemicals with MW>1000), chemicals with unknown or variable composition, mixtures and highly fluorinated compounds) should not be predicted with the PPS.

Some known environmental reactions are not predicted, primary because they are not biodegradation reactions. Also, some reactions are too difficult to predict. Examples of reactions not predicted by the PPS are:

• Detoxification reactions (e.g., conjugation with xylose, glucuronate and sulfate).
• Dimerizations (e.g., disulfides formed from sulfide (-SH) groups, or azo compounds formed from primary amide (-NH2) groups).
• Methylation of hydroxyl groups.
• Acetylation of primary amines.
• Formation of intramolecular rings.
• Hydroxylation of aliphatic carbon atoms at positions where pure cultures of organisms that metabolize similar compounds do not hydroxylate, though environmental non-specific monooxygenases may.

The PPS allows to visualize all predicted biotransformations, or only those more likely to occur exposed to air (aerobic likelihood "neutral" or above). Biotransformations are assigned aerobic likelihood by two or more biodegradation experts2. Standard conditions assumed for aerobic biotransformations are: exposed to air, in moist soil or water, at neutral pH, 25°C, with no competing or toxic other compounds.

Likelihood for biotransformation rules is following described.

• Very likely reaction: reactions that will almost certainly occur and occur with the highest priority.
• Likely reaction: i) almost all bacteria can catalyze a given reaction with a functional group present in a molecule; ii) reaction that is significantly likely to occur once a certain intermediate has been generated.
• Possible reaction (neutral): reactions that are common but not certain to occur in every system. These must be looked at individually. Some may be likely, some may be possible and some may be unlikely based on current knowledge.
• Unlikely reaction: reactions that clearly might occur, but are either very rarely catalyzed in bacterial and fungal populations, or that don't seem likely to occur because of the initial used conditions or other chemical/biochemical reason.
• Very unlikely reaction: e.g., reactions that have never been observed under aerobic conditions and the enzymes are oxygen sensitive.

QSAR prediction methodologies and tools
A Quantitative Structure-Activity Relationship (QSAR) is a quantitative (mathematical) relationship between a numerical representation of chemical structure and a biological effect/activity. It often takes the form of regression equation, and can make predictions of effects/activities that are either on a continuous scale or on a categorical scale. The predictions gained by the QSAR models were evaluated in terms of their reliability, as required by OECD principles for the validation, for regulatory purposes, of QSARs. The assessment of the reliability of a QSAR prediction is critical and is therefore a main requirement for the prediction to be accepted by regulatory authorities and initiatives. Therefore, each prediction was provided together with the information on the applicability domain of the model used to derive it. As a general rule, predictions were assigned to four levels of reliability:

i) high reliable: target compound is included in the applicability domain of the model and the prediction is assessed as highly accurate (very limited uncertainty).
ii) moderate reliable: target compound is included in the applicability domain of the model and prediction is assessed as moderately accurate (limited uncertainty).
iii) borderline reliable: target compound is included in the applicability domain of the model, but the level of confidence of the prediction is limited (medium uncertainty).
iv) not reliable: target compound is outside the applicability domain of the model and/or high uncertainty is associated to the prediction.

Several criteria were considered to define the level of reliability, including the applicability domain of the model (e.g. descriptor domain, structural fragment domain) as well as information on training set analogues (e.g., degree of similarity toward the target, consistency of experimental data, prediction accuracy). It is important to highlight that different predictors provide different parameters and information to support the reliability assessment of the generated predictions.

In the present study QSAR predictions were provided for the following toxicological endpoints:
• Reproductive toxicity
• Carcinogenicity

In addition, the registrant conducted assessment of the following endpoints:
• Biodegradation.
• Bioaccumulation.
• Toxicity to aquatic organisms.

Several computational tools are nowadays available for applying in silico approaches. Among them, for QSAR in silico predictions of endpoints of interest the following were selected and used:

• ACD/Percepta (Advanced Chemistry Development, Inc., Pharma Algorithms, Inc.) (rel. 2017)
• ChemTunes Studio (ChemTunes Studio, Toxicity Knowledge Base, v. 1.2, Altamira LLC and Molecular Networks GmbH)
• Leadscope Model Applier (Leadscope, Inc., version 2.2.2, 2017)
• Vega Application (Virtual Models for evaluating the properties of chemicals within a global architecture, version 1.1.4, 2017)
• US EPA BCFBAF v3.01
• US EPA BIOWIN v4.10
• US EPA ECOSAR Version 1.11

These tools were selected according to the OECD Guidance Document on the validation of (Q)SAR models that describes generally accepted guidelines to evaluate if an in silico data is suitable for regulatory use.
In particular, these tools:
1) provide predictions for a defined endpoint;
2) are based on well defined algorithm;
3) assess the prediction in terms of applicability domain;
4) provide models internally and externally validated;
5) provide a mechanistic interpretation of the prediction, when possible.

