Sodium phenylacetate

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Endpoint:

biodegradation in water: screening tests

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

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 limited documentation / justification

Justification for type of information:

The supporting QMRF report has been attached.

Qualifier:

according to guideline

Guideline:

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

Principles of method if other than guideline:

Prediction was done using OECD QSAR tool box v.3.3

GLP compliance:

not specified

Specific details on test material used for the study:

- Name( IUPAC): sodium 2-phenylacetate
- Name of test material (as cited in study report): Sodium phenylacetate
- Molecular formula C8H8O2.Na
- Molecular weight: 158.1313 g/mol
- Smiles notation : c1(ccccc1)CC(=O)[O-].[Na+]
- InChl: 1S/C8H8O2.Na/c9-8(10)6-7-4-2-1-3-5-7;/h1-5H,6H2,(H,9,10);/q;+1/p-1
- Substance type: Organic
- Physical state: Liquid

Oxygen conditions:

aerobic

Inoculum or test system:

other: Microorganisms

Duration of test (contact time):

28 d

Parameter followed for biodegradation estimation:

other: BOD

Key result

Parameter:

other: BOD

Value:

1

Sampling time:

28 d

Remarks on result:

other: other details are not available

Details on results:

The test chemical sodium 2-phenylacetate showed only 1 % biodegradation by considering BOD as parameter in 28 days.

The prediction was based on dataset comprised from the following descriptors: BOD
Estimation method: Takes average value from the 5 nearest neighbours
Domain  logical expression:Result: In Domain

(((((("a" or "b" or "c" or "d" )  and "e" )  and "f" )  and "g" )  and ("h" and ( not "i") )  )  and ("j" and "k" )  )

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as Aryl OR Carboxylic acid by Organic Functional groups ONLY

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as Aryl AND Carboxylic acid by Organic Functional groups (nested)

Domain logical expression index: "c"

Referential boundary: The target chemical should be classified as Aliphatic Carbon [CH] AND Aliphatic Carbon [-CH2-] AND Aromatic Carbon [C] AND Carbonyl, aliphatic attach [-C(=O)-] AND Miscellaneous sulfide (=S) or oxide (=O) AND Olefinic carbon [=CH- or =C<] by Organic functional groups (US EPA)

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as Anion AND Aromatic compound AND Carbonic acid derivative AND Carboxylic acid derivative AND Carboxylic acid salt AND Cation by Organic functional groups, Norbert Haider (checkmol)

Domain logical expression index: "e"

Referential boundary: The target chemical should be classified as days - weeks by Biodeg primary (Biowin 4) ONLY

Domain logical expression index: "f"

Referential boundary: The target chemical should be classified as Does NOT Biodegrade Fast by Biodeg probability (Biowin 5) ONLY

Domain logical expression index: "g"

Referential boundary: The target chemical should be classified as Bioavailable by Lipinski Rule Oasis ONLY

Domain logical expression index: "h"

Referential boundary: The target chemical should be classified as Group 1 - Alkali Earth Li,Na,K,Rb,Cs,Fr AND Group 14 - Carbon C AND Group 16 - Oxygen O by Chemical elements

Domain logical expression index: "i"

Referential boundary: The target chemical should be classified as Group 15 - Nitrogen N OR Group 15 - Phosphorus P OR Group 16 - Sulfur S OR Group 17 - Halogens Br OR Group 17 - Halogens Cl OR Group 17 - Halogens F,Cl,Br,I,At OR Group 2 - Alkaline Earth Be,Mg,Ca,Sr,Ba,Ra by Chemical elements

Domain logical expression index: "j"

Parametric boundary:The target chemical should have a value of Molecular weight which is >= 146 Da

Domain logical expression index: "k"

Parametric boundary:The target chemical should have a value of Molecular weight which is <= 228 Da

Validity criteria fulfilled:

not specified

Interpretation of results:

not readily biodegradable

Conclusions:

The test chemical sodium 2-phenylacetate showed 1 % biodegradation by considering BOD as a parameter and microorganism as a inoculum in 28 days. By this value of percent biodegradability this chemical sodium 2- phenylacetate is considered as not readily biodegradable.

Executive summary:

Biodegradbility of test chemical sodium 2-phenylacetate (CAS no. 114 -70 -5) is predicted using OECD QSAR tool box v.3.3 using log Kow as primary descriptor. The test chemical sodium 2-phenylacetate showed 1% biodegradation by considering BOD as a parameter and microorganism as a inoculumin 28 days. By this value of percent biodegradability this chemical sodium 2- phenylacetate is considered as not readily biodegradable.

Description of key information

Biodegradbility of test chemical sodium 2-phenylacetate ( CAS no. 114 -70 -5) is predicted using OECD QSAR tool box v.3.3 using log Kow as primary descriptor. The test chemical sodium 2-phenylacetate showed 1 % biodegradation by considering BOD as a parameter and microorganism as a inoculumin 28 days. By this value of percent biodegradability this chemical sodium 2- phenylacetate is considered as not readily biodegradable.

Key value for chemical safety assessment

Biodegradation in water:

under test conditions no biodegradation observed

Additional information

Predicted data for target compound sodium 2-phenylacetate (CAS no. 114 -70 -5) and supporting weight of evidence studies for its closest read across chemicals with log Kow as a primary descriptor were reviewed for the biodegradation endpoint which are summarized as below.

Biodegradability of test chemical sodium 2-phenylacetate (CAS no. 114 -70 -5) is predicted using OECD QSAR tool box v.3.3 using log Kow as primary descriptor. The test chemical sodium 2-phenylacetate showed 1 % biodegradation by considering BOD as a parameter and microorganism as a inoculums in 28 days. By this value of percent biodegradability this chemical sodium 2- phenylacetate is considered as not readily biodegradable.

 

In the Supporting weight of evidence study from authoritative database (J Check, 2017) of read across chemical Sodium 2-(naphthalen-1-yl) acetic acid (CAS no. 86-87-3) biodegradation test was carried out by taking sludge as inoculums at 30 mg/L concentration. Biodegradation was analyzed by BOD, TOC and HPLC parameter. The initial concentration of read across chemical was 100 mg/L and study design is of standard type. After 2 weeks (14 days) test chemical 2-(naphthalen-1-yl) acetic acid showed 0% biodegradation BOD parameter, 5 % biodegradation by TOC parameter and 1 % biodegradation by HPLC parameter in 14 days. So it is concluded that this read across chemical is not readily biodegradable.

 

In another supporting weight of evidence study from same source as mentioned above of read across chemical Benzylbenzene (CAS no. 101-81-5) biodegradation test was carried out by taking sludge as inoculums at 30 mg/L concentration. Biodegradation was analysed by using BOD and GC parameters. The initial concentration of read cross chemical was 100 mg/L and study design is of improved type for a volatile substance. After 2 weeks (14 days) read across chemical showed 0% biodegradation by both BOD and GC parameter so it is concluded that this read across chemical is not readily biodegradable

 

On the basis of above results for target chemical sodium 2-phenylacetate (CAS no. 114 -70 -5) from (OECD QSAR tool box v3.3, 2017) and for its read across substances (from authoritative database J Check) the target chemical sodium 2-phenylacetate can be expected to be not readily biodegradable.