For each endpoint, the prediction tools were employed and the generated QSAR predictions were assessed for their reliability. The computational assessment documented in the present report is based on the most reliable prediction among the ones provided by different tools. The predictors selected for each endpoint are as described in detail in the attached full report appended below. Criteria from US EPA works are detailed within the attached excel spreadsheet to provide an overall assessment for PBT and vPvB criteria.

GLP compliance:

no

Remarks:

GLP is not applicable to this manner of

Test material

Test material information

Constituent 1

Reference substance name:

N-ethyl-N-[2-[1-(2-methylpropoxy)ethoxy]ethyl]-4-(phenylazo)aniline

EC Number:

252-021-1

EC Name:

N-ethyl-N-[2-[1-(2-methylpropoxy)ethoxy]ethyl]-4-(phenylazo)aniline

Cas Number:

34432-92-3

Molecular formula:

C22H31N3O2

IUPAC Name:

N-ethyl-N-[2-(1-isobutoxyethoxy)ethyl]-4-(phenyldiazenyl)aniline

Test material form:

liquid: viscous

Details on test material:

Name: C.I. Solvent Yellow 124
Batch/Lot Number: S3424 / S3422
Description: Dark Brown Oily Viscous Liquid
Purity: 94.8 % / 94.5%
Expiry Date: 25 April 2018 / 06/04/2018
Storage conditions: Refrigerated
Safety precautions: Routine safety precautions (lab coat, gloves, safety glasses, face mask) for unknown materials were applied to assure personnel health and safety.

Specific details on test material used for the study:

As above.

Results and discussion

Any other information on results incl. tables

For the target substance Solvent Yellow 124, the EAWAG-BBD Pathway Prediction System was employed to identify biodegradation pathways and potential biodegradation products. The SMILES string was used as input file and it was selected to predict only aerobic biotransformations (aerobic likelihood "neutral", “likely” or “very likely” – as explained in Methods section).

 

The predicted pathway is illustrated in Figure 3.1 in the attached report, where the first level of degradation is reported (i.e., every reaction rule implementing a reaction type that is applicable to the target chemical is executed only once; the products found are stored and the reaction generation is stopped). The first level of degradation products includes all compounds with 2 or more Carbon atoms that are generated by “neutral”, “likely” or “very likely” reactions.

 

As it can be observed in Figure 3.1, as a first step (or first “level”), eight possible biodegradation reactions are predicted for the target compound Solvent Yellow 124, leading to 15 biodegradation products. In more detail, the two “likely” biodegradation reactions (green arrows) consist in the oxidative removal of an alkyl group from the tertiary amine, leading to the formation of a secondary amine and an aldehyde (bt0063reaction rule), as illustrated in Figure 3.2 in the attached report.

 

According to the leaving alkyl group, the parent Solvent Yellow 124 could generate the following four biodegradation products:

·    N-{2-[1-(2-methylpropoxy)ethoxy]ethyl}-4-[phenyldiazenyl]aniline (M2) + acetaldehyde (M3)

·    N-ethyl-4-[phenyldiazenyl]aniline (M4) + [1-(2-methylpropoxy)ethoxy]acetaldehyde (M5)

 

It is highlighted that metabolic pathways for acetaldehyde are known and mapped in the KEGG PATHWAY Database6. KEGG PATHWAY is a collection of manually drawn pathway maps representing current knowledge on the molecular interaction, reaction and relation networks.

 

The remaining six reactions, predicted by PPS for the target Solvent Yellow 124 (yellow arrows of Figure 3.1 and detailed in Figure 3.3,), are classified by the system as “neutral”, i.e. possible reactions but not certain to occur in every system.

Four of these reactions are based onbt0023reaction rule (dialiphatic Ether Alcohol + Aldehyde), which generates eight possible products according to the position of the broken ether bond. Breakdown of the diazene (bt0146reaction rule) is also predicted for the target compound generating two aromatic amines, i.e. N1-ethyl-N1-{2-[1-(2-methylpropoxy)ethoxy]ethyl}benzene-1,4-diamine (M14) and aniline (M15) (bt0146reaction rule: Diazene RNH2 + R'NH2). Finally, oxidation of the terminal tertiary aliphatic carbon of the target is predicted by the PPS generating a tertiary alcohol, i.e. 1-{1-[2-(ethyl{4-[phenyldiazenyl]phenyl}amino)ethoxy]ethoxy}-2-methylpropan-2-ol (M16) (bt0241reaction rule: tertiary Aliphatic tertiary Alcohol).

 

For the identification of second level biodegradation products, only compounds generated by likely reactions (i.e., reactions based onbt0063rule) were selected. The EAWAG-BBD Pathway Prediction System was then run to predict aerobic biodegradation pathways for the selected first level products. An overview of the biodegradation diagram is reported in Figure 3.4 in the attached report.As it is illustrated in Figure 3.4, both productsM2andM4undergo to a second oxidation involving the removal of an alkyl group from the secondary amine (bt0063reaction rule) and leading to the formation of the following second level biodegradation products:

 4-[phenyldiazenyl]aniline (M17) + [1-(2-methylpropoxy)ethoxy]acetaldehyde (M5)

 4-[phenyldiazenyl]aniline (M17) + acetaldehyde (M3)

 

For the first level biodegradation productM5, oxidation of the aldehyde is predicted (bt0003reaction rule: Aldehyde Carboxylate), generating the respective second level carboxylic acid, i.e. [1-(2-methylpropoxy)ethoxy]acetic acid (M18). Bothbt0063andbt0003biodegradation reactions are classified as “likely” (green arrows in Figure 3.4).

Aerobic biodegradation rules were finally applied to all second level degradation products and results are following summarised:

 

4-[phenyldiazenyl]aniline (M17) is predicted to undergo to the breakdown of the diazene, generating aniline (M15) and benzene-1,4-diamine (M19) (bt0146reaction rule – “neutral” reaction);

 

[1-(2-methylpropoxy)ethoxy]acetaldehyde (M5) is predicted to undergo oxidation generating the respective carboxylic acid, i.e. [1-(2-methylpropoxy)ethoxy]acetic acid (M18) (bt0003reaction rule – “likely” reaction).

 [1-(2-methylpropoxy)ethoxy]acetic acid (M18) is predicted to undergo to several “neutral” reactions based mainly onbt0023rule (dialiphatic Ether Alcohol + Aldehyde) andbt0241(tertiary Aliphatic tertiary Alcohol), generating degradation products which are rapidly degraded into smaller compounds entering into known metabolic pathways, e.g. acetate7, glycolate8, acetaldehyde, 2-methylpropanoic acid9, 2-propanol10, propane-1,2-diol11 (compounds mapped in the KEGG PATHWAY Database).

 

Concluding, the main identified biodegradation products predicted by PPS are reported in Table 3.1. A list of all of the identified biodegradation products with related chemical information is reported in Appendix A of the attached report.

QSAR predictions for PBT and vPvB profiling

 

Full details of the profiling are included in the report below, and the attached spreadsheet. For clarity, the results of the exercise are as follows:

ID	IUPAC	Carcinogencity
		Prediction	Reliability assessment
2	N-{2-[1-(2-methylpropoxy)ethoxy]ethyl}-4-[phenyldiazenyl]aniline	POSITIVE	Moderate
3	acetaldehyde	POSITIVE - Carc 2	Annex VI
4	N-ethyl-4-[phenyldiazenyl]aniline	POSITIVE	High
5	[1-(2-methylpropoxy)ethoxy]acetaldehyde	NEGATIVE	Borderline
6	1-(2-methylpropoxy)ethan-1-ol	NEGATIVE	Moderate
7	(ethyl{4-[phenyldiazenyl]phenyl}amino)acetaldehyde	POSITIVE	High
8	2-(ethyl{4-[phenyldiazenyl]phenyl}amino)ethan-1-ol	POSITIVE	High
9	2-methylpropyl acetate	NEGATIVE	Moderate
10	2-methylpropan-1-ol	NEGATIVE	REACH dissemination tool
11	2-(ethyl{4-[phenyldiazenyl]phenyl}amino)ethyl acetate	POSITIVE	Moderate
12	1-[2-(ethyl{4-[phenyldiazenyl]phenyl}amino)ethoxy]ethan-1-ol	POSITIVE	Moderate
13	2-methylpropanal	NEGATIVE	REACH dissemination tool
14	N1-ethyl-N1-{2-[1-(2-methylpropoxy)ethoxy]ethyl}benzene-1,4-diamine	POSITIVE	Moderate
15	aniline	POSITIVE - Carc 2	Annex VI
16	1-{1-[2-(ethyl{4-[phenyldiazenyl]phenyl}amino)ethoxy]ethoxy}-2-methylpropan-2-ol	POSITIVE	Moderate
17	4-[phenyldiazenyl]aniline	POSITIVE	High - Study data
18	[1-(2-methylpropoxy)ethoxy]acetic acid	NEGATIVE	Borderline
19	benzene-1,4-diamine	NEGATIVE	REACH dissemination tool

 

ID	IUPAC	Reproductive toxicity
		Prediction	Prediction
2	N-{2-[1-(2-methylpropoxy)ethoxy]ethyl}-4-[phenyldiazenyl]aniline	Out AD	--
3	acetaldehyde	No data	No Data
4	N-ethyl-4-[phenyldiazenyl]aniline	NEGATIVE	Moderate
5	[1-(2-methylpropoxy)ethoxy]acetaldehyde	NEGATIVE	Borderline
6	1-(2-methylpropoxy)ethan-1-ol	--	Not Reliable
7	(ethyl{4-[phenyldiazenyl]phenyl}amino)acetaldehyde	NEGATIVE	Moderate
8	2-(ethyl{4-[phenyldiazenyl]phenyl}amino)ethan-1-ol	NEGATIVE	Moderate
9	2-methylpropyl acetate	POSITIVE	Moderate
10	2-methylpropan-1-ol	NEGATIVE	REACH dissemination tool
11	2-(ethyl{4-[phenyldiazenyl]phenyl}amino)ethyl acetate	POSITIVE	Borderline
12	1-[2-(ethyl{4-[phenyldiazenyl]phenyl}amino)ethoxy]ethan-1-ol	NEGATIVE	Moderate
13	2-methylpropanal	NEGATIVE	REACH dissemination tool
14	N1-ethyl-N1-{2-[1-(2-methylpropoxy)ethoxy]ethyl}benzene-1,4-diamine	--	Not Reliable
15	aniline	NEGATIVE	REACH dissemination tool
16	1-{1-[2-(ethyl{4-[phenyldiazenyl]phenyl}amino)ethoxy]ethoxy}-2-methylpropan-2-ol	NEGATIVE	Borderline
17	4-[phenyldiazenyl]aniline	NEGATIVE	High*
18	[1-(2-methylpropoxy)ethoxy]acetic acid	NEGATIVE	Borderline
19	benzene-1,4-diamine	NEGATIVE	REACH dissemination tool

 

ID	IUPAC	ECOSAR Version 1.11
		Fish 96h LC 50 (mg/l)	Daphnia 48 LC50 (mg/l)	Algae 96 h EC50 (mg/l)
2	N-{2-[1-(2-methylpropoxy)ethoxy]ethyl}-4-[phenyldiazenyl]aniline	0.541	0.406	0.96
3	acetaldehyde	34.28	162.879	152.215
4	N-ethyl-4-[phenyldiazenyl]aniline	1.83	1.277	2.23
5	[1-(2-methylpropoxy)ethoxy]acetaldehyde	48.098	154.137	172.249
6	1-(2-methylpropoxy)ethan-1-ol	2549.715	1251.174	509.785
7	(ethyl{4-[phenyldiazenyl]phenyl}amino)acetaldehyde	1.784	1.185	2.705
8	2-(ethyl{4-[phenyldiazenyl]phenyl}amino)ethan-1-ol	5.283	3.544	5.261
9	2-methylpropyl acetate	21.076	44.89	19.805
10	2-methylpropan-1-ol	778.872	394.678	183.651
11	2-(ethyl{4-[phenyldiazenyl]phenyl}amino)ethyl acetate	0.949	1.461	0.398
12	1-[2-(ethyl{4-[phenyldiazenyl]phenyl}amino)ethoxy]ethan-1-ol	12.621	8.199	10.657
13	2-methylpropanal	18.761	56.668	65.051
14	N1-ethyl-N1-{2-[1-(2-methylpropoxy)ethoxy]ethyl}benzene-1,4-diamine	7.717	1.96	1.819
15	aniline	58.446	0.679	1.758
16	1-{1-[2-(ethyl{4-[phenyldiazenyl]phenyl}amino)ethoxy]ethoxy}-2-methylpropan-2-ol	1.595	1.147	2.27
17	4-[phenyldiazenyl]aniline	4.144	1.373	1.167
18	[1-(2-methylpropoxy)ethoxy]acetic acid	14770.233	7560.438	3667.925
19	benzene-1,4-diamine	713.566	0.815	4.562

 

ID	IUPAC	BIOWIN v4.10	BCFBAF v3.01. Arnot-Gobas BCF Methods (including biotransformation rate estimates)
		Ready Biodegradability Prediction	Log BCF	BCF L/kg wet-wt
2	N-{2-[1-(2-methylpropoxy)ethoxy]ethyl}-4-[phenyldiazenyl]aniline	NO	(upper trophic) = 2.751 (mid trophic) = 2.865 (lower trophic) = 2.896	(upper trophic) = 563.3 (mid trophic) = 733.1 (lower trophic) = 787.4
3	acetaldehyde	YES	(upper trophic) = -0.033 (mid trophic) = -0.019 (lower trophic) = -0.016	(upper trophic) = 0.9265 (mid trophic) = 0.9573 (lower trophic) = 0.9636
4	N-ethyl-4-[phenyldiazenyl]aniline	NO	(upper trophic) = 2.615 (mid trophic) = 2.654 (lower trophic) = 2.654	(upper trophic) = 412.1 (mid trophic) = 450.5 (lower trophic) = 451.2
5	[1-(2-methylpropoxy)ethoxy]acetaldehyde	YES	(upper trophic) = 0.087 (mid trophic) = 0.071 (lower trophic) = 0.065	(upper trophic) = 1.221 (mid trophic) = 1.177 (lower trophic) = 1.161
6	1-(2-methylpropoxy)ethan-1-ol	NO	(upper trophic) = 0.026 (mid trophic) = 0.029 (lower trophic) = 0.028	(upper trophic) = 1.061 (mid trophic) = 1.069 (lower trophic) = 1.066
7	(ethyl{4-[phenyldiazenyl]phenyl}amino)acetaldehyde	NO	(upper trophic) = 2.152 (mid trophic) = 2.193 (lower trophic) = 2.195	(upper trophic) = 142 (mid trophic) = 156.1 (lower trophic) = 156.7
8	2-(ethyl{4-[phenyldiazenyl]phenyl}amino)ethan-1-ol	NO	(upper trophic) = 1.925 (mid trophic) = 2.006 (lower trophic) = 2.023	(upper trophic) = 84.15 (mid trophic) = 101.3 (lower trophic) = 105.4
9	2-methylpropyl acetate	YES	(upper trophic) = 0.581 (mid trophic) = 0.553 (lower trophic) = 0.535	(upper trophic) = 3.809 (mid trophic) = 3.57 (lower trophic) = 3.431
10	2-methylpropan-1-ol	YES	(upper trophic) = 0.120 (mid trophic) = 0.099 (lower trophic) = 0.092	(upper trophic) = 1.317 (mid trophic) = 1.257 (lower trophic) = 1.235
11	2-(ethyl{4-[phenyldiazenyl]phenyl}amino)ethyl acetate	NO	(upper trophic) = 1.729 (mid trophic) = 1.862 (lower trophic) = 1.902	(upper trophic) = 53.61 (mid trophic) = 72.76 (lower trophic) = 79.79
12	1-[2-(ethyl{4-[phenyldiazenyl]phenyl}amino)ethoxy]ethan-1-ol	NO	(upper trophic) = 1.710 (mid trophic) = 1.772 (lower trophic) = 1.782	(upper trophic) = 51.28 (mid trophic) = 59.22 (lower trophic) = 60.56
13	2-methylpropanal	YES	(upper trophic) = 0.137 (mid trophic) = 0.105 (lower trophic) = 0.095	(upper trophic) = 1.372 (mid trophic) = 1.273 (lower trophic) = 1.245
14	N1-ethyl-N1-{2-[1-(2-methylpropoxy)ethoxy]ethyl}benzene-1,4-diamine	NO	(upper trophic) = 1.393 (mid trophic) = 1.437 (lower trophic) = 1.440	(upper trophic) = 24.74 (mid trophic) = 27.34 (lower trophic) = 27.52
15	aniline	NO	(upper trophic) = 0.211 (mid trophic) = 0.158 (lower trophic) = 0.142	(upper trophic) = 1.624 (mid trophic) = 1.437 (lower trophic) = 1.388
16	1-{1-[2-(ethyl{4-[phenyldiazenyl]phenyl}amino)ethoxy]ethoxy}-2-methylpropan-2-ol	NO	(upper trophic) = 2.182 (mid trophic) = 2.301 (lower trophic) = 2.334	(upper trophic) = 152.1 (mid trophic) = 199.9 (lower trophic) = 215.8
17	4-[phenyldiazenyl]aniline	NO	(upper trophic) = 2.047 (mid trophic) = 2.021 (lower trophic) = 2.001	(upper trophic) = 111.5 (mid trophic) = 104.9 (lower trophic) = 100.2
18	[1-(2-methylpropoxy)ethoxy]acetic acid	NO	(upper trophic) = 0.185 (mid trophic) = 0.144 (lower trophic) = 0.131	(upper trophic) = 1.533 (mid trophic) = 1.392 (lower trophic) = 1.351
19	benzene-1,4-diamine	NO	(upper trophic) = -0.040 (mid trophic) = -0.022 (lower trophic) = -0.018	(upper trophic) = 0.9124 (mid trophic) = 0.9503 (lower trophic) = 0.9583

 

ID	IUPAC	Review
		P / VP ?	B / VB?	T?	Overall
2	N-{2-[1-(2-methylpropoxy)ethoxy]ethyl}-4-[phenyldiazenyl]aniline	Y	N	Y	Not PBT / vP/VB
3	acetaldehyde	N	N	Y	Not PBT / vP/VB
4	N-ethyl-4-[phenyldiazenyl]aniline	Y	N	Y	Not PBT / vP/VB
5	[1-(2-methylpropoxy)ethoxy]acetaldehyde	N	N	Y	Not PBT / vP/VB
6	1-(2-methylpropoxy)ethan-1-ol	Y	N	N	Not PBT / vP/VB
7	(ethyl{4-[phenyldiazenyl]phenyl}amino)acetaldehyde	Y	N	Y	Not PBT / vP/VB
8	2-(ethyl{4-[phenyldiazenyl]phenyl}amino)ethan-1-ol	Y	N	Y	Not PBT / vP/VB
9	2-methylpropyl acetate	Y	N	N	Not PBT / vP/VB
10	2-methylpropan-1-ol	N	N	N	Not PBT / vP/VB
11	2-(ethyl{4-[phenyldiazenyl]phenyl}amino)ethyl acetate	Y	N	Y	Not PBT / vP/VB
12	1-[2-(ethyl{4-[phenyldiazenyl]phenyl}amino)ethoxy]ethan-1-ol	Y	N	Y	Not PBT / vP/VB
13	2-methylpropanal	N	N	N	Not PBT / vP/VB
14	N1-ethyl-N1-{2-[1-(2-methylpropoxy)ethoxy]ethyl}benzene-1,4-diamine	Y	N	Y	Not PBT / vP/VB
15	aniline	Y	N	Y	Not PBT / vP/VB
16	1-{1-[2-(ethyl{4-[phenyldiazenyl]phenyl}amino)ethoxy]ethoxy}-2-methylpropan-2-ol	Y	N	Y	Not PBT / vP/VB
17	4-[phenyldiazenyl]aniline	Y	N	Y	Not PBT / vP/VB
18	[1-(2-methylpropoxy)ethoxy]acetic acid	Y	N	N	Not PBT / vP/VB
19	benzene-1,4-diamine	Y	N	N	Not PBT / vP/VB

 

Applicant's summary and conclusion

Conclusions:

The main identified biodegradation products predicted by PPS identified 18 potential biodegradation products. These were subsequently assessed using QSAR for the following parameters:
• Carcinogenicity
• Reproductive toxicity.
• Biodegradation.
• Bioaccumulation
• Toxicity to aquatic organisms.
The results of these assessments where then utilised to derive a screening assessment of all degradants in terms of PBT and vPvB potential characteristics. The outcome of the assessment is that whilst certain characteristics show potential hazards, no potential degradant is considered to be PBT and vPvB overall. There is therefore considered to be no significant hazard associated with the degradants of Solvent Yellow 124.

Executive summary:

The main identified biodegradation products predicted by PPS identified 18 potential biodegradation products. These were subsequently assessed using QSAR for the following parameters:

·       Carcinogenicity

·       Reproductive toxicity.

·       Biodegradation.

·       Bioaccumulation

·       Toxicity to aquatic organisms.

The results of these assessments where then utilised to derive a screening assessment of all degradants in terms of PBT and vPvB potential characteristics. The outcome of the assessment is that whilst certain characteristics show potential hazards, no potential degradant is considered to be PBT and vPvB overall. There is therefore considered to be no significant hazard associated with the degradants of Solvent Yellow 124.